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Year Author Title Journal/Proceedings
2015 Pilat, A.K. Study on electromagnetic force in conical axial magnetic bearing Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: This paper presents two models of a single coil cylindrical electromagnet with a conical shape. The point of interest is focussed on the electromagnetic force, features and limitations of a such models. The calculations were realised with the support of COMSOL Multiphysics software. The 3D models allowed to expand knowledgebase about the electromagnetic force components not visible in the 2D axisymmetry mode.
BibTeX:
@inproceedings{WMLT10_1,
  author = {A. K. Pilat},
  title = {Study on electromagnetic force in conical axial magnetic bearing},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_1.pdf}
}
2015 Rudolph, J. and Werner, R. Untersuchungen an einem streuflussbasierten Messsystem zur Bestimmung der Wellenposition Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: Dieser Beitrag beschreibt das Betriebsverhalten von Magnetfeldsensoren, mit denen die Position der Welle im Magnetlager durch Auswertung der magnetischen Streuflüsse bestimmt werden kann. Es werden Untersuchungen zum thermischen sowie zum frequenzabhängigen Übertragungsverhalten der Sensoren vorgestellt. Weiterhin wird eine Vorrichtung zur Kalibrierung der Sensoren beschrieben und abschließend ein verbessertes Verfahren zur Kompensation der durch Steuerströme verursachten Einflüsse vorgestellt.
BibTeX:
@inproceedings{WMLT10_10,
  author = {J. Rudolph and R. Werner},
  title = {Untersuchungen an einem streuflussbasierten Messsystem zur Bestimmung der Wellenposition},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_10.pdf}
}
2015 Li, L. Experimentelle Untersuchung des Konzeptes adaptiver Zustandsregelung anhand Parameteridentifikation Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: Magnetlager können nicht nur Verschleiß- und Lebensdauerprobleme, sondern auch Rauschprobleme, lösen. Die Störungen auf das System und die Variation der Systemeigenschaften beeinflussen die Funktionalität. Eine Zustandsregelung zeigt Vorteile in der Regelqualität. Die Nichtlinearitäten und die Parameterunsicherheiten der aktiven Magnetlager machen eine optimale Regelung schwer. Die Arbeit präsentiert eine Methode der adaptiven Zustandsregelung mit Nutzung des Softcomputing. Zuerst wird ein Kalmanfilter entwickelt, um Zustandsgrößen erfassen zu können. Danach wird ein Systemmodell auf Basis der Fuzzylogik erstellt. Ziel ist es, die Nichtlinearitäten und Parameterunsicherheiten im Modell zu berücksichtigen. Zuletzt wird eine adaptive Zustandregelung entwickelt, damit wird eine optimale Regelung für jeden aktuellen Arbeitspunkt ermöglicht. Weiterhin werden in einer experimentellen Untersuchung die Vorteile des neuen Konzeptes gegenüber dem traditionellem Zustandsregler nachgewiesen.
BibTeX:
@inproceedings{WMLT10_11,
  author = {L. Li},
  title = {Experimentelle Untersuchung des Konzeptes adaptiver Zustandsregelung anhand Parameteridentifikation},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_11.pdf}
}
2015 Seifert, R., Bahr, F. and Hofmann, W. Modellierung axialer Magnetlager aus Stahl- und SMC-Komponenten mit Wirbelstromeffekten Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: Die elektromagnetische Dynamik von axialen Magnetlagern ist im besonderen Maße von den eingesetzten Materialien abhängig. Axiale Flussverläufe machen eine Blechung von Stator und Rotor unwirksam und hohe induzierte Spannungen rufen im Magnetkreis wirbelstrombedingte Gegenfelder hervor. Zusätzliche kompensierende Magnetisierungsströme lassen den messbaren Strom der Steuerspule dem kraftbildenden Hauptfluss vorauseilen. Steigende Anforderungen an die Regeldynamik erfordern daher den Einsatz schwach elektrisch leitfähiger Kernmaterialien (Soft Magnetic Composites) oder eine Berücksichtigung der auftretenden Wirbelstromeffekte in der Regelstrecke unter Anwendung von Systemen gebrochenrationaler Ordnung. Beide Optionen werden in diesem Beitrag aus analytischer Sicht gegenübergestellt und ihre Anwendungsfälle diskutiert.
BibTeX:
@inproceedings{WMLT10_2,
  author = {R. Seifert and F. Bahr and W. Hofmann},
  title = {Modellierung axialer Magnetlager aus Stahl- und SMC-Komponenten mit Wirbelstromeffekten},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_2.pdf}
}
2015 Pilat, A.K. Study on radial active magnetic bearing for flexible shaft Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: This paper presents the results of selected analysis realised for the flexible shaft with a solid rotor and 8 pole heteropolar active magnetic bearing designed for a such configuration. The calculations were realised with the support of COMSOL Multiphysics software. The 3D models allowed to expand previous analysis with eigenfrequencies and electromagnetic force calculated for a complete bearing as well for deviated rotor (as simulated orientation for flexible mode).
BibTeX:
@inproceedings{WMLT10_3,
  author = {A. K. Pilat},
  title = {Study on radial active magnetic bearing for flexible shaft},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_3.pdf}
}
2015 Düsterhaupt, S. and Worlitz, F. Magnet- und Fanglagerprüfstand MFLP – Versuchsanlage zum Test von Magnet und Fanglagerungen unter extremen Bedingungen Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: Aktive Magnetlagerungen (AMB) stellen eine Schlüsseltechnologie in modernen Turbomaschinen dar. Der Einsatz von AMB in Turbomaschinen der Kraftwerkstechnik (Dampfturbinen, Kühlmittelpumpen und Verdichter) ist durch extreme Prozess- und Umgebungsbedingungen charakterisiert, wie hohe Temperaturen und korrosive Fluide/Gase. Insbesondere der Einsatz organischer Isolationsstoffe begrenzt derzeit den Einsatztemperaturbereich der elektromagnetischen Aktoren. Aktuell sind industrieübliche Isolationssysteme in Spulenwicklungen und Blechpaketen bis 180 °C dauerhaft temperaturstabil. Bekannte Isolationssysteme auf keramischer Basis erlauben Einsatztemperaturen bis zu 450 °C. Die Fertigung ist jedoch aufwendig und das Bauvolumen ist im Gegensatz zu konventionell isolierten Aktoren größer. Fortschritte in der Oberflächentechnik und in den Werkstoffwissenschaften ermöglichen die Entwicklung neuartiger Isolationssysteme. Diese eignen sich aufgrund ihrer Temperaturstabilität für den Einsatz in Hochtemperaturmagnetlagerungen (HTAMB). Beispielsweise erlaubt die Anwendung der PVDBeschichtungstechnologie (Physical Vapor Deposition) die Herstellung kostengünstiger Dünnschichten im einstelligen Mikrometerbereich. Weiterhin ist es ein erklärtes Ziel, Magnet- und Fanglagerungen (CB) in einer Baueinheit unterzubringen. Dies ermöglicht kompakte Maschinendesigns. Es ist geplant, diese Lagereinheiten nahe am oder direkt im Prozessraum unterzubringen. So müssen auch die Fanglagerungen ihre Funktionen unter extremen Umgebungsbedingungen zu erfüllen.
BibTeX:
@inproceedings{WMLT10_4,
  author = {S. Düsterhaupt and F. Worlitz},
  title = {Magnet- und Fanglagerprüfstand MFLP – Versuchsanlage zum Test von Magnet und Fanglagerungen unter extremen Bedingungen},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_4.pdf}
}
2015 Paditz, M., Nickel, A. and Hübner, N. Anwendungsbeispiele und Erfahrungen beim Einsatz magnetischer Lager Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: Seit mehr als 20 Jahren werden bei EAAT magnetische Lager und magnetgelagerte Antriebe, individuell angepasst an die Kundenanforderungen, entwickelt und gebaut. Zum Einsatz kamen diese Lager in zahlreichen Gebieten z. B. in der Kernforschung, der Medizintechnik, Textiltechnik und in Bearbeitungsmaschinen zum Fräsen und Bohren. Weiterhin finden Magnetlager Anwendung in der Prüftechnik z. B. zur Prüfung von Gleit- und Wälzlagern oder in der Materialprüftechnik. Auch für verschiedene Schwungrad- und Drallradanwendungen wurden bei EAAT schon Magnetlager entwickelt. In diesem Beitrag sollen einige Anwendungsbeispiele für magnetische Lager vorgestellt sowie auf Erkenntnisse und Erfahrungen beim Einsatz solcher Lager eingegangen werden.
BibTeX:
@inproceedings{WMLT10_5,
  author = {M. Paditz and A. Nickel and N. Hübner},
  title = {Anwendungsbeispiele und Erfahrungen beim Einsatz magnetischer Lager},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_5.pdf}
}
2015 Haje, D. Oelfreie Siemens Industriedampfturbine - Erste Betriebserfahrungen Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: Die erste ölfreie Siemens Industriedampfturbine wurde Anfang 2015 erfolgreich in Betrieb genommen und treibt seitdem eine Kesselspeisepumpe an. Dieser Beitrag berichtet über die ausgeführte Technik und erste Betriebserfahrungen.
BibTeX:
@inproceedings{WMLT10_6,
  author = {D. Haje},
  title = {Oelfreie Siemens Industriedampfturbine - Erste Betriebserfahrungen},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_6.pdf}
}
2015 Gouws, J., Rensburg, J.V. and Vanek, C. Backup-Bearing Lifetime Prediction using Quantified Delevitation Severity Indicators Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: In order to improve backup bearing reliability and safety, the applicability of using quantified delevitation severity indicators Dval, Vval (as described in [1]) and AVval for predicting backup bearing life is investigated. Degradation data is gathered using a small-scale experimental test bench to delevitate a rotor under specific initial conditions and simultaneously logging the Dval value for several repeated rotor delevitation events (RDEs). Three individual sets of backup bearing degradation data is shown indicating that delevitation severity indicators change as the bearing degrades. This change could enable condition monitoring of the backup bearings where the ultimate goal of this research is to induce repeatable backup bearing failures, and subsequently analyse the Dval, Vval and AVval data in order to predict future failures on a new set of backup bearings.
BibTeX:
@inproceedings{WMLT10_7,
  author = {J.M. Gouws and J.J. Van Rensburg and C. Vanek},
  title = {Backup-Bearing Lifetime Prediction using Quantified Delevitation Severity Indicators},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_7.pdf}
}
2015 Mitterhofer, H. Lagerloser Hochgeschwindigkeitsantrieb Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: Besonders bei Antrieben von generell kleiner Baugröße ist oft höchste Kompaktheit gefordert. Geht es dabei zusätzlich um ein magnetisch gelagertes System, so können lagerlose Motoren, die die magnetische Lagerung physisch mit dem elektrischen Motor vereinen, besonders interessant werden. Setzt die Anwendung außerdem auf einen scheibenförmigen Rotor, so kann aufgrund der magnetisch passiven Stabilisierung der axialen und Kippfreiheitsgrade (siehe Abbildung 2) ein Maximum an topologischer Kompaktheit realisiert werden.
BibTeX:
@inproceedings{WMLT10_8,
  author = {H. Mitterhofer},
  title = {Lagerloser Hochgeschwindigkeitsantrieb},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_8.pdf}
}
2015 Hoffmann, L. Wirbelstrommessketten speziell für Magnetlager Proceedings of Workshop on Magnetic Bearing Technology 10  
Abstract: Die Anwendung von Magnetlagern sind vielfältig, so werden diese unter anderem im Werkzeugmaschinenbau eingesetzt. Anwendungsbeispiele sind dabei Fräsen, Schleifen, Bohren, Zentrifugen und Pumpen. Weiterhin eignen sich Magnetlager auch für Bearbeitungsspindeln für das Polieren von Oberflächen. Um eine sichere Regelung zu realisieren, werden hochauflösende und hochdynamische Messsysteme zur exakten Lagebestimmung eingesetzt. Hierfür werden oftmals Wirbelstrommesssysteme verwendet, da diese unempfindlich gegenüber Staub, Öl und weiteren Umgebungseinflüssen sind. Besondere Vorteile von Wirbelstromsensoren sind deren verhältnismäßig niedrige Preis und die Synchronisierbarkeit bei Wellendurchmessern unter 25 mm. Gegenwärtig werden in der EAAT u.a. Untersuchungen zur Herstellung eigener Wirbelstromsensoren durchgeführt. Hierzu werden neben den geeigneten Materialien für die Sensoren, deren notwendige Induktivität, der Einfluss verschiedener Sensorkopfdurchmesser etc. ermittelt. Grundlegende Schwerpunkte bilden geeignete Speisekabel und das Temperaturdriftverhalten, da Magnetlager auch für höhere Temperaturen einsetzbar sind. Die bevorzugten Baugrößen der Wirbelstromsensoren belaufen sich auf (6 und 8) mm Durchmesser. Das Fanglagerspiel und der kleinste Wellendurchmesser bestimmten dabei diese Baugrößen. Um Untersuchungen der Sensoren durchführen zu können, bedarf es einer geeigneten Auswerteelektronik. Die Anforderungen an diese Elektronik liegt in deren Universalität, d.h. es sollen nach Möglichkeit nicht nur eigens hergestellte Sensoren angeschlossen werden können, sondern ebenso auch Sensoren von Fremdherstellern. Dabei wird eine kostengünstige Auswerteelektronik angestrebt, welche zwischen Spannungs- und Stromcharakteristik umschaltbar ist. Bei Bedarf ist eine Linearisierung der Wirbelstrommesssignale möglich. Im Beitrag wird die Low-Cost Auswerteelektronik mit verschiedenen Linearisierungsvorschlägen der Sensorsignale als auch deren Universalität vorgestellt.
BibTeX:
@inproceedings{WMLT10_9,
  author = {L. Hoffmann},
  title = {Wirbelstrommessketten speziell für Magnetlager},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 10},
  year = {2015},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt10/wmlt10_9.pdf}
}
2014 Zhang, P., Wang, Z. and Xi, G. Novel Permanent-Magnet-Biased Axial Hybrid Magnetic Bearings Without a Thrust Disc Proceedings of ISMB14  
Abstract: The paper proposes a pair of novel permanent-magnet-biased axial hybrid magnetic bearings, which are assembled at ends of a compressor spindle. The outer diameter of rotor is minimized to reduce the wind loss, which is regarded as the main loss in a typical axial magnetic bearing for a compressor. The bias magnetic flux, provided by an axial polarized permanent magnet ring, diminishes the loss further. The paper firstly introduces the structure and the working principle of the new axial hybrid magnetic bearing system. The cooling holes are aimed to improving the cooling capability without degrading the load capacity. Then, the axial magnetic attraction forces of axial magnetic bearings in pairs, under the condition without the cooling holes, are calculated by 2-D Finite Element Method (FEM) and 3-D FEM respectively. Additionally, another 3-D model is set up to investigate the influence of the designed cooling holes on the axial force. The coupling of the magnetic force and the flux density limit of iron cores are analyzed. The numerical results indicate that the proposed structure of the axial magnetic bearing system is feasible.
BibTeX:
@inproceedings{ISMB14_1,
  author = {Pengfei Zhang and Zhiheng Wang and Guang Xi},
  title = {Novel Permanent-Magnet-Biased Axial Hybrid Magnetic Bearings Without a Thrust Disc},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_1.pdf}
}
2014 Garcia, J.D.G., Gomes, A.C.D.N. and Stephan, R.M. Performance Assessment of a Self-Bearing Motor: an Application of ISO 14839 Proceedings of ISMB14  
Abstract: Two different controllers have been applied for the stabilization of a self-bearing motor prototype existing at LASUP/UFRJ (Laboratory of Applied Superconductivity – Federal University of Rio de Janeiro): a PID controller and a LQR controller. This paper compares the performance of those controllers based on criteria described on the ISO 14839 standard, which establishes requirements for AMB (Active Magnetic Bearing) applied to turbo machinery.
BibTeX:
@inproceedings{ISMB14_10,
  author = {Jose Dalvio Ghirello Garcia and Afonso Celso Del Nero Gomes and Richard M. Stephan},
  title = {Performance Assessment of a Self-Bearing Motor: an Application of ISO 14839},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_10.pdf}
}
2014 Karban, P., Mach, F., Kus, P., Korous, L. and Dolezel, I. Code Agros2D and Possibilities of its Use for Modeling and Design of Magnetic Bearings Proceedings of ISMB14  
Abstract: A multi-platform software Agros2D is presented, whose purpose is to model complex 2D multiphysics problems in engineering practice. The code is intended for monolithic solving of systems of generally nonlinear and nonstationary partial differential equations describing particular physical fields. The numerical schemes implemented in the code are based on a fully adaptive higher-order finite element method. The paper discusses the unique features of the code and its internal structure. Its power is demonstrated on an example aimed at modeling of a passive axial magnetic bearing.
BibTeX:
@inproceedings{ISMB14_100,
  author = {Pavel Karban and Frantisek Mach and Pavel Kus and Lukas Korous and Ivo Dolezel},
  title = {Code Agros2D and Possibilities of its Use for Modeling and Design of Magnetic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_100.pdf}
}
2014 Imani-Nejad, M. and Trumper, D. Hysteresis Self-Bearing Motor Proceedings of ISMB14  
Abstract: This paper presents a hysteresis self-bearing motor along with its nonlinear analysis. In this work we introduced a new type of self-bearing motor with segmented stator. The major advantages of this stator are: easy and low cost manufacturing, higher filling factor and shorter magnetic path for the stator. We tested the self-bearing concept successfully with this new configuration. Hysteresis motors are suitable for high speed application since their rotor has neither permanent magnets nor any winding or mechanical features. We used FEA analysis to check the feasibility of proposed idea. Then we used Chua’s hysteresis model to simulate the nonlinear behavior of this system.
BibTeX:
@inproceedings{ISMB14_101,
  author = {Mohammad Imani-Nejad and David Trumper},
  title = {Hysteresis Self-Bearing Motor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_101.pdf}
}
2014 Murakami, M., Masuzawa, T., Onuma, H., Nishimura, T. and Kyo, S. The Thin Maglev Ventricular Assist Device with Radial Type Self-Bearing Motor Proceedings of ISMB14  
Abstract: A small, thin, maglev ventricular assist device, which can be implanted under the thorax muscle layer like a pacemaker, has been developed. A cascade pump, which has inlet and outlet ports in the same plane and a radial type self - bearing motor are adopted to reduce the axial thickness of the device. The radial self - bearing motor is using the passive stability to restrict the impeller movement in the axial direction and its inclination. We evaluated the fluid force acted on the levitated impeller by using the computational fluid dynamics analysis and restoring force and torque by using the magnetic field analysis. Also, an axial hydrodynamic bearing is developed to avoid the impeller contact on the casing when the levitated impeller received a large disturbance. Finally, a prototype pump is developed and evaluated its levitation and pump performance. The prototype pump was levitated and rotated up to a rotating speed of 2,600 rpm successfully. The target performance of a flow rate of 2 L /min against a head pressure of 100 mmHg is achieved with a rotating speed of 2,000 rpm. The maximum oscillation amplitude and the total power consumption with the target performance were 17 µm and 4.5 watts.
BibTeX:
@inproceedings{ISMB14_102,
  author = {Michiko Murakami and Toru Masuzawa and Hiroyuki Onuma and Takashi Nishimura and Syunei Kyo},
  title = {The Thin Maglev Ventricular Assist Device with Radial Type Self-Bearing Motor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_102.pdf}
}
2014 Asama, J., Fujii, Y., Fukuyo, M., Oiwa, T. and Chiba, A. Realization of Magnetic Suspension and Motor Operation with One Three-Phase Voltage Source Inverter Using a Zero-Phase Current Proceedings of ISMB14  
Abstract: This paper focuses on realization of both the single-axis active magnetic suspension and rotation of a three-phase permanent magnet motor using only one three-phase voltage source inverter. The suspension winding of the electromagnet for the single-axis magnetic suspension is connected between the neutral point of the Y-connected three-phase winding and the middle point of the voltage sources, and the resulting zero-phase current is utilized to control the suspension force. The control method of the zero-phase current is theoretically derived to avoid interference with the motor performance. Experimental apparatus was built and tested, which consists of an iron ball magnetic suspension system and a three-phase interior permanent magnet motor. The experimental results demonstrated stable magnetic suspension and motor rotation at 1200 rpm.
BibTeX:
@inproceedings{ISMB14_103,
  author = {Junichi Asama and Yusuke Fujii and Masato Fukuyo and Takaaki Oiwa and Akira Chiba},
  title = {Realization of Magnetic Suspension and Motor Operation with One Three-Phase Voltage Source Inverter Using a Zero-Phase Current},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_103.pdf}
}
2014 Ahn, H.J. and You, Y.H. An Eddy Current Damper for Reaction Force Compensation for a Linear Motor Motion Stage Proceedings of ISMB14  
Abstract: This paper presents an eddy current damper (ECD) for reaction force compensation for a linear motor motion stage. A reaction force compensation mechanism with a movable magnet track and an ECD (or conductor plate) is developed. Lumped model of the ECD is derived considering sinusoidal magnetic flux density distribution and effective width of the ECD. In addition, effects of both the location and width of the conductor plate are discussed. Multi-physical transient analysis of ECD is analyzed using commercial finite element software, which is compared with the lumped parameter analysis. Finally, the derived lumped model is validated with experiments.
BibTeX:
@inproceedings{ISMB14_104,
  author = {Hyeong Joon Ahn and Yo Han You},
  title = {An Eddy Current Damper for Reaction Force Compensation for a Linear Motor Motion Stage},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_104.pdf}
}
2014 Duesterhaupt, S., Neumann, H., Panescu, C., Rottenbach, T. and Worlitz, F. Test Field for Magnetic Bearing Applications Under Extreme Conditions Proceedings of ISMB14  
Abstract: Active magnetic bearings (AMB) are an essential key technology in modern power plant concepts. The application of AMBs in turbo machines (steam turbines, cooling pumps and compressors) is characterized by extreme process and environmental conditions like high temperatures, corrosive fluids and gases. Especially the use of organic materials limits the insulation level of electromagnetic actuators. Currently the allowed maximum continuous temperature of coils and laminated cores is 160C. Known solutions like ceramic insulation systems allow actuator temperatures up to 450C. But their production is complex and the specific actuator size increases compared to conventional insulated actuators. The development of new surface technologies and advances in material science allow new basic approaches for insulations and thereby for High Temperature Active Magnetic Bearings (HTAMBs). For instance the use of the physical vapor deposition technology (PVD) allows low cost coatings with thicknesses of only a few micrometers. Furthermore, the fusion of AMBs with catcher bearings (CB) to an integrated unit is advantageous for a compact machine design. It is one objective to place the bearing units close to the process section, if appropriate into the process section. So the CBs also have to fulfil their functions under extreme conditions.
BibTeX:
@inproceedings{ISMB14_105,
  author = {Stephan Duesterhaupt and Holger Neumann and Christian Panescu and Torsten Rottenbach and Frank Worlitz},
  title = {Test Field for Magnetic Bearing Applications Under Extreme Conditions},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_105.pdf}
}
2014 Tripodi, E., Musolino, A., Rizzo, R. and Casini, D. Stability Analysis of a New Passive PMs Bearing Proceedings of ISMB14  
Abstract: In this paper a new Permanent Magnets (PMs) bearing is presented. The device is composed of a rotor capable to levitate at a short distance from a dedicated stator. The magnetic suspension is achieved by proper configurations of PMs arranged on both the stator and the rotor. The device is characterized by intrinsic instability and passive stabilization is attempted exploiting eddy currents on a conducting sheet surrounding the stator magnets. The system has been simulated by means of a dedicated numerical tool capable to take into account the effects of the magneto-mechanical coupling. In particular, the coupled problem has been integrated by means of a prediction-correction nested scheme. The simulation activity has produced some interesting results, that are here extensively discussed. More specifically, it has been shown that the stability with respect to the center of mass translation can be passively obtained, if the rotations are actively prevented. An idea of an active stabilizing system for the rotations, exploiting the results of the simulation is finally briefly described.
BibTeX:
@inproceedings{ISMB14_106,
  author = {Ernesto Tripodi and Antonino Musolino and Rocco Rizzo and Dante Casini},
  title = {Stability Analysis of a New Passive PMs Bearing},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_106.pdf}
}
2014 Rudolph, J. and Werner, R. Effect of Eddy Currents on the Stray Flux Based Measurement System for Magnetic Bearing Proceedings of ISMB14  
Abstract: This paper concerns the behaviour and special characteristics of an alternative measurement system for magnetic bearing based on stray flux which depends on the rotor position. The impact of eddy currents on the dynamic properties will be analysed and methods for compensation will be presented. Furthermore the effect of electromagnetic disturbance will be a matter and how it can be reduced by special sensor design.
BibTeX:
@inproceedings{ISMB14_107,
  author = {Johannes Rudolph and Ralf Werner},
  title = {Effect of Eddy Currents on the Stray Flux Based Measurement System for Magnetic Bearing},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_107.pdf}
}
2014 Li, L., Kästner, W. and Worlitz, F. Adaptive Kalman Filter for Active Magnetic Bearings Using softcomputing Proceedings of ISMB14  
Abstract: Magnetic bearings can not only solve the bearing wear and life problems but also reduce the loss and noise of bearing. However, the strong disturbance and noise from the system affects the control behavior. Based on the Kalman filter the influence of noise will be reduced. But the strong nonlinear and uncertainty of parameter of the magnetic bearings make it difficult to establish the estimation / prediction equation in Kalman filter. This paper presents a design method of system estimation / prediction for Kalman filter with using soft computing. Firstly, linear local model for axial magnetic bearing overall system will be deduced. Then a few system parameters, which is relative with nonlinear and uncertainty, will be obtained by a intelligence function, which uses soft computing algorithm as system identification. Finally, the identified system parameters will be used in state equation in Kalman filter. It aims at better filter performance and state estimation than the conventional linear Kalman filter.
BibTeX:
@inproceedings{ISMB14_108,
  author = {Li Li and Wolfgang Kästner and Frank Worlitz},
  title = {Adaptive Kalman Filter for Active Magnetic Bearings Using softcomputing},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_108.pdf}
}
2014 Fohler, A. and Zulehner, W. Nitsche-Type Mortaring for Simulation of Electrical Machines Proceedings of ISMB14  
Abstract: We will present a finite element program implementing the idea of Nitsche-type mortaring in the framework of simulating electrical machines. Using this method it is possible to split the domain into subdomains only connected via a function on the interface. From this approach we gain the advantage that adjacent meshes (e.g. rotor and air gap) do not have to fit together nodewise. The mortaring will be used on the interface between rotor and air gap as well as on the symmetry edges of the motor, since only a part of the machine is considered in the simulation due to motor symmetry.
BibTeX:
@inproceedings{ISMB14_109,
  author = {Armin Fohler and Walter Zulehner},
  title = {Nitsche-Type Mortaring for Simulation of Electrical Machines},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_109.pdf}
}
2014 Sun, Z., Zhao, J. and Shi, Z. Identification of Magnetic Bearing System Using a Novel Subspace Identification Method Proceedings of ISMB14  
Abstract: Active magnetic bearings (AMBs) are widely applied to support high-speed rotating machineries, especially in special environment. Identification is a useful method to obtain the mathematical model of an AMB system. Frequency domain subspace identification method (FDSIM) is an attractive identification technique. However, in practice one usually expects that the identified model possesses some properties, for example stability. FDSIM cannot ensure these expected properties. This paper firstly proposes a novel subspace identification method, FDSIM-lamda. This method can guarantee that the resultant model possesses predefined poles. Moreover, an optimization procedure is introduced to obtain the optimal poles based on FDSIM-lamda, the initial estimation of system poles and constraints on the system poles. The proposed method is then applied to identify an AMB system and validated by the experiments on a real AMB system.
BibTeX:
@inproceedings{ISMB14_11,
  author = {Zhe Sun and Jingjing Zhao and Zhengang Shi},
  title = {Identification of Magnetic Bearing System Using a Novel Subspace Identification Method},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_11.pdf}
}
2014 Masuzawa, T. Magnetically Suspended Motor System for Artificial Hearts and Blood Pumps Proceedings of ISMB14  
Abstract: Magnetic levitation technology, for magnetic bearings and magnetically suspended motors, is a cutting edge technology to produce artificial hearts and higher performance blood pumps. A wider blood gap and eliminating the contacting parts in the device based on the maglev technology provide better blood compatibility and higher durability of the device. Novel inventions about the maglev mechanism are required to overcome the size and power limitation of artificial hearts. Specialization of the maglev system is also necessary due to different requirements with the spreading application of artificial hearts. The current research topics of the maglev system for artificial hearts and blood pumps will be presented in the mini-symposium.
BibTeX:
@inproceedings{ISMB14_110,
  author = {Toru Masuzawa},
  title = {Magnetically Suspended Motor System for Artificial Hearts and Blood Pumps},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_110.pdf}
}
2014 Marth, E., Jungmayr, G. and Amrhein, W. Realization of a Multi-Pole Permanent Magnetic Bearing with Rotating Magnetization Proceedings of ISMB14  
Abstract: The optimization of stiffness of a permanent magnetic single ring bearing is presented in this paper. This is achieved by only changing the magnetization pattern. More precisely, a homogeneous magnetization is replaced by a rotating magnetization with two magnetic poles, leading to a 3.7-fold improvement in stiffness. Usually, such a rotating magnetization is realized by stacking several homogeneously magnetized rings with different magnetization direction, which is referred to as Halbach stacking. Our approach was to realize a continuously rotating magnetization pattern in one ring. In order to achieve the maximum possible stiffness for the given bearing dimensions, the optimization of the magnetization process is crucial and also presented in the paper.
BibTeX:
@inproceedings{ISMB14_111,
  author = {Edmund Marth and Gerald Jungmayr and Wolfgang Amrhein},
  title = {Realization of a Multi-Pole Permanent Magnetic Bearing with Rotating Magnetization},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_111.pdf}
}
2014 Kurita, N., Timms, D., Greatrex, N., Kleinheyer, M. and Masuzawa, T. Optimization Design of Magnetically Suspended System for the BiVACOR Total Artificial Heart Proceedings of ISMB14  
Abstract: The BiVACORdevice is a third generation rotary total artificial heart under development to treat end stage cardiovascular disease. Non-contact suspension and rotation of the impeller of the blood pump was achieved by a combination of a permanent magnet hybrid type magnetic bearing and an axial flux brush-less DC motor. Moreover, according to a series of animal trials, functionality of the proposed magnetic system in the total artificial heart application was clarified.
BibTeX:
@inproceedings{ISMB14_112,
  author = {Nobuyuki Kurita and Daniel Timms and Nicholas Greatrex and Matthias Kleinheyer and Toru Masuzawa},
  title = {Optimization Design of Magnetically Suspended System for the BiVACOR Total Artificial Heart},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_112.pdf}
}
2014 Schneider, M., Schaede, H. and Rinderknecht, S. Multicriteria Design Process for Outer-Rotor Kinetic Energy Storage Systems Proceedings of ISMB14  
Abstract: Due to the global energy transition, energy storage capacities are necessary. Kinetic energy storage systems can be used to provide valuable grid services but have to be redesigned to fulfill this task. A structured process is necessary in order to cope with the complexity of those systems and to maximize performance and profitability. This multicriteria design process is described in detail for an outer-rotor kinetic energy storage system. The approach is based on a detailed system model consisting of the several sub-models. It incorporates the design of the drive system, the magnetic bearing system, as well as the composite rotor. This approach enables the use of optimization algorithms in order to find systems matching the application specific objectives such as minimal operational losses or a maximal energy density. The multicriteria design process is then applied to an exemplary application.
BibTeX:
@inproceedings{ISMB14_113,
  author = {Maximilian Schneider and Hendrik Schaede and Stephan Rinderknecht},
  title = {Multicriteria Design Process for Outer-Rotor Kinetic Energy Storage Systems},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_113.pdf}
}
2014 Mitterhofer, H. and Rakov, M. On the Direct Use of Electromagnetic Field Information for Rotor Position Control Proceedings of ISMB14  
Abstract: This article describes a simple principle for obtaining information about the radial rotor position and later on shows how this information can be used to stabilize the rotor deflection in a magnetically levitated system. It is important to notice that the considered demonstration system was designed in a way the discussed effects are clearly noticeable. It is not meant to be a design proposal for an actual motor.
BibTeX:
@inproceedings{ISMB14_114,
  author = {Hubert Mitterhofer and Mikhail Rakov},
  title = {On the Direct Use of Electromagnetic Field Information for Rotor Position Control},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_114.pdf}
}
2014 Hinterdorfer, T., Schulz, A., Sima, H., Hartl, S. and Wassermann, J. Compensation of Unbalance Forces of a Switched Reluctance Machine with Combined Current and Fluxlinkage Control Proceedings of ISMB14  
Abstract: The presented work handles the compensation of unbalance forces for a 6/4-Switched Reluctance Machine (SRM), which generate significant radial magnetic forces in an eccentric motor shaft position. When the rotor is operating e.g. in its principal axis of inertia, these forces must be compensated by the bearings. This is of major interest for long term storage Flyweels where bearing efficiency is a key factor for the overall system performance. Due to the back electromotive force (BEMF) in high speed operation, precise current control is a major challenge. Hence a combination of current and fluxlinkage control is used to minimize the generated radial forces. It can be used for low and high speed applications. For the observation of fluxlinkage two different methods are described. The functionallity is shown by means of simulations and measurement.
BibTeX:
@inproceedings{ISMB14_115,
  author = {Thomas Hinterdorfer and Alexander Schulz and Harald Sima and Stefan Hartl and Johann Wassermann},
  title = {Compensation of Unbalance Forces of a Switched Reluctance Machine with Combined Current and Fluxlinkage Control},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_115.pdf}
}
2014 Hinterdorfer, T., Schulz, A., Sima, H., Hartl, S. and Wassermann, J. Topology Optimization of a Flywheel Energy Storage Rotor Using a Genetic Algorithm Proceedings of ISMB14  
Abstract: This paper deals with topology optimization of the rotor of a flywheel energy storage system (FESS). For isotropic materials the constant stress disc (CSD) is the best choice to maximize energy density. Modern FESS are manufactured of fiber reinforced plastics (FRP), due to their high specific strength. Because of the transverse isotropic material description the optimal rotor topology changes. A genetic algorithm (GA) for nonlinear integer problems will be used to find the best rotor structure which can be manufactured within one filament winding process.
BibTeX:
@inproceedings{ISMB14_116,
  author = {Thomas Hinterdorfer and Alexander Schulz and Harald Sima and Stefan Hartl and Johann Wassermann},
  title = {Topology Optimization of a Flywheel Energy Storage Rotor Using a Genetic Algorithm},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_116.pdf}
}
2014 van Rensburg, J.J., Vanek, C. and Worlitz, F. Backup Bearing Modelling for Turbo Machines with High Axial and Radial Loads Proceedings of ISMB14  
Abstract: The use of active magnetic bearings (AMBs) in turbo machines is an active research topic and the implementation in industrial applications is becoming commonplace. This is especially true when investigating the backup bearings (BBs) for high speed rotors with high axial and radial loads. In AMB supported turbo machines there usually are high axial process forces present, and should the axial AMB (AAMB) fail, these forces need to be supported by the axial backup bearings (ABBs). In order to design appropriate BBs the movement of the rotor and the associated forces produced during a rotor delevitation event (RDE) is of critical importance. These forces should be determined using a rotor delevitation model that includes the forces on all the backup bearings and the effect that these forces have on the rotor stability. This paper presents a short overview of various types of ABBs in the literature and the associated models for these BBs. The second part of the paper presents a model for a novel BB currently under construction at the IPM, and how this model is integrated into the rotor delevitation model BBSim [1]. The third part of the paper presents some results obtained using the proposed ABB model. The results investigate the effect that the radial distance where contact occurs and the axial force present on the rotor has on the RDE severity based on the Vval values.
BibTeX:
@inproceedings{ISMB14_117,
  author = {Jan Janse van Rensburg and Christian Vanek and Frank Worlitz},
  title = {Backup Bearing Modelling for Turbo Machines with High Axial and Radial Loads},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_117.pdf}
}
2014 Siebke, P. and Golbach, H. A Novel Rolling Element Back-Up Bearing for a 9t Rotor Application Proceedings of ISMB14  
Abstract: The paper outlines the development of a novel backup bearing unit which complements Siemens’ new magnetic bearings for an electric motor with a 9 t rotor. The back-up bearing utilizes rolling bearing elements. Principles for the rotor supported by the back-up bearings are derived and used to design the novel, so-called “Smiley” design. Dynamic simulations are presented predicting that the system fulfils the requirements. This is proven by comparison with experimental data.
BibTeX:
@inproceedings{ISMB14_118,
  author = {Peter Siebke and Hermann Golbach},
  title = {A Novel Rolling Element Back-Up Bearing for a 9t Rotor Application},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_118.pdf}
}
2014 Jungmayr, G., Berroth, H.-J., Panholzer, M., Marth, E., Amrhein, W., Jeske, F. and Reisinger, M. Design of a Highly Reliable Fan with Magnetic Bearings Proceedings of ISMB14  
Abstract: Long term analysis at ebm-papst St. Georgen GmbH & Co. KG showed that bearing failures are responsible for 90% of compact fan breakdowns. A magnetically levitated impeller has no contact with the stator and therefore the life expectancy can be essentially increased. This paper presents the design of a magnetically levitated fan. To meet the low-cost requirement, passive magnetic bearings (PMBs) are used to stabilize the radial and tilt deflections of the rotor. By applying an optimized viscoelastic support to the stator, sufficient damping is introduced to the passively stabilized degrees of freedom. The optimization of the stiffness and damping is discussed and the design of the key components, namely the PMB, the active magnetic bearing (AMB) and the passive damping device, is described. Finally the built prototype and measurements are presented.
BibTeX:
@inproceedings{ISMB14_119,
  author = {Gerald Jungmayr and Hans-Jörg Berroth and Martin Panholzer and Edmund Marth and Wolfgang Amrhein and Frank Jeske and Martin Reisinger},
  title = {Design of a Highly Reliable Fan with Magnetic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_119.pdf}
}
2014 Tachibana, K. and Oka, K. Study on Bearingless Motor with Rectified Circuit Coil Proceedings of ISMB14  
Abstract: This paper represents the research finding of levitation and rotation control on bearingless motor with rectified circuit coil. Rectified circuit coil is functioned as transmitting and receiving coil of wireless electric power transmission, and supplies direct current to rotor coils. Rotor coils are used as rotor magnets not using permanent magnets. Even if magnetic force of magnet is strong, normal force will not be generated if magnets are horizontally configured on straight line. So as to generate vertical axial force, the tip form of rotor and stator is made to incline and levitation force (vertical axial force) is acquired using this inclination.
BibTeX:
@inproceedings{ISMB14_12,
  author = {Kunihiko Tachibana and Koichi Oka},
  title = {Study on Bearingless Motor with Rectified Circuit Coil},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_12.pdf}
}
2014 Schmied, J. Rotordynamic Simulations with MADYN 2000 Proceedings of ISMB14  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB14_120,
  author = {Joachim Schmied},
  title = {Rotordynamic Simulations with MADYN 2000},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_120.pdf}
}
2014 Bauer, W., Freudenthaler, P. and Amrhein, W. Experimental Characterization of a Bearingless Rotating Field Axial-Force/Torque Motor Proceedings of ISMB14  
Abstract: The Bearingless Axial-Force/Torque Motor is an air-core coil motor, that can generate axial forces and drive torques concurrently using a common stator winding system. The radial suspension and the tilting stabilization of the bearingless drive is realized by passive repulsive permanent magnetic ring bearings. The end-windings of the concentric, non-overlapping stator coils create axial directed levitation forces, provided that a non-vanishing common-mode current component is present. In contrast to the existing alternating field motor topology, the proposed redesign features a rotating field motor structure for constant, rotor-angle independent drive torque generation. The current investigation concentrates on the verification of the drive parameters via simple and robust measurements. A presentation of the functional prototype concludes the article.
BibTeX:
@inproceedings{ISMB14_121,
  author = {Walter Bauer and Paul Freudenthaler and Wolfgang Amrhein},
  title = {Experimental Characterization of a Bearingless Rotating Field Axial-Force/Torque Motor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_121.pdf}
}
2014 Silber, S., Koppelstätter, W., Weidenholzer, G. and Bramerdorfer, G. MagOpt - Optimization Tool for Mechatronic Components Proceedings of ISMB14  
Abstract: MagOpt is a modular software tool for the simulation and optimization of mechatronic components. It features a flexible structure for the storage of complex data and an open and modular interface to existing third party programs like CAD systems, finite element programs and other simulation software. Parametric design optimization can be carried out with various different optimization strategies like gradient-based methods or multi-objective evolutionary or genetic algorithms.
BibTeX:
@inproceedings{ISMB14_122,
  author = {Siegfried Silber and Werner Koppelstätter and Günther Weidenholzer and Gerd Bramerdorfer},
  title = {MagOpt - Optimization Tool for Mechatronic Components},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_122.pdf}
}
2014 Grund, C. and Haje, D. Qualification of Magnetic Bearings for Industrial Turbines Proceedings of ISMB14  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB14_123,
  author = {Christoph Grund and Detlef Haje},
  title = {Qualification of Magnetic Bearings for Industrial Turbines},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_123.pdf}
}
2014 Gruber, W., Bauer, W. and Radman, K. Comparison of Homopolar and Heteropolar Bearingless Reluctance Slice Motor Prototypes Proceedings of ISMB14  
Abstract: This paper focuses on the operational behavior of two bearingless reluctance slice motor prototypes. After a brief introduction of the two systems, experiences, obtained from both novel bearingless drives, are presented. On this basis, communalities and differences, in various areas, e. g. construction, geometric constraints, winding systems, force to torque ratio, power electronic utilization and efficiency, will be outlined. This will help to point out the applicability of the reluctance slice motor concepts for industrial utilization.
BibTeX:
@inproceedings{ISMB14_124,
  author = {Wolfgang Gruber and Walter Bauer and Karlo Radman},
  title = {Comparison of Homopolar and Heteropolar Bearingless Reluctance Slice Motor Prototypes},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_124.pdf}
}
2014 Radman, K., Bulic, N. and Gruber, W. Loss Analysis of a Bearingless Flux-Switching Slice Motor Proceedings of ISMB14  
Abstract: The bearingless flux-switching slice motor is a recently developed motor concept combining the magnetic rotor suspension of a bearingless slice drive and the topology of a flux-switching drive. In comparison to state of the art bearingless slice motors this concept introduces a magnet free rotor and relatively high torque generation. This offers advantages in industrial and medical applications which require regular rotor replacements and high temperature working conditions. This work will describe the working principles, prototype design, implemented control theory and measurement to determine the losses and evaluate the efficiency.
BibTeX:
@inproceedings{ISMB14_125,
  author = {Karlo Radman and Neven Bulic and Wolfgang Gruber},
  title = {Loss Analysis of a Bearingless Flux-Switching Slice Motor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_125.pdf}
}
2014 Schultz, L., de Haas, O., Berger, D., Kühn, L., Berger, A. and Espenhahn, T. Basics of Superconducting Levitation and its Use in the Transport System SupraTrans II Proceedings of ISMB14  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB14_126,
  author = {Ludwig Schultz and Oliver de Haas and Dietmar Berger and Lars Kühn and Anne Berger and Tilo Espenhahn},
  title = {Basics of Superconducting Levitation and its Use in the Transport System SupraTrans II},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_126.pdf}
}
2014 Weickhmann, M., Katter, M. and Schleede, B. Nd-Fe-B Permanent Magnets for Passive and Hybrid Magnetic Bearings with Extended Application Temperature Range Proceedings of ISMB14  
Abstract: Passive magnetic bearings or hybrid passive magnetic bearings are commonly built up with Sm-Co or with Nd-Fe-B magnets. One of the most important item of those magnets is it’s homogeneity in flux density distribution and the precise angularity. A miss-match would cause an undesired displacement. It may therefore be very important to measure these homogeneity’s and angular deviation very precisely. Some application call for a higher temperature, thus a need of higher remanence Br is inevitable and in some cases the temperature coefficient Tk of remanence Br is also of importance. This may be achieved by applying the Grain Boundary Diffusion GBD. In the following paper we will give an overview of the current development to ensure this future demand. A variation of parameter studies will give an overview of the main influencing factors which act on the bearing forces and stiffness.
BibTeX:
@inproceedings{ISMB14_127,
  author = {Michael Weickhmann and Matthias Katter and Bernd Schleede},
  title = {Nd-Fe-B Permanent Magnets for Passive and Hybrid Magnetic Bearings with Extended Application Temperature Range},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_127.pdf}
}
2014 Poltschak, F. Active Reduction of Bearing Forces of Short Stroke Linear Actuators Proceedings of ISMB14  
Abstract: Linear magnetic actuators are used in industry for a wide area of applications. In order to reach high values for the axial thrust force, the mover commonly features a permanent magnet excitation. Thus, in combination with a slotted stator layout, these actuators exhibit a high destabilizing stiffness in the direction perpendicular to the direction of motion which has to be compensated by the linear bearings. This paper introduces a linear short stroke actuator with an integrated active bearing force compensation to minimize the forces acting on the mechanical bearings. The potential and limits of a bearing force compensation is analyzed based on a short stroke linear actuators with an E-shaped stator layout. It is outlined how far bearing forces can be compensated even for simple actuator layouts. Especially for linear drives oscillating with a high speed this compensation can significantly reduce wear and thus improve lifetime and efficiency as well as reduce the size of the mechanical bearings.
BibTeX:
@inproceedings{ISMB14_128,
  author = {Florian Poltschak},
  title = {Active Reduction of Bearing Forces of Short Stroke Linear Actuators},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_128.pdf}
}
2014 de Haas, O. and Kuehn, L. Superconducting Magnetic Bearings for Industrial Applications Proceedings of ISMB14  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB14_129,
  author = {Oliver de Haas and Lars Kuehn},
  title = {Superconducting Magnetic Bearings for Industrial Applications},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_129.pdf}
}
2014 Fohr, F., Volbers, N. and Gerster, J. High Strength Iron-Cobalt Materials for Magnetic Bearings Proceedings of ISMB14  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB14_13,
  author = {Frederik Fohr and Niklas Volbers and Joachim Gerster},
  title = {High Strength Iron-Cobalt Materials for Magnetic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_13.pdf}
}
2014 Lembke, T. Review of Electrodynamic Bearings Proceedings of ISMB14  
Abstract: When Earnshaw stated his theorem in 1839, it did not seem possible to levitate objects in static magnetic fields. 100 years later Braunbeck 1939 was able to show mathematically that levitation is actually possible in unvarying magnetic fields for diamagnetic materials. Today levitating toys based on weakly diamagnetic graphite and permanent magnets are available on the market. Some other materials like superconductors or moving conductors have properties that to a much higher extent resemble those of diamagnets, and these may also levitate in a static magnetic field. Levitating experimental full scale trains based on both of these effects exist today. In this paper the most important technical achievements regarding electrodynamic levitation will be reviewed, dating from 1922 and on, with particular focus on rotating bearings and demonstrated levitating prototypes.
BibTeX:
@inproceedings{ISMB14_130,
  author = {Torbjörn Lembke},
  title = {Review of Electrodynamic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_130.pdf}
}
2014 Allaire, P., Jiang, W., Kailasan, A. and Dimond, T. Magnetic Bearing System for Left Ventricular Assist Artificial Heart Pump - Combined Active and Passive Configuration Proceedings of ISMB14  
Abstract: Magnetic bearings continue to contribute to the development of ventricular assist artificial heart pumps. This paper describes the magnetic suspension for a unique prototype axial flow pump designed for approximately 6 l/min at 100 mm Hg performance with an operating speed of approximately 7,000 rpm. The integrated magnetic suspension design provides a direct non-contact blood flow path through the pump with no obstructions which might create low flow areas and thrombosis (blood clots). The magnetic suspension is a combination of permanent magnets (PMs) and active magnetic bearings (AMBs). There are two radial AMBs which support the four degrees of freedom at the ends of the axial pump impeller and an axial PM thrust bearing. The axial PM bearing supports the direction of the largest fluid force on the impeller. A major objectives of artificial hearts is to have extremely low power consumption. Thus the integrated PM and AMB suspension system has an operating magnetic suspension power of approximately 2 watts. The design, numerical modeling, and testing of the magnetic suspension system to support the fluid loads and the g loads is described in the paper.
BibTeX:
@inproceedings{ISMB14_131,
  author = {Paul Allaire and Wei Jiang and Arunvel Kailasan and Tim Dimond},
  title = {Magnetic Bearing System for Left Ventricular Assist Artificial Heart Pump - Combined Active and Passive Configuration},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_131.pdf}
}
2014 Jiang, K. and Zhu, C. Identification of Stiffness and Damping via SPHS Excitation and Multi-DOF Active Magnetic Bearing-Rotor Model Proceedings of ISMB14  
Abstract: The equivalent stiffness and the equivalent damping are the important and commonly used parameters for representing the support characteristic of the Active Magnetic Bearing(AMB). A method for measuring the equivalent stiffness and the equivalent damping is proposed with parameter identification via the multi-frequency excitation. The parameter identification is based on the multi-degree of freedom(DOF) rotor model, not the single DOF model, which can not be suitably applied to the multi-DOF AMB-rotor system. Additionally, the Schroeder Phased Harmonic Sequences(SPHS) are applied to generate the signal for the multi-frequency excitation. SPHS can achieve the lowest peak value by means of appropriate selection for the relative phasing of each frequency component, so that the possibility of the rotor vibration exceeding clearances of AMB and the magnetic force reaching saturation is minimized. Finally, the experiments indicate that the proposed method can efficiently reduce the peak value for the superimposed multi-frequency excitation and correctly identify the equivalent stiffness and equivalent damping of the AMB-rotor system. Keywords: active magnetic bearing, multi-frequency excitation, Schroeder phased harmonic sequences, equivalent stiffness, equivalent damping
BibTeX:
@inproceedings{ISMB14_132,
  author = {KeJian Jiang and ChangSheng Zhu},
  title = {Identification of Stiffness and Damping via SPHS Excitation and Multi-DOF Active Magnetic Bearing-Rotor Model},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_132.pdf}
}
2014 Jeon, J.-W., Lee, C.-L., Oh, H.-S. and Kim, J.-M. Novel Cylindrical Magnetic Levitation Stage with High Precision Motion Proceedings of ISMB14  
Abstract: This paper proposed novel cylindrical magnetic levitation stage. This stage can move the cylinder to rotations and translations as well as levitations with high precision in vacuum. This advantage is useful to make a nano patterning on the surface of cylindrical specimen by using electron beam lithography. In this paper, a conceptual design and a detailed design of the novel cylindrical magnetic levitation stage are shown. Firstly, mathematical modeling and simulation results are shown and then experimental results are compared after manufactured.
BibTeX:
@inproceedings{ISMB14_14,
  author = {Jeong-Woo Jeon and Chang-Lin Lee and Hyeon-Seok Oh and Jong-Moon Kim},
  title = {Novel Cylindrical Magnetic Levitation Stage with High Precision Motion},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_14.pdf}
}
2014 Rao, J., Hijikata, W. and Shinshi, T. A Permanent Magnet Free Bearingless Motor for Disposable Centrifugal Blood Pump Proceedings of ISMB14  
Abstract: The disadvantages of disposable centrifugal blood pumps (DCBPs) are the high cost of the disposable pump head due to the use of rare earth magnets and the complex-shaped secondary flow channel due to the space allocated for the magnetic coupling. In order to overcome these problems a permanent magnet free bearingless motor for DCBPs with a smooth secondary flow channel has been developed. The radial position and rotational speed of the rotor are actively controlled, and the axial position and tilt angle of the rotor are passively stabilized by a magnetic reluctance force. Results of magnetic field FEM analysis showed that the proposed bearingless motor has an axial stiffness of 3.50 N/mm and a tilt stiffness of 0.87 Nm/rad. In an experiment, the power consumption of the prototype was less than 30 W without load at a rotational speed of 3000 rpm.
BibTeX:
@inproceedings{ISMB14_15,
  author = {Jun Rao and Wataru Hijikata and Tadahiko Shinshi},
  title = {A Permanent Magnet Free Bearingless Motor for Disposable Centrifugal Blood Pump},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_15.pdf}
}
2014 Mizuno, T., Takahashi, K., Ishino, Y. and Takasaki, M. Proposal of AC Magnetic Suspension Using Magnetic Resonant Coupling Proceedings of ISMB14  
Abstract: A novel AC magnetic suspension using magnetic resonant coupling is proposed and studied both theoretically and experimentally. The conventional AC magnetic suspension with energy transfer function has a problem that energy transfer efficiency is very low because it has a gap. In contrast, even if it has a gap, the energy transfer method using magnetic resonant coupling has high efficiency. In this paper, this method is combined with AC magnetic suspension. An experimental apparatus is fabricated for basic study. The floator was successfully suspended without control, and the self-stabilization characteristic is confirmed.
BibTeX:
@inproceedings{ISMB14_16,
  author = {Takeshi Mizuno and Kei Takahashi and Yuji Ishino and Masaya Takasaki},
  title = {Proposal of AC Magnetic Suspension Using Magnetic Resonant Coupling},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_16.pdf}
}
2014 Schaeffel, C., Katzschmann, M., Mohr, H.-U., Gloess, R., Rudolf, C., Mock, C. and Walenda, C. 6D Planar Magnetic Levitation System - Mag6D Proceedings of ISMB14  
Abstract: The paper describes the structure, the performance and a set of model based design steps of a novel 6 DOF planar magnetic drive system with nanometer positioning accuracy. The movable platform of the system is free of any wiring connection and the upper surface is freely accessible.
BibTeX:
@inproceedings{ISMB14_17,
  author = {Christoph Schaeffel and Michael Katzschmann and Hans-Ulrich Mohr and Rainer Gloess and Christian Rudolf and Christopher Mock and Carolin Walenda},
  title = {6D Planar Magnetic Levitation System - Mag6D},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_17.pdf}
}
2014 Hofer, M., Hutterer, M., Nenning, T. and Schrödl, M. Improved Sensorless Control of a Modular Three Phase Radial Active Magnetic Bearing Proceedings of ISMB14  
Abstract: This paper discusses new results and improvements on the sensorless control of a permanent magnet biased three phase radial active magnetic bearing (AMB), which are also known as hybrid magnetic bearings (HMB). Self-sensing methods offer cost potentials because of a more simple bearing system architecture, but show lower performance in accuracy and bandwidth compared to external position sensors. Thus, making selfsensing technologies competitive to systems with position sensors is a broad field of research and as well a goal of this paper. The proposed sensorless method is based on inductance measurement by voltage pulse injection. Applying an oversampling strategy for current slope measurement reduces the noise of the sensorless obtained rotor position significantly. Timing limitations and operational bandwidth can be improved by utilizing alternative voltage pulse sequences. Further, variations of the permanent magnet bias flux of the HMB prototype are investigated to show the influences on the sensorless rotor position detection method and limitations for applications.
BibTeX:
@inproceedings{ISMB14_18,
  author = {Matthias Hofer and Markus Hutterer and Thomas Nenning and Manfred Schrödl},
  title = {Improved Sensorless Control of a Modular Three Phase Radial Active Magnetic Bearing},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_18.pdf}
}
2014 Dumont, C., Kluyskens, V. and Dehez, B. Impact of the Yoke Material on the Performance of Wounded Electrodynamic Bearings Proceedings of ISMB14  
Abstract: This paper concerns null-flux, centering electrodynamic bearings with an internal rotor made of permanent magnets creating a multipole radial magnetic field and with an external airgap wounded conductor attached to a yoke. The inclusion of a ferromagnetic yoke in front of the permanent magnets has the two following effects. On the one hand, it increases the magnetic flux density in the airgap and the magnitude of the centering Lorentz forces between the rotor and the stator of the device. This is positive since the stiffness associated with the centering force of the bearing increases too. On the other hand, it also induces a negative stiffness due to the reluctant force between the yoke and the magnets usually referred to as the unbalanced magnetic force. The goal of this paper is to investigate about the gain in stiffness and performance associated with the presence of a ferromagnetic yoke in multipole electrodynamic bearings. To this purpose, a method is exposed to evaluate the stiffness and stability of the bearing objectively using a root-loci plot. The results are based on a 2-D analytical model of electrodynamic bearings which is briefly presented in the paper. It is shown that in some cases, the magnetic permeability of the yoke has a very low impact on the bearing performance.
BibTeX:
@inproceedings{ISMB14_19,
  author = {Corentin Dumont and Virginie Kluyskens and Bruno Dehez},
  title = {Impact of the Yoke Material on the Performance of Wounded Electrodynamic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_19.pdf}
}
2014 Genta, G. Kinetic Energy Storage: an Ideal Application for Magnetic Bearings Proceedings of ISMB14  
Abstract: Kinetic energy storage systems have a long history, but in the last half a century many studies and projects aimed to make this form of energy storage competitive with other systems were developed. One of the main problems related to flywheel energy storage is linked to the energy dissipations due to aerodynamic and bearing drag: Magnetic bearings, also due to their ability of working in vacuum, are thus intrinsically required for these applications.
BibTeX:
@inproceedings{ISMB14_2,
  author = {Giancarlo Genta},
  title = {Kinetic Energy Storage: an Ideal Application for Magnetic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_2.pdf}
}
2014 Ding, Q., Wu, G., Deng, Z. and Wang, X. Influence of Fault-Tolerant Stator Structure on Performance of Permanent Magnet Bearingless Slice Machines Proceedings of ISMB14  
Abstract: Fault-tolerant capability is a vital requirement for bearingless slice machine which is used in safety critical application field. This paper compares two bearingless slice machines, conventional permanent magnet bearingless slice machine and fault-tolerant permanent magnet bearingless slice machine, from fault-tolerant capability, suspension and drive performance points of view. Due to introduction of fault-tolerant stator structure, a optimization method for reduction of total harmonic distortion(THD) of back-EMF and electromagnetic coupling between different phases is proposed. Then, some relevant performance comparison, such as fault-tolerant performance, suspension performance as well as drive torque performance, is analyzed by finite element analysis. Finally, several design considerations are presented as guideline for design of bearingless slice machines with fault-tolerant stator structure.
BibTeX:
@inproceedings{ISMB14_20,
  author = {Qiang Ding and Guyu Wu and Zhiquan Deng and Xiaolin Wang},
  title = {Influence of Fault-Tolerant Stator Structure on Performance of Permanent Magnet Bearingless Slice Machines},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_20.pdf}
}
2014 Gerami, A., Allaire, P. and Fittro, R. Modeling and Control of Magnetic Bearings with Nonlinear Magnetization Proceedings of ISMB14  
Abstract: In this paper a nonlinear modeling approach is proposed to operate magnetic bearings above the linear range and near the material saturation point. The goal is to get higher load capacity from an existing AMB system by just changing the software. In order to do this, the system should be operated in the nonlinear region of the magnetization curve and therefore should be modeled nonlinearly. Simulation results show approximately twice the force capability. The controller designed using this approach has a much better transient response and domain of attraction.
BibTeX:
@inproceedings{ISMB14_21,
  author = {Ali Gerami and Paul Allaire and Roger Fittro},
  title = {Modeling and Control of Magnetic Bearings with Nonlinear Magnetization},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_21.pdf}
}
2014 Pennander, L.-O. Recent Development of Soft Magnetic Composite Materials and its Application Proceedings of ISMB14  
Abstract: This paper explores recent material development for Soft Magnetic Composites (SMC) which are based on pure iron metal powders combined with inorganic resistive coatings. SMC components are manufactured by compaction in a shaped tool followed by heat-treatment of the component for stress relaxation and to reach optimal magnetic and mechanical performance. The recently developed Somaloy(R) 5P SMC materials are presented and compared to former technology. The unique combination of material properties and manufacturing process is here concluded to enable possibilities to realize compact and efficient high-frequency electromagnets, a technique that can be an interesting opportunity for large volume, cost efficient magnetic bearings and bearingless applications.
BibTeX:
@inproceedings{ISMB14_22,
  author = {Lars-Olov Pennander},
  title = {Recent Development of Soft Magnetic Composite Materials and its Application},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_22.pdf}
}
2014 Lapotre, B., Takorabet, N., Tabar, F.M., Lateb, R. and Silva, J.D. Radial Force Modeling of bearingless Motors Based on, Spectral Analysis of Field Sources Proceedings of ISMB14  
Abstract: This paper proposes a global harmonic analysis of a multiphase bearingless PM-motor topology to determine the radial force by considering normal and tangential field components. This allows establishing the semi-analytical expressions of the radial force considering the location of field origin. The accuracy of the model is verified by full FEM model using a statistic approach. The semi-analytic model allows predicting the force waveforms according t the stator-rotor topology. The analysis of two specific topologies is performed and highlights the origin of force ripples. The fastness of this semi-analytical model makes it suitable to implement in a design optimization process.
BibTeX:
@inproceedings{ISMB14_23,
  author = {Blaise Lapotre and Nourddine Takorabet and Farid Meibody Tabar and Ramdane Lateb and Joaquim Da Silva},
  title = {Radial Force Modeling of bearingless Motors Based on, Spectral Analysis of Field Sources},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_23.pdf}
}
2014 Felscher, P., Baumann, K. and Alber, O. Active Magnetic Bearings As a Tool for Parameter Identification of Journal Bearings Proceedings of ISMB14  
Abstract: In this overview, it is presented how Active Magnetic Bearings (AMBs) can successfully be used for the measurement of equilibrium positions and the identification of stiffness and damping coefficients of journal bearings. Therefore, the theory of force measurements in AMBs by using either a theoretical or an experimentally derived relation is provided. Different operation modes of AMBs are considered, including the operation as a magnetic actuator. The successful parameter identification of journal bearing properties using AMBs is demonstrated by measurements.
BibTeX:
@inproceedings{ISMB14_24,
  author = {Patrick Felscher and Katrin Baumann and Oliver Alber},
  title = {Active Magnetic Bearings As a Tool for Parameter Identification of Journal Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_24.pdf}
}
2014 Zhou, L., Nejad, M.I. and Trumper, D. Magnetically Suspended Reaction Sphere with One-Axis Hysteresis Drive Proceedings of ISMB14  
Abstract: We have designed, built and tested a magnetically suspended reaction sphere with one-axis hysteresis drive (1DMSRS) in the Precision Motion Control Lab at MIT. This project is aiming at two goals: (a) exploring the possible design of a magnetically suspended reaction sphere for small spacecraft’s attitude control; and (b) evaluating the performance of a hysteresis motor for the reaction wheel/sphere application. The 1D-MSRS is a motor with spherical rotor, which is magnetically suspended in all translational directions, and is driven by hysteresis motor about vertical axis. For the suspension of the sphere, single dimensional magnetic levitation in vertical direction and bearingless motor around the rotor are combined. An equivalent circuit model of the hysteresis motor is used to analyze the motor’s dynamic behavior. Good agreements between computed and measured motor performance validates the model, which provides a useful simulation tool for further MSRS modeling and control. Test results of the 1D-MSRS show that a starting torque of 8.15 mNm is achieved at 0.7 A zero-peak excitation current, and with this excitation the sphere can run up to 12,000 rpm synchronously in lab with the existence of air drag.
BibTeX:
@inproceedings{ISMB14_25,
  author = {Lei Zhou and Mohammad Imani Nejad and David Trumper},
  title = {Magnetically Suspended Reaction Sphere with One-Axis Hysteresis Drive},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_25.pdf}
}
2014 Lopes, M., Sotelo, G.G., Rodriguez, E. and Stephan, R.M. Experimental Tests and Simulations to the Design of an Electrodynamic Bearing Proceedings of ISMB14  
Abstract: This paper describes an electrodynamic suspension system built with permanent magnets and aluminum plates. Initially, a simple case was studied to demonstrate the behavior of the levitation and drag forces for different conditions, such as air gap, angular velocity and thickness of the aluminum target. In the second part, numerical and experimental tests were performed to design an homopolar electrodynamic bearing (EDB). Forces obtained with eccentric operation as well as different rotor radial velocities are presented.
BibTeX:
@inproceedings{ISMB14_26,
  author = {Marcelo Lopes and Guilherme G. Sotelo and Elkin Rodriguez and Richard M. Stephan},
  title = {Experimental Tests and Simulations to the Design of an Electrodynamic Bearing},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_26.pdf}
}
2014 Filatov, A. and Hawkins, L. Comparative Study of Axial/Radial Magnetic Bearing Arrangements for Turbocompressor Applications Proceedings of ISMB14  
Abstract: This article presents results of a comparative study of different radial/axial actuator solutions for an Active Magnetic Bearing (AMB) system in a real-life turbocompressor application.
BibTeX:
@inproceedings{ISMB14_27,
  author = {Alexei Filatov and Larry Hawkins},
  title = {Comparative Study of Axial/Radial Magnetic Bearing Arrangements for Turbocompressor Applications},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_27.pdf}
}
2014 Yang, G., Shi, Z., Liu, X. and Zhao, J. Research and Experiment of Auxiliary Bearings with No Lubrication for Helium Blower of HTR-10 Proceedings of ISMB14  
Abstract: The auxiliary bearing is one of the important parts for the active magnetic bearing (AMB). A new auxiliary bearing design with no lubrication is proposed in this paper. This auxiliary bearing is composed of angular contact ceramic ball bearing. Two pairs of bearing will be distributed on both ends of the rotor. Each pair of bearing arrangement is face to face. Oil or grease will not be applied in this auxiliary bearing. But dry lubrication with MoS2 will be used in this bearing. This auxiliary bearing will be applied in the helium blower of 10MW high-temperature gas-cooled reactor (HTR-10). Oil or grease can’t be used in the primary loop of the HTR-10. The auxiliary bearing is used to support the blower rotor when the AMB fails to work. It must support the dropping rotor and bear the great impact force and friction heat. It is difficult to analyze the falling course of the rotor. There are two difficult problems to solve for the design of auxiliary bearing, including great impact force and friction heat. The preliminary analysis of the rotor was done. The impact force of the auxiliary bearing was computed for the axial and radial impact load by the finite element method. The temperature field will be analyzed and studied also in this paper. The auxiliary bearing’s life will be evaluated. The scheme of auxiliary bearing and the simulation results offer the important theoretical base for this new auxiliary bearing style, and offer the protector design of the helium blower with AMB for HTR-10.
BibTeX:
@inproceedings{ISMB14_28,
  author = {Guojun Yang and Zhengang Shi and Xingnan Liu and Jingjing Zhao},
  title = {Research and Experiment of Auxiliary Bearings with No Lubrication for Helium Blower of HTR-10},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_28.pdf}
}
2014 Hutterer, M., Hofer, M., Nenning, T. and Schrödl, M. LQG Control of an Active Magnetic Bearing with a Special Method to Consider the Gyroscopic Effect Proceedings of ISMB14  
Abstract: It could be very difficult to find an acceptable feedback path for coupled differential equations like a FIVE degree of freedom (DOF) AMB system. This paper describes a linear quadratic Gaussian (LQG) approach on this problem. Due to the time variant gyroscopic part of the AMB system equation the controller could only be optimized for a specific angular velocity. For this reason a time variant state feedback is developed and added to the LQG controller in a way that the system is nearly equal for all angular velocities. The feedback matrix which is the result of the LQG problem uses all feedback terms. Compared to a decentralized controller which only uses the diagonal terms, the LQG method also uses the cross feedback terms which are able to provide instability. After developing the LQG method was compared to a decentralized PID controller.
BibTeX:
@inproceedings{ISMB14_29,
  author = {Markus Hutterer and Matthias Hofer and Thomas Nenning and Manfred Schrödl},
  title = {LQG Control of an Active Magnetic Bearing with a Special Method to Consider the Gyroscopic Effect},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_29.pdf}
}
2014 Zhang, K., Dai, X. and Dong, J. An Energy Storage Flywheel Supported by Hybrid Bearings Proceedings of ISMB14  
Abstract: Energy storage flywheels are important for energy recycling applications such as cranes, subway trains. In a petroleum field, a drilling platform runs with big load variation. A vertical flywheel energy storage system had been tested to stabilize the load fluctuation and proved its effectiveness. To improve bearing life and reliability, a new flywheel bearing system was designed. The key was the use of hybrid bearings including an axial permanent magnetic bearing (PMB), a lower end ball bearing and an upper end active magnetic bearing (AMB). The design effectively combined advantages of the different bearings. The original upper ball bearing was replaced with the AMB to avoid the use of a lubrication system for it and improve the damping ability for the rotor vibration modes. The vibration mode and the harmonic response were provided in the rotor dynamic analysis for the new flywheel rotor. The analysis results proved that the new rotor structure and the AMB design were appropriate.
BibTeX:
@inproceedings{ISMB14_3,
  author = {Kai Zhang and Xingjian Dai and Jinping Dong},
  title = {An Energy Storage Flywheel Supported by Hybrid Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_3.pdf}
}
2014 Pilat, A. Active Magnetic Bearing Interdisciplinary Design Modelling and Control Tool Proceedings of ISMB14  
Abstract: This elaboration presents a modern approach in the field of active magnetic bearing design based on computations supported by partial differential equations (PDEs) and ordinary differential equations (ODEs). The magnetic field problems are solved using the finite element method (FEM), while the levitating rotor motion is calculated using ODEs. The novel Active Magnetic Bearing Interdisciplinary Design Modelling and Control (AMBIDMC) study tool was developed customising COMSOL Multiphysics and MATLAB software. This paper summarises the author’s recent work in the field of integrated active magnetic levitation (AML) systems design and modelling including control and motion dynamics. A discussion of the features and limitations of the field of control systems is provided in this paper, showing how the developed model can be useful for controller studies. The discussion is illustrated by simulation data collected from working virtual prototypes.
BibTeX:
@inproceedings{ISMB14_30,
  author = {Adam Pilat},
  title = {Active Magnetic Bearing Interdisciplinary Design Modelling and Control Tool},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_30.pdf}
}
2014 Liu, S., Bian, Z., Fan, Y. and Zhang, Y. Zero-Power Control for Magnetic Bearings in Artificial Heart Pumps Proceedings of ISMB14  
Abstract: Artificial heart pump is a new approach to the treatment of heart failure, and the main representative of the third generation of pump is the application of the magnetic suspension or other suspension technology. Energy saving operation of artificial heart pump is very important. This paper studies the application of zero power control in the artificial heart pump. The model of zero power controller and operation theory is presented, and the stiffness characteristic of rotor under zero power control is analyzed. The control method to change equivalent stiffness of rotor system is given according to suspension position, verifying the results.
BibTeX:
@inproceedings{ISMB14_32,
  author = {Shuqin Liu and Zhongguo Bian and Youpeng Fan and Yunpeng Zhang},
  title = {Zero-Power Control for Magnetic Bearings in Artificial Heart Pumps},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_32.pdf}
}
2014 Li, D. and Liu, S. Magnetic Bearing Rotor Vibration Analysis Based on Harmonic Wavelet Transform Proceedings of ISMB14  
Abstract: Analysis of the magnetic bearing rotor vibration is the base of the optimizing design, supervise and diagnosis of the magnetic bearing. Harmonic wavelet package was used for the analysis of the vibration signal, the 1 dimension time domain signal was mapped to 2 dimension time-frequency plane, and the 3 dimension time frequency domain energy graph was constructed, then the analysis of the rotor vibration became intuitionistic and convenient. Via analysis of the time-frequency graph, the vibration in each time and each frequency was obtained. After the feature extraction from the time-frequency graph, the supervise and the diagnosis of the magnetic bearing can be realized.
BibTeX:
@inproceedings{ISMB14_33,
  author = {Deguang Li and Shuqin Liu},
  title = {Magnetic Bearing Rotor Vibration Analysis Based on Harmonic Wavelet Transform},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_33.pdf}
}
2014 He, Y., Sun, Z., Zhao, J., Shi, Z. and Shi, L. Comparison of a Model-Based and a Model-Free Unbalance Control Methods in Magnetic Bearing System Proceedings of ISMB14  
Abstract: Synchronous vibration caused by rotor imbalance is an obvious vibration problem in rotating machinery. Since active magnetic bearing has been proved to be an effective approach to solve this problem, many researchers have proposed various methods to reduce synchronous vibration and those methods can be classified into two categories: model-based method and mode-lfree method. In the paper, we use a model-free method, iterative learning control (ILC) and a model-based adaptive forced balancing methods (MBAFB) to attenuate synchronous vibration respectively and then compare their performances in several aspects. The results of this paper can provide references for the users to choose an appropriate unbalance control algorithm.
BibTeX:
@inproceedings{ISMB14_34,
  author = {Ying He and Zhe Sun and Jingjing Zhao and Zhengang Shi and Lei Shi},
  title = {Comparison of a Model-Based and a Model-Free Unbalance Control Methods in Magnetic Bearing System},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_34.pdf}
}
2014 Jayawant, R. and Davies, N. Field Experience with Automated Commissioning Tools in Both Remote and Local Commissioning of Active Magnetic Bearing Systems Proceedings of ISMB14  
Abstract: This paper describes field experience with 3rd generation AMB automated commissioning tools. This covers experience on “first of class” machinery on sites where both AMB specialists were present using the automated commissioning tools and other installations where no AMB specialist was present and all commissioning was conducted by remote guidance of local non-specialist staff and remote use of automated commissioning tools.
BibTeX:
@inproceedings{ISMB14_35,
  author = {Richard Jayawant and Nigel Davies},
  title = {Field Experience with Automated Commissioning Tools in Both Remote and Local Commissioning of Active Magnetic Bearing Systems},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_35.pdf}
}
2014 Kumar, P. and Jayawant, R. Design Synthesis and Experimental Validation of an AMB Controller with a Power Dense Amplifier for Retrofit Applications Proceedings of ISMB14  
Abstract: This paper describes the design, development and validation of a high power amplifier used to up-rate the axial power amplifiers of a standard AMB controller. The VA rating of the amplifiers was doubled whilst maintaining the original footprint of the amplifier. The thermal management and other constructional challenges presented by such up-rating and high power density are discussed, together with some of the techniques used to overcome them. This up-rated system is suitable for retrofit applications where the controller is coupled to pre-existing AMB hardware. Preliminary results from such an installation are presented.
BibTeX:
@inproceedings{ISMB14_36,
  author = {Praveen Kumar and Richard Jayawant},
  title = {Design Synthesis and Experimental Validation of an AMB Controller with a Power Dense Amplifier for Retrofit Applications},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_36.pdf}
}
2014 Nenning, T., Hofer, M., Hutterer, M. and Schrödl, M. Statistic Errors of Different Inform Evaluation Methods Applied to Magnetic Bearings Proceedings of ISMB14  
Abstract: Active magnetic bearings offer many advantages compared to conventional bearings. But due to economic reasons their field of application is relatively small. Self-sensing magnetic bearings can contribute to a significant decrease of the system costs, of course at limited accuracy in position detection compared to systems with sensors. The later on described INFORM method is one approach to self-sensing magnetic bearings. The position depending reluctance is measured through high frequent voltage injections and the resulting current slope. This paper discusses how different evaluation methods capable of calculating the current slope from the raw measurement data, differ in sensitivity and noise rejection. Therefore first the theoretical background of the used self-sensing method is explained. Next the error propagation of different evaluation methods is analysed and finally compared to measurements.
BibTeX:
@inproceedings{ISMB14_37,
  author = {Thomas Nenning and Matthias Hofer and Markus Hutterer and Manfred Schrödl},
  title = {Statistic Errors of Different Inform Evaluation Methods Applied to Magnetic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_37.pdf}
}
2014 Nenning, T., Hofer, M., Hutterer, M. and Schrödl, M. Setup with Two Self-Sensing Magnetic Bearings Using Differential 3-Active Inform Proceedings of ISMB14  
Abstract: This paper describes how a rotor with two radial self-sensing Hybrid Magnetic Bearings (HMB) with a novel self-sensing method is set up. Replacing position sensors with low cost alternatives currently is a broad field of research as it allows to decrease costs significantly. First the adapted version of the INFORM method in use is described in detail, explaining the advantages compared to the classic INFORM. Next the results of a 3D electro-magnetic finite element simulation are shown. The simulation was used to find an optimal geometry concerning the mutually exclusive goals of maximising bearing force and sensitivity / linearity of the INFORM method. Finally the simulation results are compared to measurements on the prototype.
BibTeX:
@inproceedings{ISMB14_38,
  author = {Thomas Nenning and Matthias Hofer and Markus Hutterer and Manfred Schrödl},
  title = {Setup with Two Self-Sensing Magnetic Bearings Using Differential 3-Active Inform},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_38.pdf}
}
2014 Komori, M., Takase, S., Nemoto, K., Sakai, N. and Asami, K.-I. Innovative Magnetic Levitation System by Using Persistent Current in Superconducting Coil Proceedings of ISMB14  
Abstract: Superconducting technique is applied to the levitation system. Persistent current in superconducting coil and control current in copper coil are used for levitating object and controlling object, respectively. The system is composed of a superconducting coil, a copper coil, a levitated object, a photo sensor, a PD controller, and power amplifiers. In this paper, basic study on superconducting coil and solenoid coil, and the dynamic characteristics of levitated object are performed. This may be the first trial that superconducting coil is used for magnetic levitation.
BibTeX:
@inproceedings{ISMB14_39,
  author = {Mochimitsu Komori and Shingo Takase and Kaoru Nemoto and Nobuo Sakai and Ken-Ichi Asami},
  title = {Innovative Magnetic Levitation System by Using Persistent Current in Superconducting Coil},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_39.pdf}
}
2014 Defoy, B., Alban, T. and Mahfoud, J. Energy Cost Assessment of the Active Control of a the Flexible Rotor Supported by AMB Proceedings of ISMB14  
Abstract: From a designer point of view, optimizing the energy necessary for the control is an important element that could lead to downsize the control cabinet and to an increase of margins according to power amplifier capabilities. Also, reducing the energy used, generates a less significant environmental impact. Two fuzzy logic based controllers were developed and assessed. First, the “Mechanical” performances are compared with respect to an augmented PID controller. Then, the energy necessary for the control is compared.
BibTeX:
@inproceedings{ISMB14_4,
  author = {Benjamin Defoy and Thomas Alban and Jarir Mahfoud},
  title = {Energy Cost Assessment of the Active Control of a the Flexible Rotor Supported by AMB},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_4.pdf}
}
2014 Smirnov, A., Pesch, A., Wroblewski, A., Pyrhönen, O. and Sawicki, J.T. Feedback Compensation of Tool Deflection in a High Speed AMB Machining Spindle Proceedings of ISMB14  
Abstract: This paper describes a method for compensation of tool tip deflection in a high-speed, magnetically levitated, machining spindle. The proposed method utilizes measurements from the AMB sensors to estimate forces and calculate the resulting tool deflections. The deflections are then compensated online with a feedback signal that changes the loaded tool tip’s position. The modeled results show significant performance improvements, which are experimentally validated.
BibTeX:
@inproceedings{ISMB14_40,
  author = {Alexander Smirnov and Alexander Pesch and Adam Wroblewski and Olli Pyrhönen and Jerzy T. Sawicki},
  title = {Feedback Compensation of Tool Deflection in a High Speed AMB Machining Spindle},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_40.pdf}
}
2014 Han, C., Xu, L. and Lin, Y. Researches on Substrates of High Temperature Eddy Current Sensor Proceedings of ISMB14  
Abstract: In this paper, substrates of eddy current sensor were composed by silver films and glass ceramic disks, all of these can resist high temperature . The thin silver films were deposited by radio frequency magnetron sputtering on machinable glass ceramic at room temperature. Variations of sputtering power, bios voltage and power density were carried out for each deposition, then parts of as-deposited samples were subjected to annealing at 600 ? within a vacuum chamber. Structural properties were studied by X-ray diffraction (XRD) and scanning electron microscope (SEM). It was shown that structural properties had a strong dependency on sputtering power and annealing temperature. Electrical contact resistance measured by a four point probe instrument was directly affected by the thickness of films. It was also found that the film conductivity, especially in thinner films, was improved by the increasing grain size. Further more, the film adhesion was observed by scratch tests experiment. Finally, the subsequent processes of high temperature eddy current sensor were introduced.
BibTeX:
@inproceedings{ISMB14_41,
  author = {Chao Han and Longxiang Xu and Yingzhe Lin},
  title = {Researches on Substrates of High Temperature Eddy Current Sensor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_41.pdf}
}
2014 Zhang, Y., Fang, J., Jiang, Y., Zhou, J. and Chen, Q. Analysis of Nonlinear Behavior in Power Amplifier of AMB System Proceedings of ISMB14  
Abstract: In order to make the AMB system satisfied the high energy-efficiency demands, the nonlinear behavior of H-bridge inverter, which is a power amplifier for AMB system, is studied in this paper. The discrete mapping model of the H-bridge inverter is established with some improvement using stroboscopic method. Based on this model, the dynamic evolution process of the inverter from stable state to chaos is directly exhibited, and the stable variation ranges of feedback gain and coil inductances are determined. Furthermore, a new simulation nonlinear model for an AMB system based on nonlinear H-Bridge inverter amplifier is set up, the influence of H-bridge inverter’s nonlinear behavior on the entire AMB system with two alternate change parameters is investigated. The simulation and experimental results demonstrate the existence of chaos phenomenon in AMB system and provide a stable range for AMB coil and control system design. The new AMB system model may have some benefits to the study of chaos control method for avoiding bifurcation and chaos phenomenon in AMB system.
BibTeX:
@inproceedings{ISMB14_42,
  author = {Yin Zhang and Jiancheng Fang and Yinxiao Jiang and Jinxiang Zhou and Qi Chen},
  title = {Analysis of Nonlinear Behavior in Power Amplifier of AMB System},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_42.pdf}
}
2014 Lee, K.-C., Baek, J.-Y., Kim, J.-W., Ahn, M.-H., Jung, T.-U. and Lee, M.-C. Design of Electromagnetic Levitation Linear Bearing for FPD Glass Delivery Applications Proceedings of ISMB14  
Abstract: In flat panel display (FPD) manufacturing, especially in next-generation organic light-emitting diode (OLED) display manufacturing, a high-weighted glass carrying tray is required to be position servo-controlled precisely in long range of vacuum process line without mechanical contact. So special contactless linear bearing, which is called a electromagnetic levitation linear bearing (ELLB) is suggested in this paper. It can expend its operating distance by adding series of electro-magnets and shifting the electromagnets by section switching algorithms suggested in reference [12]. In order to prove the feasibility of the ELLB, a test setup with specially designed ELLB is made-up and the performance of it is observed. With the proposed ELLBs and proper linear propulsion system, the glass-carrier system in vacuum FPD manufacturing process line is expected to be constructed easily in the near future.
BibTeX:
@inproceedings{ISMB14_43,
  author = {Ki-Chang Lee and Jun-Young Baek and Ji-Won Kim and Min-Hyuk Ahn and Tae-Uk Jung and Min-Cheol Lee},
  title = {Design of Electromagnetic Levitation Linear Bearing for FPD Glass Delivery Applications},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_43.pdf}
}
2014 Liu, X., Mo, N. and Zhou, Y. The Comparison of excitation source for sensors of the AMB system in HTGR Proceedings of ISMB14  
Abstract: Nowadays the High Temperature Gas-Cooled Reactor (HTGR) is developed widely over the world. A helium turbine of a 10 MW HTGR test module reactor with the core made of spherical fuel elements is under research at the Institute of Nuclear and New Energy Technology of Tsinghua University in China. In HTGR, the magnetic bearings are widely applied, where the rotating machineries are running under highly pure helium environment. Compared with conventional bearings, Active Magnetic Bearings (AMBs) possess several attractive advantages, such as contact-free, no-lubricating and active damping vibration. The sensors are the key components of the AMBs system and are responsible for measuring the position and movement of the rotor, the operating temperature and so on. In order to operate the sensors successfully, a stable and efficient excitation source is needed. The paper will present the design, simulation and test of Class AB and Class D type power amplifier excitation sources for the sensors of the AMBs system.
BibTeX:
@inproceedings{ISMB14_44,
  author = {Xiaohan Liu and Ni Mo and Yan Zhou},
  title = {The Comparison of excitation source for sensors of the AMB system in HTGR},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_44.pdf}
}
2014 Kailasan, A., Dimond, T. and Allaire, P. Energy Storage Flywheel Magnetic Bearing System - Magnetic Linear Circuit Vs. 3-D Finite Element Model Plus Electrical and Thermal Modeling Proceedings of ISMB14  
Abstract: A 1 kW-hr (3.6 MJ) energy storage flywheel with a design operating speed of 40,000 rpm and an inside-out flywheel has been designed and optimized. It is supported in two thrust and two radial active magnetic bearings. The purpose of this paper is to present the active magnetic bearing system modeling including the magnetic analysis. At the design stage, there are two ways to evaluate the magnetic bearing properties: linear circuit model or finite element model. The linear circuit models are simple lumped mass models. The finite element model discretizes the bearing geometry and the surrounding space and requires a great deal more work. There are not many full 3-D finite element magnetic bearing systems that have been fully compared to the equivalent linear circuit model. There are legitimate questions about accuracy of magnetic bearing modeling results. This paper considers these two approaches to compare the results for a realistic energy storage flywheel design. If the differences are large, it is expected that the 3-D finite element model is more likely to be accurate. This paper documents the differences for the flywheel magnetic bearing designs. The linear circuit model prediction of axial force capacity was 17% lower and the prediction of coil inductance was 8% lower than the predictions from 3-D finite element model. The linear circuit model of the radial bearing underestimated the force capacity by 14% and underestimated the inductance by 8.5% when compared to the 3D finite element model. Values were also compared for the open loop stiffness, current gain and force slew rate for both bearing designs. These relatively large differences in magnetic bearing performance parameters obtained between the linear circuit model and the 3-D finite element model, shows that the linear circuit model is not very accurate. Thus, the concern is that designing and optimizing a complex magnetic bearing supported device requires 3-D finite element modeling at the design stage. The flywheel has not been constructed and the magnetic bearings are thus not available for testing. It is hoped that this can be future work.
BibTeX:
@inproceedings{ISMB14_45,
  author = {Arunvel Kailasan and Tim Dimond and Paul Allaire},
  title = {Energy Storage Flywheel Magnetic Bearing System - Magnetic Linear Circuit Vs. 3-D Finite Element Model Plus Electrical and Thermal Modeling},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_45.pdf}
}
2014 Mendes, R.U., Daniel, G.B., de Castro, H.F. and Cavalca, K.L. Application of a Magnetic Actuator As an External Excitation Source in Fault Detection Proceedings of ISMB14  
Abstract: Rotating machinery covers a broad range of industrial applications. Consequently, unexpected failures may lead to suddenly manufacturing break-off involving high maintenance costs. The most common faults in such machines introduce anisotropy to the system causing changes in its modal parameters and increasing the response backward component. Modal analysis methods can be used to identify changes in the machine behavior and foresee incipient faults. This paper presents the time domain Multiple Output Backward Autoregression (MOBAR) method and discusses its advantages over frequency domain methods on field tests in industry. For the MOBAR method, a tuned non-synchronous excitation called blocking test is applied to the shaft using a magnetic actuator, and when the excitation is turned off, the decay response is used to estimate natural frequencies of the system and the corresponding modal damping. The changing of these parameters can be used to predict system failures. To demonstrate the usability of electromagnetic actuators to apply this method for fault diagnosis and identification, a case study is presented in which the directional coordinates modal parameters are identified for a rotor supported by journal bearings using the MOBAR technique.
BibTeX:
@inproceedings{ISMB14_46,
  author = {Ricardo Ugliara Mendes and Gregory Bregion Daniel and Helio Fiori de Castro and Katia Lucchesi Cavalca},
  title = {Application of a Magnetic Actuator As an External Excitation Source in Fault Detection},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_46.pdf}
}
2014 David, D., Santisteban, J. and Gomes, A.C.D.N. Interconnected Four Poles Magnetic Bearings Simulations and Testing Proceedings of ISMB14  
Abstract: This article proposes and analyses a new idea to be used in magnetic bearings. It is an adaptation of a structure that has already worked successfully in split-winding self-bearing motors. Preliminary theoretical results predict that a greater equivalent stiffness could be achieved when compared with the values associated with the traditional active magnetic bearing conception in the literature.
BibTeX:
@inproceedings{ISMB14_47,
  author = {Domingos David and Jose Santisteban and Afonso Celso Del Nero Gomes},
  title = {Interconnected Four Poles Magnetic Bearings Simulations and Testing},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_47.pdf}
}
2014 Tian, Y., Sun, Y. and Yu, L. Advanced Controller of a Hybrid Foil-Magnetic Bearing Proceedings of ISMB14  
Abstract: A hybrid foil-magnetic bearing (HFMB) is combination of a gas foil bearing (GFB) and a active magnetic bearing (AMB), which takes advantages of both bearings while compensating each other’s weaknesses. It is a solution of friction and wear of the GFBs at low speeds and limited load capacity of the AMBs. Furthermore, load sharing and control of dynamics can be achieved in a hybrid foilmagnetic bearing. However, in order to achieve the ideal performances of the HFMBs, an advanced controller must be designed based on the static and dynamic performances of the HFMBs. Since the AMBs are ‘smart’ devices that the working condition can be measured and actively controlled, it is quite natural to design an advanced controller for the HFMBs to use the AMBs to identify the characteristics of the GFBs and with the function of load sharing between the GFBs and the AMBs. In this paper, a 4-DOF model of bearing-rotor system supported by two HFMBs was established firstly, and then an advanced controller with the function of identification and load sharing was presented. Finally, experiments were done on a test rig whose rotor is supported by two journal HFMBs and a thrust AMB. The test results show that when change the load shared by the GFBs and the AMBs, advanced controller can find the new proper working position of the HFMBs rapidly and smoothly. More importantly, HFMBs with advanced controller based on the identified characteristics of GFBs can work steadily at the speed range of 0~2,2000r/min.
BibTeX:
@inproceedings{ISMB14_48,
  author = {Ye Tian and Yanhua Sun and Lie Yu},
  title = {Advanced Controller of a Hybrid Foil-Magnetic Bearing},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_48.pdf}
}
2014 Liu, P., Zhao, L., He, Y. and Zhang, K. Force Free Control in Active Magnetic Bearing Systems for the Magnetically Suspended Compound Molecule Pump Proceedings of ISMB14  
Abstract: A force free control method is studied based on the active magnetic bearings (AMBs) system of the magnetically suspended compound molecule pump. This method uses the feedforward strategy. The output signals generated with the least mean square (LMS) algorithm are the same as synchronous disturbances, which are caused by unbalance forces. So through this approaches, the controller need not respond to synchronous disturbances. This method can let the rotor rotate around its inertia axis and eliminate the synchronous disturbances of the currents in the electromagnet windings to significantly attenuate the mechanical vibration of the shell. The experimental results verify that the proposed approach is significantly minimized the amplitude of the shell vibration of the magnetically suspended compound molecule pump, which will provide good experience and design references for the future application of the AMBs in the molecule pump.
BibTeX:
@inproceedings{ISMB14_49,
  author = {Pingfan Liu and Lei Zhao and Ying He and Kai Zhang},
  title = {Force Free Control in Active Magnetic Bearing Systems for the Magnetically Suspended Compound Molecule Pump},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_49.pdf}
}
2014 Liu, B., Sjöberg, J. and Laiho, A. Optimization Based AMB Controller Design and Verification for Flexible Rotors Proceedings of ISMB14  
Abstract: Engineering costs especially for controller design are substantial and obstruct active magnetic bearings (AMBs) for broader industrial applications. An optimization based AMB controller design method is developed to solve this problem. The optimization criteria are selected to describe AMB practical performance. Controller components are chosen considering that parameters can be manually interpreted and modified onsite for commissioning. A multi-objective genetic algorithm (MOGA) toolbox is used to tune these controller component parameters to minimize the design criteria automatically. The method has been verified in a controller design process for an AMB levitated machine. With this method, the engineering cost for controller design can be reduced significantly.
BibTeX:
@inproceedings{ISMB14_5,
  author = {Bin Liu and Johan Sjöberg and Antti Laiho},
  title = {Optimization Based AMB Controller Design and Verification for Flexible Rotors},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_5.pdf}
}
2014 Rodriguez, E., de Santiago, J., Perez-Loya, J., Costa, F., Sotelo, G.G., Oliveira, J.G. and Stephan, R.M. Analysis of Passive Magnetic Bearings for Kinetic Energy Storage Systems Proceedings of ISMB14  
Abstract: This paper describes a passive magnetic bearing system intended to be used in a flywheel. The upper bearing consists of two rings of permanent magnets operating as a radial bearing. The lower bearing consists of high temperature superconductors in the stator and a permanent magnet cylindrical disk in the rotor, which contributes to the radial and axial stability of the system. Those bearings have been tested in an experimental rig specially designed for it. Measurements of the radial and axial forces, both static and dynamic, for different gaps are presented in this paper
BibTeX:
@inproceedings{ISMB14_50,
  author = {Elkin Rodriguez and Juan de Santiago and Jose Perez-Loya and Felipe Costa and Guilherme G. Sotelo and Janaina G. Oliveira and Richard M. Stephan},
  title = {Analysis of Passive Magnetic Bearings for Kinetic Energy Storage Systems},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_50.pdf}
}
2014 Hearn, C., Pratap, S., Chen, D. and Longoria, R. Superconducting Bearing Design for Outer Rotor Flywheel Using Lumped Parameter Techniques Proceedings of ISMB14  
Abstract: This paper describes the application of lumped parameter modeling techniques to designing high temperature superconducting bearings for outer-rotor flywheel energy storage systems. The lumped parameter models decrease computational time by 99% compared to Finite Element Analysis (FEM) without compromising fidelity needed to capture the non-linear and hysteretic force-displacement behavior between a levitated permanent magnet and bulk superconductor. The techniques formulated can be used to quickly evaluate lifting capacity and translational stiffness for a superconducting bearing design. The validity of the modeling approach has been verified by comparing results from FEM studies and experimental tests.
BibTeX:
@inproceedings{ISMB14_51,
  author = {Clay Hearn and Siddharth Pratap and Dongmei Chen and Raul Longoria},
  title = {Superconducting Bearing Design for Outer Rotor Flywheel Using Lumped Parameter Techniques},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_51.pdf}
}
2014 Ishino, Y., Takasaki, M. and Mizuno, T. Fablication of Non-Contact Carrier System Using Solar Magnetic Suspension Proceedings of ISMB14  
Abstract: A solar-powered magnetic suspension carrier system is fabricated which achieves noncontact power supply to the carrier. There are two conventional methods of supplying power to a carrier. One is through wires or contacts such as pantograph and the other is a battery in the carrier. However, the noncontact characteristics are lost in the former, and stations for charging the battery are necessary in the latter. These problems are overcome by the proposed carrier system using solar magnetic suspension that can achieve continuous levitation. In rooms like in factory, the generation of power by solar cells is low so that the magnetic suspension needs power saving. A zero power control system is applied to the suspension of the floator. In addition, low-power peripheral devices are also fabricated.
BibTeX:
@inproceedings{ISMB14_52,
  author = {Yuji Ishino and Masaya Takasaki and Takeshi Mizuno},
  title = {Fablication of Non-Contact Carrier System Using Solar Magnetic Suspension},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_52.pdf}
}
2014 Zhou, J., Fang, J., Zhang, Y. and Jiang, Y. Anti-Windup Control of Active Magnetic Bearings Subject to Voltage Saturation Proceedings of ISMB14  
Abstract: Active magnetic bearings (AMBs) have been widely applied in industrial rotating machinery. Power amplifier as an essential actuator of the AMB faces the limitation of DC bus voltage. A simple approach is to increase the voltage to a high value, but it has to deal with large current ripples and a low resolution. Other than the ordinary method, this paper addresses to the anti-windup control of AMB that aims to eliminate the adverse effect of the voltage saturation. The antiwindup algorithm is an addition to the nominal linear controller. And only when the saturation occurs is it activated. The stability is guaranteed by the procedure of calculating the linear matrix inequality (LMI) form of the regional Lyapunov stability. Simulation test is done to verify the proposed controller. Finally in the motor drive experiment, the axial AMB equipped in the prototype supports the thrust force. With the load changes, the performance of the anti-windup controller is demonstrated.
BibTeX:
@inproceedings{ISMB14_53,
  author = {Jinxiang Zhou and Jiancheng Fang and Yin Zhang and Yinxiao Jiang},
  title = {Anti-Windup Control of Active Magnetic Bearings Subject to Voltage Saturation},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_53.pdf}
}
2014 Toh, C.-S. and Chen, S.-L. Modeling and Control of a Hybrid Magnetic Bearing in a Ring-Type Flywheel System Proceedings of ISMB14  
Abstract: In this study, a hybrid magnetic bearing (HMB) is proposed for a ring-type flywheel system. The HMB is composed of passive and active units. The rotor weight will be fully supported by the lateral forces of the passive units. The other 4 DOFs will be levitated and controlled by the active units. We will first establish the magnetic force model of the passive and active units of the proposed HMB. With the magnetic force models in hand, a stabilizing levitation controller for the HMB is designed. Moreover, numerical simulation results verify the effectiveness of the controller.
BibTeX:
@inproceedings{ISMB14_54,
  author = {Chow-Shing Toh and Shyh-Leh Chen},
  title = {Modeling and Control of a Hybrid Magnetic Bearing in a Ring-Type Flywheel System},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_54.pdf}
}
2014 Stimac, G., Braut, S., Zigulic, R. and Skoblar, A. Robust Control and Loop Shaping Design with the Application to Flexible Rotor Levitated with AMBs Proceedings of ISMB14  
Abstract: The aim of this research is to ensure stable operation at a nominal rotation speed (above the first critical speed) of a flexible rotor levitated with active magnetic bearings (AMBs) and to guarantee good performance of the rotor/AMB system. Initially, minimizing the ITAE performance index, PID control system is designed to stabilize the rotor. The obtained transfer function is adopted as a compensator to shape the singular values of the nominal plant. By applying the Glover-McFarlane control method, a robust controller which includes coprime factor uncertainties is designed. The results show that the AMB system satisfies Zone A specifications defined by the ISO 14839 standard for newly commissioned machines with magnetic bearings.
BibTeX:
@inproceedings{ISMB14_55,
  author = {Goranka Stimac and Sanjin Braut and Roberto Zigulic and Ante Skoblar},
  title = {Robust Control and Loop Shaping Design with the Application to Flexible Rotor Levitated with AMBs},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_55.pdf}
}
2014 Zheng, S. and Feng, R. A Notch Filter for Magnetically Suspended Rotors Based on Rotating Coordinate Transformation Proceedings of ISMB14  
Abstract: Synchronous vibration are obstacles to the performance improvement of a rotating shaft supported by active magnetic bearings (AMBs). Based on the synchronous rotating coordinate transformation, this paper proposed a novel notch filter for the autobalancing of magnetically suspended rotors. After the analysis of the frequency characteristics of the novel notch filters, the calculating method of the convergence rate and comparison with the traditional notch filter are further investigated. Finally, the corresponding simulations and experiments are conducted. The results demonstrate that the novel notch filter has a good significant effect on the synchronous vibration of weakly gyroscopic rotors.
BibTeX:
@inproceedings{ISMB14_56,
  author = {Shiqiang Zheng and Rui Feng},
  title = {A Notch Filter for Magnetically Suspended Rotors Based on Rotating Coordinate Transformation},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_56.pdf}
}
2014 Lyu, X., Di, L., Yoon, S.Y., Lin, Z. and Hu, Y. Emulation of Energy Storage Flywheels on a Rotor-AMB Test Rig Proceedings of ISMB14  
Abstract: Because of their many appealing features, such as high specific energy, high specific power, ultra-compactness, short charging time (in minutes), long life span and no pollution, energy storage flywheels suspended on active magnetic bearings (AMBs) have drawn worldwide attention. In this paper, we use an existing rotor-AMB test rig to emulate the operation of energy storage flywheels suspended on AMBs. The test rig contains four active magnetic bearings, two located at the two ends of the rotor, one located at the rotor mid-span and the last located at the rotor quarter span. We will use the two magnetic bearings in the mid and quarter spans to emulate the negative stiffness of the generator and the gyroscopic effect of the flywheel disk. Simulation and experimental results are presented.
BibTeX:
@inproceedings{ISMB14_57,
  author = {Xujun Lyu and Long Di and Se Young Yoon and Zongli Lin and Yefa Hu},
  title = {Emulation of Energy Storage Flywheels on a Rotor-AMB Test Rig},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_57.pdf}
}
2014 Kasten, H. and Redemann, C. Influence on Unbalanced Magnetic Pull Proceedings of ISMB14  
Abstract: This article describes the effects of the unbalanced magnetic pull and the opportunities to suppress asymmetries of the air gap field.
BibTeX:
@inproceedings{ISMB14_58,
  author = {Henning Kasten and Christian Redemann},
  title = {Influence on Unbalanced Magnetic Pull},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_58.pdf}
}
2014 Basovich, S., Moha, T.B., Peretz, M., Arogeti, S. and Brand, Z. Switch-Mode Current Amplifier for Active Magnetic Bearings Proceedings of ISMB14  
Abstract: This paper presents the concept and the practical implementation of a switch-mode current amplifier for the use in Active Magnetic Bearings (AMB). The switch-mode amplifier consists of a full-bridge capable of operating in 2-level, 3- level or phase-shifted PWM mode. An optimal digital currentprogrammed mode controller lays out the foundations to a proximate-optimal, robust, large-signal dynamic response of the system under extreme cases of loading and parameters variations. In particular, the current amplifier developed is capable of following the desired reference for large inductance variations (due to displacement). The power stage combines a newly developed, efficient, passive-based current sensor that is capable of sensing bi-directional and near-zero currents, while being robust to external disturbances and maintaining simple and efficient structure. The presented current amplifier concept has been verified experimentally on a single-axis AMB platform using a dual channel amplifier prototype, controlled by a single 16 bit low-cost microcontroller.
BibTeX:
@inproceedings{ISMB14_59,
  author = {Sergei Basovich and Tomer Ben Moha and Mor Peretz and Shai Arogeti and Ziv Brand},
  title = {Switch-Mode Current Amplifier for Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_59.pdf}
}
2014 Xu, Y., Zhou, J., Di, L. and Xu, L. Active Magnetic Bearings for Rolling Element Bearings Outer Race Incipient Defect Diagnosis Proceedings of ISMB14  
Abstract: The active health monitoring of rotordynamic systems in the presence of bearing outer race defect is considered in this paper. The shaft is assumed to be supported by conventional mechanical bearings and an active magnetic bearing (AMB) is used in the mid of the shaft or outboard location as an actuator to apply constant force to the system. We present a nonlinear bearing-pedestal system model with the outer race defect under the AMB force. The nonlinear differential equations are integrated using the fourth-order Runge—Kutta algorithm in MATLAB and the simulation result is obtained. The simulation results show that the characteristic outer race defect signal is significantly amplified under the AMB force, which is helpful to improve the diagnosis accuracy of outer race defect.
BibTeX:
@inproceedings{ISMB14_6,
  author = {Yuanping Xu and Jin Zhou and Long Di and Longxiang Xu},
  title = {Active Magnetic Bearings for Rolling Element Bearings Outer Race Incipient Defect Diagnosis},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_6.pdf}
}
2014 Di, L., Zhou, J., Chen, C. and Lin, Z. Experimental Verification of a Rotor Unbalance Response Based Approach to the Identification of Magnetic Bearing Support Parameters Proceedings of ISMB14  
Abstract: The support parameters, the stiffness and damping coefficients, of active magnetic bearings (AMBs) have direct influence on the dynamic response and stability of a rotor bearing system. The unbalance response method is a simple but effective way to identify the AMB support parameters. In this paper, we present experimental verification of this identification method. We first briefly introduce the unbalance response method and the error response surface approach to rectifying the identification error induced by the rotor flexibility. The final AMB stiffness and damping coefficients are determined as the sum of the nominal values identified by the unbalance response method and the identification errors derived from the error response surfaces. We will then present the experimental verification of this combined unbalance response and error response surface identification method on a rotor AMB test rig. In order to verify the identification method, the parameters thus identified based on the experimental data are integrated with the rotor finite element model to form the rotor-AMB model. The model unbalance response is obtained through simulation and compared with experimentally measured unbalance response. The close agreement between the model unbalance response and the experimentally measured response demonstrates that the proposed method is effective in identifying the AMB support parameters.
BibTeX:
@inproceedings{ISMB14_60,
  author = {Long Di and Jin Zhou and Changli Chen and Zongli Lin},
  title = {Experimental Verification of a Rotor Unbalance Response Based Approach to the Identification of Magnetic Bearing Support Parameters},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_60.pdf}
}
2014 Ariga, Y., Saitoh, Y. and Watanabe, K. Controller Structure for Magnetic Bearing for Achieving Both Unbalance Suppression and Stabilization Proceedings of ISMB14  
Abstract: This study proposes a control system in which the controller structure is divided in consideration of the unstable zeros of the controller. This controller can both inhibit a sine wave disturbance intended to produce unbalanced vibrations and stabilize the system with desired bearing stiffness. The effectiveness of the proposed method is verified through a simulation.
BibTeX:
@inproceedings{ISMB14_61,
  author = {Yuichi Ariga and Yohei Saitoh and Keiji Watanabe},
  title = {Controller Structure for Magnetic Bearing for Achieving Both Unbalance Suppression and Stabilization},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_61.pdf}
}
2014 Sugimoto, H., Tanaka, S. and Chiba, A. Reduction of Rotor Vibration in Passively Stabilized Direction in Single-Drive Bearingless Motor Proceedings of ISMB14  
Abstract: In this paper, an improvement of the rotor vibration in one-axis actively positioned single-drive bearingless motor (SDBM) with repulsive passive magnetic bearings is presented. The SDBM has only one set of three-phase windings. It generates both torque and active axial force independently driven by only one three-phase inverter and one displacement sensor. Therefore, the single-drive bearingless motors have the advantages of low cost and small size. Only axial z-axis is actively positioned. The other axes, radial movements x and y, and tilting movements ? x and ? y, are passively stable. Therefore, in the one degree-of-freedom (1DOF) bearingless motor, vibrations in the radial and tilting directions are serious problem. In this paper, an improvement method of the radial vibration in the 1DOF SDBM is presented. The principle of the radial vibration generation is shown. In the experiment, it is found that a correction of the rotor rotational angular position is effective for the radial vibration reduction.
BibTeX:
@inproceedings{ISMB14_62,
  author = {Hiroya Sugimoto and Seiyu Tanaka and Akira Chiba},
  title = {Reduction of Rotor Vibration in Passively Stabilized Direction in Single-Drive Bearingless Motor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_62.pdf}
}
2014 Ueno, S., Fukuura, T. and Toan, T.V. A 5-DOF Active Controlled Disk Type PM Motor with Cylindrical Flux Paths Proceedings of ISMB14  
Abstract: This paper proposes a novel disk type permanent magnet motor, which actively controls 5 degrees of freedom of a flat rotor without any contact. The proposed motor consists of an Axial Self-bearing Motor (ASBM) and additional cylindrical flux paths. The axial force and motor torque are controlled by the rotating flux with the same number of poles of the rotor, and the tilt control torque is produced by the rotating flux with the two plus or two minus poles of the rotor. The radial force is produced by supplying direct current to the stator windings. The direct current produces the flux through the stator and the cylindrical flux path, then the radial force can be generated by the interaction of the rotor poles and the edge of the cylindrical flux path. This paper introduces the structure and principle of the proposed motor, and shows the results of the magnetic forces calculated by the numerical electromagnet analysis.
BibTeX:
@inproceedings{ISMB14_63,
  author = {Satoshi Ueno and Takuya Fukuura and Tran Van Toan},
  title = {A 5-DOF Active Controlled Disk Type PM Motor with Cylindrical Flux Paths},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_63.pdf}
}
2014 Uemura, Y., Nakahata, T. and Chiba, A. Vibration Suppression of A Middle-Point Current-Injection Type Bearingless Motor at 50000r/min Proceedings of ISMB14  
Abstract: With the developments of power electronics technology and increments of rotational speed of motors, a critical speed is one of the problems. Vibration of rotational shaft has been reported to be suppressed by magnetic force of bearingless motors. In general bearingless motors, motor windings and suspension windings are separately enclosed in the stator slot. For only vibration suppression at a critical speed, however, suspension windings are not used except the critical speed. In this paper, vibration suppression of a rotor shaft by a middle-point current-injection type bearingless motor at 50000 r/min is presented. This motor can generate the torque and the magnetic force by only one set of three-phase windings. The test results of the vibration suppression are presented.
BibTeX:
@inproceedings{ISMB14_64,
  author = {Yusuke Uemura and Takayuki Nakahata and Akira Chiba},
  title = {Vibration Suppression of A Middle-Point Current-Injection Type Bearingless Motor at 50000r/min},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_64.pdf}
}
2014 Impinna, F., Detoni, J.G., Tonoli, A. and Amati, N. Test and Theory of Electrodynamic Bearings Coupled to Active Magnetic Dampers Proceedings of ISMB14  
Abstract: Electrodynamic bearings (EDBs) are passive magnetic bearings that exploit the interaction between eddy currents developed in a rotating conductor and a static magnetic field to generate forces. Similar to other types of magnetic suspensions, EDBs provide contactless support, thus avoiding problems with lubrication, friction and wear. Electrodynamic bearings have also drawbacks such as the difficulty in insuring a stable levitation in a wide speed range. The paper presents a solution where the EDBs are coupled with active magnetic dampers (AMDs) to guarantee a stable levitation.
BibTeX:
@inproceedings{ISMB14_65,
  author = {Fabrizio Impinna and Joaquim Girardello Detoni and Andrea Tonoli and Nicola Amati},
  title = {Test and Theory of Electrodynamic Bearings Coupled to Active Magnetic Dampers},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_65.pdf}
}
2014 Mönch, I., Melzer, M., Bahr, F., Makarov, D., Hofmann, W. and Schmidt, O.G. Ultra-Thin and Flexible Hall Effect Sensorics Proceedings of ISMB14  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB14_66,
  author = {Ingolf Mönch and Michael Melzer and Falk Bahr and Denys Makarov and Wilfried Hofmann and Oliver G. Schmidt},
  title = {Ultra-Thin and Flexible Hall Effect Sensorics},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_66.pdf}
}
2014 Liu, J., Ding, G., Gao, B. and Zhang, B. Giant Magnetostrictive Material-Fiber Bragg Grating Magnetic Field Sensors Used in Magnetic Bearings Proceedings of ISMB14  
Abstract: A novel FBG-GMM sensor was proposed to measure magnetic flux density, in which the FBG was stuck perpendicular to the GMM’s principal magnetostriction orientation to make a thin-slice sensor. The FBG-GMM magnetic field sensor’s properties were tested on a U-shape electromagnet test setup, the measured data were consistent with the theoretical prediction and the sensor’ linear range is from 0.2T to 0.6T. The FBG-GMM magnetic field sensor was introduced to measure a radial magnetic bearing’s air-gap flux density. Static flux density measurement was performed through two FBG-GMM sensors and one temperature compensation FBG, and the measured data were consistent with the sensor properties obtained from the U-shape electromagnet test, which validate the FBG-GMM magnetic field sensor’s feasibility.
BibTeX:
@inproceedings{ISMB14_67,
  author = {Jiayi Liu and Guoping Ding and Bin Gao and Biyun Zhang},
  title = {Giant Magnetostrictive Material-Fiber Bragg Grating Magnetic Field Sensors Used in Magnetic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_67.pdf}
}
2014 Ni, T., Wang, X., Ding, Q. and Wu, G. Two Mathematical Models of Five-Phase High Speed Permanent Magnet bearingless Slice Motor Proceedings of ISMB14  
Abstract: Most bearingless motors run at a relatively low speed because of the high iron loss problem. Considering that a slotless structure is beneficial to high speed, this paper deduces two mathematical models based on this existent structure. The first model is for traditional control and the second one is for fault-tolerant control. In the process of derivation, the concept of superposition is introduced to calculate the flux density in the air gap. At last, finite element analysis is done to verify the model.
BibTeX:
@inproceedings{ISMB14_68,
  author = {Tuocheng Ni and Xiaolin Wang and Qiang Ding and Guyu Wu},
  title = {Two Mathematical Models of Five-Phase High Speed Permanent Magnet bearingless Slice Motor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_68.pdf}
}
2014 Siegl, G., Tzianetopoulou, T. and Denk, J. Simulation and Experimental Validation of a 9t AMB Rotor Landing in Rolling Element Back-Up Bearings Proceedings of ISMB14  
Abstract: Backup Bearings (BuB) must be designed to withstand the shock loads which occur during impacts with heavy and/or high-speed rotors. Both experimental testing and transient dynamic simulation are necessary for the study of BuB performance. This paper presents the transient dynamic simulation methodology developed within SIEMENS for the study of full-scale rotor landings in rolling element BuBs. The developed models were validated with a substantial landing program led and performed by SIEMENS, whose objective was to qualify the safe operation of hybrid rolling element BuBs for an industrial application utilizing an AMB-levitated 9t supercritical motor. The paper describes the BuB model, summarizes the simulation results and offers a comparison with experimental measurements from the aforementioned successful landing tests program.
BibTeX:
@inproceedings{ISMB14_69,
  author = {Guenther Siegl and Theodora Tzianetopoulou and Joachim Denk},
  title = {Simulation and Experimental Validation of a 9t AMB Rotor Landing in Rolling Element Back-Up Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_69.pdf}
}
2014 Stusak, M. Eddy Current Sensors for Magnetic Bearings of the Textile Spinning Machines Proceedings of ISMB14  
Abstract: The position sensors for magnetic bearings are very important parts of such a system. It is possible to say they are one of the most exacting part there because lot of conflicting demands are posed on them. This presentation describes the sensors for textile spinning machines which must have not only usual technical features but, in addition, they should fulfill the specific requirements of this industry, especially functionality in very dusty environment, resistance against foreign magnetic fields and last not least also potential for economical mass production without individual hardware setting and without selecting of specific components. Simply told, the prices at this market segment are forced down but the quality and reliability must be kept high.
BibTeX:
@inproceedings{ISMB14_7,
  author = {Miroslav Stusak},
  title = {Eddy Current Sensors for Magnetic Bearings of the Textile Spinning Machines},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_7.pdf}
}
2014 Lusty, C., Sahinkaya, N. and Keogh, P. A Novel Twin-Shaft Rotor with Active Magnetic Couplings for Vibration Control Proceedings of ISMB14  
Abstract: A novel rotor topology is proposed with the goal of reducing vibration in high speed rotor systems. Primarily, reduction in synchronous vibration at critical speeds is targeted. In essence, the novel topology consists of a hollow tube rotor coupled to a secondary non-rotating shaft through a number of actively managed magnetic couplings. An outline of the new topology is provided, along with a finite element analysis comparing the out-of-balance vibration response of the proposed rotor to a comparable simple rotor. Designs for a test rig based on this topology are presented, together with an outline of anticipated testing and potential future development of the idea.
BibTeX:
@inproceedings{ISMB14_70,
  author = {Chris Lusty and Necip Sahinkaya and Patrick Keogh},
  title = {A Novel Twin-Shaft Rotor with Active Magnetic Couplings for Vibration Control},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_70.pdf}
}
2014 Kamijo, Y., Ito, H. and Maruyama, Y. Structures and Characteristics of Magnetic Bearing with Zero Power Controlled Electromagnetic Suspension Proceedings of ISMB14  
Abstract: This paper proposes a new magnetic bearing in order to decrease rotor eccentricity and power consumption. The proposed bearing system consists of moving frames, suspensions, permanent magnets, electromagnets and Zero Power controller. The system enables to avoid rotor touchdowns. A clearance between a rotor and our proposed bearing may be increased compared to conventional electromagnetic bearings. The paper shows the experimental results to verify testing system.
BibTeX:
@inproceedings{ISMB14_71,
  author = {Yoshitake Kamijo and Hiroaki Ito and Yutaka Maruyama},
  title = {Structures and Characteristics of Magnetic Bearing with Zero Power Controlled Electromagnetic Suspension},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_71.pdf}
}
2014 Reischl, D., Dorninger, A., Fohler, A., Gerstmayr, J., Koppelstätter, W., Silber, S. and Weitzhofer, S. Coupled Mechanical and Electromagnetic Optimization of High Speed Rotors Proceedings of ISMB14  
Abstract: Optimizing mechatronic systems is of increasing importance, for example, to minimize the consumption of resources and energy during operation and production. The optimization objectives for rotordynamic systems are, for instance, critical resonances, durability and costs. In order to meet such objectives, good optimization algorithms as well as simulation tools for each physically relevant effect for the problem are required. In this paper, we present the coupling of the optimization software MagOpt and the mechatronic simulation tool HOTINT and an application of the system.
BibTeX:
@inproceedings{ISMB14_72,
  author = {Daniel Reischl and Alexander Dorninger and Armin Fohler and Johannes Gerstmayr and Werner Koppelstätter and Siegfried Silber and Simon Weitzhofer},
  title = {Coupled Mechanical and Electromagnetic Optimization of High Speed Rotors},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_72.pdf}
}
2014 Detoni, J.G., Impinna, F., Amati, N., Tonoli, A., Piccolo, M.P. and Genta, G. Stability of a 4 degree of freedom rotor on electrodynamic passive magnetic bearings Proceedings of ISMB14  
Abstract: Electrodynamic bearings exploit repulsive forces due to eddy currents to produce positive stiffness by passive means without violating the Earnshaw stability criterion. This remarkable characteristic makes this type of bearing a suitable alternative to active magnetic bearings in fields such as kinetic energy storage flywheels, turbo pumps, high speed compressors, among others. However, the suspension can become unstable due to rotating damping. To obtain deeper understanding of this instability phenomenon this paper presents the analysis of stability of a four degree of freedom (4dof) rotor supported by electrodynamic bearings. The 4dof rotor model is coupled to the dynamic model of the eddy current forces generated by the electrodynamic bearing and the stability of the complete system is analyzed. This model is used to study the stability of both cylindrical and conical whirling motion of the rotor. In addition to the well known cylindrical whirl instability the possible occurrence of conical instability is demonstrated. Finally the effects of two stabilization strategies are analyzed.
BibTeX:
@inproceedings{ISMB14_73,
  author = {Joaquim Girardello Detoni and Fabrizio Impinna and Nicola Amati and Andrea Tonoli and Maria Pina Piccolo and Giancarlo Genta},
  title = {Stability of a 4 degree of freedom rotor on electrodynamic passive magnetic bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_73.pdf}
}
2014 Ooshima, M. and Gomi, Y. Characteristics of Torque and Suspension Force in a d-q Axis Current Control Bearingless Motor Proceedings of ISMB14  
Abstract: This paper presents the characteristic of torque and suspension force in a d-q axis current control bearingless motor. It is derived based on Finite Element (FE) analysis using a simulation software, and furthermore compared with the computed results of the conventional bearingless motors, which two kinds of windings for motor drive and magnetic suspension are wound in a stator core. Three types of the conventional bearingless motor with n-pole motor winding and (n +- 2)-pole suspension winding are taken up and their computed results of the torque and suspension force are discussed in detail. As a result, the superiority of the proposed d-q axis current control bearingless motor is found.
BibTeX:
@inproceedings{ISMB14_74,
  author = {Masahide Ooshima and Yuto Gomi},
  title = {Characteristics of Torque and Suspension Force in a d-q Axis Current Control Bearingless Motor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_74.pdf}
}
2014 Mikota, G., Proell, A. and Silber, S. Experimental Modal Analysis of a Gyroscopic Rotor in Active Magnetic Bearings Proceedings of ISMB14  
Abstract: For a gyroscopic rotor in active magnetic bearings, the rigid body natural frequencies and mode shapes are investigated. An impulsive excitation force is generated by two rectangular pulses in the current control reference signal. With vibration measurements available in two perpendicular directions for each bearing, experimental modal analyses are performed at rotational speeds up to 100000 rpm. Identification results demonstrate the gyroscopic split of natural frequencies.
BibTeX:
@inproceedings{ISMB14_75,
  author = {Gudrun Mikota and Andreas Proell and Siegfried Silber},
  title = {Experimental Modal Analysis of a Gyroscopic Rotor in Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_75.pdf}
}
2014 Denk, J., Koehler, B.-U., Siegl, G. and Siebke, P. Landing Tests with a 6300rpm, 9t AMB Rotor in Rolling Element Back-Up Bearings Proceedings of ISMB14  
Abstract: This article describes a systematic approach to qualify backup bearings for very large rotors levitated by active magnetic bearings (AMB). The approach comprises dynamic simulations of the landing events prior to the testing with good prediction quality as part of the safety concept. The approach was applied for the backup bearing qualification of a 9t rotor with a rotational speed up to 6420rpm. The results of the landing tests are shown and compared with the simulation results.
BibTeX:
@inproceedings{ISMB14_76,
  author = {Joachim Denk and Bert-Uwe Koehler and Guenther Siegl and Peter Siebke},
  title = {Landing Tests with a 6300rpm, 9t AMB Rotor in Rolling Element Back-Up Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_76.pdf}
}
2014 Lopes, J.S.B., dos Santos, L.P., de Paiva, J.A., Victor, V.F., Maitelli, A.L. and Salazar, A.O. Rotor Flux Observer Based Neuro-Fuzzy Techniques to Speed Vector Control of a Bearingless AC Motor Proceedings of ISMB14  
Abstract: This study presents the problem of rotor flux orientation control of bearingless induction motor. The key of this solution is the estimation of rotor flux. This work applied an inference system using fuzzy logic and the neural networks with the MATLAB(R). The Adaptive Neuro-Fuzzy Inference System (ANFIS) is based in an input-output model. ANFIS is used to tune the membership functions in fuzzy system and utilize the backpropagation learning algorithm. This system was applied to estimate the rotor flux and the magnetization current of the purpose of identifying bearingless induction motor angular speed. The hybrid estimator aims at compensating possible parametric variations of the machine caused by agents such as temperature or nucleus saturation. The simulated results showed good performance. The results demonstrated the feasibility of the proposed technique. The ANFIS estimator proposed will be embedded in the DSP TMS 3208F28335 in future works.
BibTeX:
@inproceedings{ISMB14_77,
  author = {Jose Soares Batista Lopes and Luciano Pereira dos Santos and Jose Alvaro de Paiva and Valci F. Victor and Andre L. Maitelli and Andres O. Salazar},
  title = {Rotor Flux Observer Based Neuro-Fuzzy Techniques to Speed Vector Control of a Bearingless AC Motor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_77.pdf}
}
2014 Xu, Z. and Ahn, J.-W. Eccentricity Analysis and Efficiency Estimation of 12/14 Hybrid Stator Pole Bearingless SRM Proceedings of ISMB14  
Abstract: The radial force to suspend the rotor in a constant air-gap for bearingless switched reluctance motor (BLSRM) is dependent on air-gap and force current. Due to the non-linear characteristic of inductance, the radial force is much affected by the rotor eccentricity. In order to keep constant air-gap of rotor, the nonlinear characteristics of eccentricity should be analyzed. Further, the auxiliary bearing is always used to restrict the maximum eccentricity of the rotor in industry. In this paper, the rotor eccentricity effect in the proposed 12/14 BLSRM is analyzed. Meanwhile, the efficiency of the 8/10 and proposed BLSRMs is estimated. The analysis results further verify the validity of the proposed BLSRM.
BibTeX:
@inproceedings{ISMB14_78,
  author = {Zhenyao Xu and Jin-Woo Ahn},
  title = {Eccentricity Analysis and Efficiency Estimation of 12/14 Hybrid Stator Pole Bearingless SRM},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_78.pdf}
}
2014 Shinshi, T., Hijikata, W., Mamiya, T. and Takatani, S. Development of Extracorporeal Maglev Blood Pumps Proceedings of ISMB14  
Abstract: In centrifugal blood pumps, contactless support of the impeller and a sufficient fluid gap in the pump head have been identified as features that have the potential to keep blood damage to a minimum and enhance the durability of the blood pump. We have developed three types of cost-effective magnetic bearings and contactless torque transmission mechanisms for disposable centrifugal blood pumps which can be used for extracorporeal circulation. In this paper, we introduce prototype maglev centrifugal blood pumps that utilize these mechanisms and we present both the experimental results and the results of simulations carried out on them.
BibTeX:
@inproceedings{ISMB14_79,
  author = {Tadahiko Shinshi and Wataru Hijikata and Taichi Mamiya and Setsuo Takatani},
  title = {Development of Extracorporeal Maglev Blood Pumps},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_79.pdf}
}
2014 Okada, Y., Suzuki, H., Matsuda, K.-I., Kondo, R. and Enokizono, M. Development of Highly Efficient Magnetic Bearing and Application to Ultra-Low Temperature Fluid Pump Proceedings of ISMB14  
Abstract: Highly efficient hybrid type magnetic bearing is proposed in this paper. It is intended to apply the proposed magnetic bearing to ultra low temperature fluid pump. Traditional low temperature pump is supported by a ceramic ball bearing which is damaged by the low temperature liquid. Non-contact support is highly requested. However, the standard electro-magnetic bearing consumes high electric power causing heat to the liquid. This paper proposes highly efficient hybrid type radial magnetic bearing which can operate with very low power consumption. Also the pump is canned by the FRP pipe which has thick wall to separate the stator from the liquid. The designed magnetic bearing has 3 [mm] wide air gap with high force factor.
BibTeX:
@inproceedings{ISMB14_8,
  author = {Yohji Okada and Hironari Suzuki and Ken-Ichi Matsuda and Ryou Kondo and Masato Enokizono},
  title = {Development of Highly Efficient Magnetic Bearing and Application to Ultra-Low Temperature Fluid Pump},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_8.pdf}
}
2014 Osa, M., Masuzawa, T., Omori, N. and Tatsumi, E. Radial Position Active Control of Double Stator Axial Gap Self-Bearing Motor for Paediatric VAD Proceedings of ISMB14  
Abstract: A novel axial gap double stator self-bearing motor which can control five-degrees of freedom (5-DOF) of rotor postures have been developed for paediatric ventricular assist device (VAD). The motor has a top stator, a bottom stator and a levitated rotor driven as a synchronous permanent magnet motor. The rotor is axially suspended between the stators which have an identical structure. A double stator mechanism enhances a higher torque production and realizes radial position active control. This paper proposes a concept of radial position active control and magnetic suspension ability of developed selfbearing motor. The rotor is successfully levitated and rotated up to 6400 rpm without any physical contact with 5-DOF active control in air. The radial oscillation amplitudes are actively suppressed with the proposed radial position control concept. The developed 5-DOF controlled self-bearing motor which is suitably miniature as an actuator for paediatric VAD indicates sufficient capability of the magnetic levitation and non-contact rotation.
BibTeX:
@inproceedings{ISMB14_80,
  author = {Masahiro Osa and Toru Masuzawa and Naoki Omori and Eisuke Tatsumi},
  title = {Radial Position Active Control of Double Stator Axial Gap Self-Bearing Motor for Paediatric VAD},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_80.pdf}
}
2014 dos Santos, L.P., Lopes, J., Victor, V., Maitelli, A. and Salazar, A. Robust Speed Controller of a Bearingless AC Motor Type Divided Winding, Based on a Conventional Squirrel Cage Induction Motor Proceedings of ISMB14  
Abstract: This paper shows a new approach to control the speed of rotor field oriented for a bearingless AC Motor type divided winding for a conventional squirrel cage Induction Motor of 3.75 kW, 380V, 4-poles, 60Hz, 1.04 Nm. To implement the control strategies, was chosen the rotor flux referential (R-FOC). This referential is based on decomposition of the stator current into two components done in a decoupled manner: flux controlled by stator direct-axis current and torque controlled by quadrature-axis current. To implement the control algorithm, was chosen the rotor flux referential, which is being estimated through the stator winding currents and the rotor speed. The vectorial speed controller operates in synchronism with the radial positioning controller, but these controllers should work with low mutual influence.
BibTeX:
@inproceedings{ISMB14_81,
  author = {Luciano Pereira dos Santos and Jose Lopes and Valci Victor and Andre Maitelli and Andres Salazar},
  title = {Robust Speed Controller of a Bearingless AC Motor Type Divided Winding, Based on a Conventional Squirrel Cage Induction Motor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_81.pdf}
}
2014 He, Y., Nonami, K. and Shimizu, F. A Method of Simple Adaptive Control for MIMO Nonlinear AMB-Flywheel Levitation System Proceedings of ISMB14  
Abstract: In this paper, AMB-flywheel is desirable to minimize the energy required for its stabilization control. We propose a design method for performing SAC control for a MIMO AMB-flywheel system with five degrees of freedom; The SAC controller was proposed for application to an AMB-flywheel system and control performance was improved by combining SAC with PID controller. The PID based SAC controller is evaluated via experiments. We present the analysis results of the influence of external disturbances from the EV driving on the road and high-speed rotation experimental results about the AMB-flywheel system. The results demonstrate that the SAC controller is feasible and effective.
BibTeX:
@inproceedings{ISMB14_82,
  author = {Yong He and Kenzo Nonami and Fumiya Shimizu},
  title = {A Method of Simple Adaptive Control for MIMO Nonlinear AMB-Flywheel Levitation System},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_82.pdf}
}
2014 Kluyskens, V. and Dehez, B. Optimization of a New Radial Electrodynamic Damper Proceedings of ISMB14  
Abstract: The study of electrodynamic dampers is an important point when working with electrodynamic bearings. These dampers may also be used in combination with reluctant passive magnetic bearings. This paper proposes a new design of a robust and inherently stable radial electrodynamic damper with a homopolar axial magnetic flux. An optimization, based on finite element models, of this new bearing topology is made. For this to be possible, a 2-D representation of the damper is developed equivalent to the 3-D damper. The results of the optimizations are presented and a discussion of the influence of some of the parameters is done.
BibTeX:
@inproceedings{ISMB14_83,
  author = {Virginie Kluyskens and Bruno Dehez},
  title = {Optimization of a New Radial Electrodynamic Damper},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_83.pdf}
}
2014 Shimizu, F. and Nonami, K. Benchmark and Verification of Control Algorithm for Flywheel with Active Magnetic Bearing on Electric Vehicle and Proposal of New SAC Algorithm ($1 modification and bias variable $p approach) Proceedings of ISMB14  
Abstract: This paper presents the requirements which a good rotor controller of flywheel energy storage system (FESS) with Active Magnetic Bearing (AMB) on Electric Vehicle (EV) should satisfy. AMB-FESS is used for energy regeneration. The dynamics of the flywheel rotor on EV is very complex and to compare various features a benchmark is necessary. Controllers are evaluated according to certain criteria as used by many motor companies. Controllers are selected to satisfy the design requirements prescribed by many motor companies. Thus the robust adaptive controllers were chosen and benchmarked using simulations and experiments. The investigation revealed that a controller with high rigidity gain and a reference model can not only suppress disturbance effects but also lower power consumption. Therefore Simple Adaptive Control with epsilon1 modification and bias variable gamma P approach is proposed. The utility of the new controller experimentally was proven.
BibTeX:
@inproceedings{ISMB14_84,
  author = {Fumiya Shimizu and Kenzo Nonami},
  title = {Benchmark and Verification of Control Algorithm for Flywheel with Active Magnetic Bearing on Electric Vehicle and Proposal of New SAC Algorithm ($1 modification and bias variable $p approach)},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_84.pdf}
}
2014 Quurck, L., Schaede, H., Richter, M. and Rinderknecht, S. High Speed Backup Bearings for Outer-Rotor-Type Flywheels - Proposed Testrig Design Proceedings of ISMB14  
Abstract: Magnetic levitated rotors for high speed applications need backup bearing (BB) for safe spin down or relevitation after magnetic bearing failure or overload situations. Especially in flywheel energy storage systems long spin down times due to the high kinetic energy content and the vacuum environment complicate the use of conventional bearings as BBs. Depending on the geometric dimension, the rotational speed of the rotor and associated rotordynamic effects today’s available bearings (usually rolling element bearings) cannot fulfill their task with the desired lifetime. This paper shows mechanical and thermal problems as well as approaches to mitigate them. For a built and tested Outer-Rotor-Type flywheel its BB system is discussed. For an increase of the surface velocity limit and the extension of the BB lifetime several design improvements are suggested. Properties of a test rig and its special rotor design for BB testing are described and proposed for further experimental investigation. A design of the test-BB is proposed and the data acquisition as well as the dynamic behavior of the rotor is described.
BibTeX:
@inproceedings{ISMB14_85,
  author = {Lukas Quurck and Hendrik Schaede and Michael Richter and Stephan Rinderknecht},
  title = {High Speed Backup Bearings for Outer-Rotor-Type Flywheels - Proposed Testrig Design},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_85.pdf}
}
2014 Cole, M., Jimenez, S. and Keogh, P. Feedback Control of a Magnetic Bearing Using Fusion of Rotor Acceleration and Position Measurements Proceedings of ISMB14  
Abstract: This paper considers controlling a magnetic bearing using combined feedback of rotor acceleration and position measurements. A controller design based on sensor fusion via complementary filtering is described. The control method can maintain stability while allowing the cross-over frequency for the acceleration and position feedback loops to be set arbitrarily. In this way, position measurements can be utilized primarily for disturbance cancellation over a low frequency band while acceleration feedback maintains bearing stability and disturbance rejection over a higher frequency band. The approach has the advantage that it gives enhanced robustness to poor quality position measurements. For flexible rotors, stabilization with large axial separation of position sensors and bearing locations can be easily achieved by utilizing collocated rotor-embedded accelerometers. The approach also offers improved robustness to measurement noise, position sensor run-out error and other forms of physical contamination or damage. Through analysis and simulation, important physical effects on vibration control performance are identified and further considered within the design methodology.
BibTeX:
@inproceedings{ISMB14_86,
  author = {Matthew Cole and Samuel Jimenez and Patrick Keogh},
  title = {Feedback Control of a Magnetic Bearing Using Fusion of Rotor Acceleration and Position Measurements},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_86.pdf}
}
2014 Onuma, H. and Masuzawa, T. Evaluation of Magnetic Suspension Characteristics and Levitation Performance of a Centrifugal Blood Pump Using Radial Type Self-Bearing Motor Proceedings of ISMB14  
Abstract: Magnetic levitation technology is applied for durability enhancement of artificial hearts. A centrifugal blood pump using a self-bearing motor was previously developed for use as an implantable artificial heart. Rotors of three types which are different of magnetic suspension characteristics were fabricated. The magnetic suspension characteristics, the levitation and the pump performances of the Maglev pump were examined. If the negative spring force in the radial direction was weak, the restoring force in the axial direction and the restoring torque of the inclination were not always weak. It is possible to improve the motor performance by increasing the flux density of permanent magnet, even if the air gap is increased. It revealed that the levitation performance does not influence the pump performance. And then, it is possible to improve the levitation performance by reducing the negative spring force and improving the passive stability ability.
BibTeX:
@inproceedings{ISMB14_87,
  author = {Hiroyuki Onuma and Toru Masuzawa},
  title = {Evaluation of Magnetic Suspension Characteristics and Levitation Performance of a Centrifugal Blood Pump Using Radial Type Self-Bearing Motor},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_87.pdf}
}
2014 Fleischer, E. and Hofmann, W. Linear and Nonlinear Control of a Three Pole Combined Active Magnetic Bearing - a Comparison Proceedings of ISMB14  
Abstract: This paper analyses a linear and a nonlinear control strategy for a 5-axis magnetic suspension system built with two three pole combined bearings. In these soft magnetic composites (SMC) are used as iron core material to carry the required threedimensional flux distribution. While the linear approach is designed around the CLARKE-Transformation to stabilize the bearing, the nonlinear one is based on feedback linearization to achieve a stable system even in the case of minimal bias flux. The paper outlines the control strategies and the controller design. Both schemes are compared regarding tracking behavior, decoupling performance and stability margin based on experimental results in the time and frequency domain.
BibTeX:
@inproceedings{ISMB14_88,
  author = {Erik Fleischer and Wilfried Hofmann},
  title = {Linear and Nonlinear Control of a Three Pole Combined Active Magnetic Bearing - a Comparison},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_88.pdf}
}
2014 Wang, X., Liu, Q., Hu, Y., Chen, H. and Geng, Q. Research on Redundancy of Weak Coupling Radial Magnetic Bearing Proceedings of ISMB14  
Abstract: The weak coupling radial magnetic bearing structure and force balance compensation has been proposed in this paper. The force balance compensation of weak coupling radial magnetic bearing is simulated and comparison with bias current linearization. The research shows the force balance compensation can provide bigger electromagnetic force, the process of solving compensation matrix is simple, and the compensation current is more uniform. Meanwhile, The experimental results verify the feasibility of weak coupling radial magnetic bearing with redundant structure and force balance compensation.
BibTeX:
@inproceedings{ISMB14_89,
  author = {Xiaoguang Wang and Qian Liu and Yefa Hu and Haohui Chen and Qingling Geng},
  title = {Research on Redundancy of Weak Coupling Radial Magnetic Bearing},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_89.pdf}
}
2014 Wang, J. and Binder, A. Position Estimation for Self-Sensing Magnetic Bearings Based on Double Detection of Current Slopes Proceedings of ISMB14  
Abstract: This paper introduces a new approach to estimate the rotor position of self-sensing magnetic bearings, which works on detecting the current slopes during both positive and negative voltage switching of PWM amplifiers. The position is estimated using the current slopes straightforward. The consideration of double current slopes shows advantages concerning the reduction of the influences of the coil resistance and the induced voltage due to the rotor movement. The current slope is calculated by multiple current sampling, therefore, no additional hardware is needed for the current slope measurement. Experimental results verified the proposed approach.
BibTeX:
@inproceedings{ISMB14_9,
  author = {Jinou Wang and Andreas Binder},
  title = {Position Estimation for Self-Sensing Magnetic Bearings Based on Double Detection of Current Slopes},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_9.pdf}
}
2014 Richter, M., Schaede, H. and Rinderknecht, S. Investigations on the "Direct Digital Inductance Estimation" - Concept for Self-Sensing AMBs Under Influence of Eddy Currents Proceedings of ISMB14  
Abstract: This article states the challenges connected with eddy-currents by use of the direct digital inductance estimation (DDIE) concept for self-sensing active magnetic bearings. Starting with a short introduction to the estimation algorithm, the negative influences of eddy currents on the position estimation are described step by step. Such influences are an increasing position noise as well as an interval and duty cycle dependent position error. The article closes with an outlook on additional investigations to further separate, quantify, and reduce the associated position error in order to extend the performance of the DDIE-concept.
BibTeX:
@inproceedings{ISMB14_90,
  author = {Michael Richter and Hendrik Schaede and Stephan Rinderknecht},
  title = {Investigations on the "Direct Digital Inductance Estimation" - Concept for Self-Sensing AMBs Under Influence of Eddy Currents},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_90.pdf}
}
2014 Lundin, J., Kamf, T., Abrahamsson, J., de Santiago, J., Hedlund, M. and Bernhoff, H. High Speed Flywheels for Vehicular Applications Proceedings of ISMB14  
Abstract: This article analyzes two business cases using flywheels in vehicles. Firstly, a diesel based car ferry, in Gothenburg, performing 102 5 minute long journeys per day. Secondly, a diesel based city bus. A theoretical analysis of the benefits, technical and economical, of electrifying these vehicles using flywheels is performed. As basis for the analysis is a constructed high-speed flywheel, designed to store up to 870Wh at a rotational speed of 30 000 rpm. The rotor of the flywheel is constructed from a permanent magnet machine surrounded by a shell of composite material. The flywheel is optimized for low loss as well as low cost. The economical analysis of the two business cases show great potential for cost reduction by either utilizing a flywheel as temporary energy storage for capturing regenerative braking energy or replacing the diesel generator completely as main energy storage. The main material cost of the constructed flywheel pertains to the position sensors and the permanent magnet material used in the magnetic bearing.
BibTeX:
@inproceedings{ISMB14_91,
  author = {Johan Lundin and Tobias Kamf and Johan Abrahamsson and Juan de Santiago and Magnus Hedlund and Hans Bernhoff},
  title = {High Speed Flywheels for Vehicular Applications},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_91.pdf}
}
2014 Mach, F., Karban, P. and Dolezel, I. Design of Novel Bearing-Less Electromagnetic Actuator in Valve Operation Proceedings of ISMB14  
Abstract: A new bistable electromagnetic actuator is designed and modelled. The actuator with a magnetically moved plunger represents the main part of a valve intended for control of flow of electrically non-conductive liquids. Presented is the basic concept of the valve together with its mathematical model that is solved numerically by the code Agros2D developed by the authors. The aim of the work is to verify the functionality of the device and find its basic operation characteristics.
BibTeX:
@inproceedings{ISMB14_92,
  author = {Frantisek Mach and Pavel Karban and Ivo Dolezel},
  title = {Design of Novel Bearing-Less Electromagnetic Actuator in Valve Operation},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_92.pdf}
}
2014 Bonfitto, A., Cabrera, L.D.S. and Tonoli, A. Active Magnetic Bearings with Position and Flux Observer Proceedings of ISMB14  
Abstract: Standard Active Magnetic Bearings are controlled using a current reference and the measured or observed current as state variable in the state space controller. Nevertheless since this approach selects the current as the state expressing the behavior of the magnetic bearing, several disadvantages occur. Indeed it is well known that this method leads to an inherent nonlinear relation between the generated force, the current and the air gap. This paper presents the modeling approach, the control design and the experimental validation of a strategy based on the combined observation of position and flux. The technique is designed and tested on a one-degree of freedom mechanical oscillator actuated by a couple of opposite electromagnets.
BibTeX:
@inproceedings{ISMB14_93,
  author = {Angelo Bonfitto and Lester Daniel Suarez Cabrera and Andrea Tonoli},
  title = {Active Magnetic Bearings with Position and Flux Observer},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_93.pdf}
}
2014 Schaede, H., Richter, M., Quurck, L. and Rinderknecht, S. Losses in an Outer-Rotor-Type Kinetic-Energy-Storage-System in Active Magnetic Bearings Proceedings of ISMB14  
Abstract: This paper starts with a general description of the losses and the classification of the loss components in kinetic energy storage systems. Based on the design of an outer-rotor-type kinetic energy storage system an analytical loss model is presented. It considers the conversion losses and the drag losses of the electric drive, the drag losses of the homopolar active magnetic bearings and the gas friction losses, as well as the constant losses such as caused by the bias magnetization of the active magnetic bearings. In detail a new approach for the analytical calculation of the drag losses of the homopolar active magnetic bearings is presented, taking the eddy current and hysteresis losses as well as the penetration depth of the magnetic field into the rotor in account. The paper ends with the presentation of a developed measurement method for the experimental determination of the loss map of kinetic energy storage systems. It enables for the isolation of the drag loss components of the drive system, the magnetic bearings and the gas friction losses.
BibTeX:
@inproceedings{ISMB14_94,
  author = {Hendrik Schaede and Michael Richter and Lukas Quurck and Stephan Rinderknecht},
  title = {Losses in an Outer-Rotor-Type Kinetic-Energy-Storage-System in Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_94.pdf}
}
2014 Whitlow, Z., Fittro, R. and Knospe, C. Segmented Magnetic Thrust Bearings: Analytic Models and Predictions of Significant Improvement in Dynamic Performance Proceedings of ISMB14  
Abstract: Non-laminated magnetic thrust bearings typically exhibit reduced dynamic performance due to eddy currents compared to laminated bearings. Segmented stators have been introduced to increase actuator performance by disrupting eddy current paths in the same manner as laminations in radial magnetic bearings. However, due to manufacturing limitations thrust bearing stators cannot be easily segmented to the extent that they would be considered fully laminated. Therefore, eddy currents continue to affect the dynamic performance significantly. Since analytic models of segmented stators do not presently exist the bearing design process requires the use of finite element analysis (FEA) and experimentation. Here we show, using finite element analysis, that a small number of cuts dramatically improves bandwidth of non-laminated magnetic actuators, validating the segmented design strategy. In addition, existing analytic models of non-laminated magnetic bearings are adapted to a segmented geometry and validated via FEA. Close agreement shows that the analytic model, rather than time consuming FEA, may be used in the design process.
BibTeX:
@inproceedings{ISMB14_95,
  author = {Zackary Whitlow and Roger Fittro and Carl Knospe},
  title = {Segmented Magnetic Thrust Bearings: Analytic Models and Predictions of Significant Improvement in Dynamic Performance},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_95.pdf}
}
2014 Li, P., Sahinkaya, N. and Keogh, P. Active Touchdown Bearing Control for Recovery of Contact-Free Rotor Levitation in AMB Systems Proceedings of ISMB14  
Abstract: Control strategies for rotor displacements and transmitted forces in active magnetic bearing (AMB) systems are generally well-developed when the rotor is in contact-free levitation. In such a condition, the rotor/AMB system, the plant to be controlled, is well-defined to use for controller design. However, transient overload conditions or large scale disturbances may cause the rotor to make contact with one or more touchdown bearings (TDBs). The ensuing dynamic response is an effective change to the contact-free plant, which may cause an AMB controller to apply inappropriate forces, causing persistent contact, or even inducing system instability. It is therefore beneficial to restore contact-free levitation as quickly as possible in order that normal operation may resume. This would minimise outage time and also minimise high levels of potentially damaging contact that may be experienced by the TDBs. In this paper, the use of an active TDB is considered for the restoration of contact-free levitation. The contact problem is demonstrated in simulation and also through appropriate control applied in an experimental system. In this system, TDB motion is activated by piezoelectric stack actuators.
BibTeX:
@inproceedings{ISMB14_96,
  author = {Peichao Li and Necip Sahinkaya and Patrick Keogh},
  title = {Active Touchdown Bearing Control for Recovery of Contact-Free Rotor Levitation in AMB Systems},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_96.pdf}
}
2014 Cui, Q., Sandtner, J. and Bleuler, H. Whirl Imposer --- Proposal for a Novel Passive Magnetic Rotor Bearing System Proceedings of ISMB14  
Abstract: Passive magnetic bearing systems are enticing in applications where low stiffness is acceptable, but where cost, life-time, power consumption and reliability are critical. This article investigates a new proposal for stabilization of permanent magnet (i.e. passive) bearing systems based on rotor precession. There will be a minimal and a maximal rotational speed for stable contact-free levitation. The feasibility of this new stabilization scheme is investigated with the help of realistic numerical data, a demonstration system is currently in planning.
BibTeX:
@inproceedings{ISMB14_97,
  author = {Qingwen Cui and Jan Sandtner and Hannes Bleuler},
  title = {Whirl Imposer --- Proposal for a Novel Passive Magnetic Rotor Bearing System},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_97.pdf}
}
2014 Collins, T., Masala, A., Shultz, R. and Guo, Z. Numerical and Experimental Results of Auxiliary Bearings Testing on a High Speed Test Rig Proceedings of ISMB14  
Abstract: A test stand including a rotor and active magnetic bearing system, located at Waukesha Magnetic Bearing premises was utilized in 2013 to validate a new auxiliary bearing design. This paper provides an overview of the preparatory activities and an insight on the numerical and experimental results obtained during the testing campaign.
BibTeX:
@inproceedings{ISMB14_98,
  author = {Tim Collins and Andrea Masala and Richard Shultz and Zenglin Guo},
  title = {Numerical and Experimental Results of Auxiliary Bearings Testing on a High Speed Test Rig},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_98.pdf}
}
2014 Recheis, M. Increasing Bearing Life-Time of Mobile Flywheels by Using Bearing-Less Drive Methods Proceedings of ISMB14  
Abstract: Fully electric and hybrid electric power trains enable reuse of braking energy. This decreases the amount of lost energy dramatically, especially for discontinuous operation. Good examples are urban traffic, public transportation or delivery services. Mobile flywheels provide an excellent potential for the emerging market of electrified power trains, but they are currently only used in a few applications such as motor sports (Formula 1, Le Mans, GT3 car racing). To enable a wider use in personal or public transportation, the life-span of the flywheel’s bearings have to be increased significantly. This paper presents an alternative approach to extend the life-span of the rolling element bearings by using bearing-less drive methods.
BibTeX:
@inproceedings{ISMB14_99,
  author = {Manes Recheis},
  title = {Increasing Bearing Life-Time of Mobile Flywheels by Using Bearing-Less Drive Methods},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_99.pdf}
}
2014 Mushi, S. and Allaire, P. Control of a Flexible Rotor AMB Compressor Test Rig with Aerodynamic Cross Coupling Proceedings of ISMB14  
Abstract: Many industrial companies are adopting magnetic bearings for high speed compressors at this time. A flexible rotor test rig of approximately 1.2 m in length was developed with four active magnetic radial bearings. It was employed to evaluate the control of destabilizing aerodynamic cross coupling stiffness Q in the center of the machine. The two end AMBs were used for support and one center AMB used to apply the cross coupled stiffness corresponding to a typical location of gas seal cross coupled stiffness sources. The fourth AMB was employed as a system exciter. Unfortunately for the compressor manufacturer and the end user, often the magnitude of the cross coupled stiffness changes with various compressor operating conditions. The test rig shaft operated up to about 18,000 rpm, through the first bending critical speed which was at approximately 14,000 rpm. m-synthesis control was used to achieve highly effective control and low vibration response with the selection of an averaged value of cross coupled stiffness Q and a set of useful system uncertainty weighting functions when the controller does not have exact advance notice of the cross coupling stiffness amplitude. Details of the application of the mu synthesis controller implementation are presented. A physical approach to modeling the Q uncertainty involved selecting an expected nominal value of the real part of the first rotor system eigenvalue for the rotor first bending mode with an expected range of uncertainly above and below that value. Then suitable weighting functions were developed for the mu synthesis controller design. The measured sensitivity function was below 3 at 7,000 rpm when the rotor was subjected to high cross coupled stiffness at the center.
BibTeX:
@inproceedings{ISMB14_key01,
  author = {Simon Mushi and Paul Allaire},
  title = {Control of a Flexible Rotor AMB Compressor Test Rig with Aerodynamic Cross Coupling},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_key01.pdf}
}
2014 Bleuler, H. Overview on Various Types of AMBs & their Respective Potential for Applications Proceedings of ISMB14  
Abstract: Many different types of magnetic bearings are known since a long time: “Active” and “passive”, “electrodynamic”, “electromagnetic”, “hybrid” etc. Certain types have found many applications and others none. A recent successful realization of a complex system (a momentum reaction sphere) based on a Lorentz-force type of bearing will be presented in more detail and the potential of as yet unexploited types of magnetic bearings will be briefly discussed.
BibTeX:
@inproceedings{ISMB14_key02,
  author = {Hannes Bleuler},
  title = {Overview on Various Types of AMBs & their Respective Potential for Applications},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_key02.pdf}
}
2014 Kroll, M. Electrical drive systems with active magnetic bearings in industrial applications - possibilities and challenges Proceedings of ISMB14  
Abstract: This article describes the use of active magnetic bearings in an electrical drive system and how performance, reliability and availability can be increased significantly based on an application example. It is important to know about the strong interaction between the different system components to get the best technical results, as well as considering production related aspects.
BibTeX:
@inproceedings{ISMB14_key03,
  author = {Matthias Kroll},
  title = {Electrical drive systems with active magnetic bearings in industrial applications - possibilities and challenges},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_key03.pdf}
}
2014 Sloupensky, J. Magnetic Bearings: Application to High Speed Textile Processing Proceedings of ISMB14  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB14_key04,
  author = {Jiri Sloupensky},
  title = {Magnetic Bearings: Application to High Speed Textile Processing},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_key04.pdf}
}
2014 Swann, M. Industrialisation Trends for Active Magnetic Bearings in the Turbomachinery Industry Proceedings of ISMB14  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB14_key05,
  author = {Mike Swann},
  title = {Industrialisation Trends for Active Magnetic Bearings in the Turbomachinery Industry},
  booktitle = {Proceedings of ISMB14},
  year = {2014},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb14/ismb14_submission_key05.pdf}
}
2013 Bulic, N., Dirnberger, P. and Silber, S. New Sensor Design for Rotor Displacement Measurement Based on the Coupled Oscillators Theory Proceedings of BWMB2013  
Abstract: Measurement of rotor position in bearingless motors and bearingless systems is of essence for proper operation. Insufficient resolution, sensor insensitivity and low sampling rate in measurement process leads unstable levitation and in worst case to the collision of rotor and stator which could end with motor destruction. Paper presents new concept for rotor position measurement based on Eddy current principle and Coupled oscillators theory in order to get accurate rotor position information. New concept is based on injection locking phenomena between coupled oscillators. Opposite pair of sensing oscillators are electrically coupled via resistor. In injection locking conditions phase shift between coupled oscillators is proportional to rotor movement. Phase shift was measured with Time to Digital Converter (TDC) and information is passed to Digital Signal Processor DSP over SPI communication link. DSP calculates the rotor position which is passed to power electronic circuit for rotor position control.
BibTeX:
@inproceedings{BWMB2013_1,
  author = {Neven Bulic and Peter Dirnberger and Sigfried Silber},
  title = {New Sensor Design for Rotor Displacement Measurement Based on the Coupled Oscillators Theory},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_1.pdf}
}
2013 Filatov, A.V. and Hawkins, L.A. Novel Combination Radial/Axial Homopolar Active Magnetic Bearing Proceedings of BWMB2013  
Abstract: A novel combination radial/axial homopolar permanent-magnet-biased electromagnetic actuator for application in active magnetic bearings is proposed. The design combines the best features of the earlier solutions: shorter axial length, lower part count, lower aerodynamic drag, lower negative stiffness and lower cost typical for combination bearings along with better axial bandwidth typically demonstrated in arrangements of separate radial and axial bearings. Furthermore, for most machines, the actuator topology leads to rotor construction that results in a higher first bending mode frequency than previous designs.
BibTeX:
@inproceedings{BWMB2013_12,
  author = {Alexei V. Filatov and Lawrence A. Hawkins},
  title = {Novel Combination Radial/Axial Homopolar Active Magnetic Bearing},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_12.pdf}
}
2013 de Paiva, J.A., Salazar, A.O. and Maitelli, A.L. Review of Control Strategies and Model Estimation Techniques applied to Bearingless Induction Machine with Divided Winding Proceedings of BWMB2013  
Abstract: The bearingless induction machines exhibit significant nonlinearities, creating the need for implementation of control systems that combine the classic control techniques with modern model observers. Aiming to contribute to the development of new systems, this paper presents an overview of the main control and estimation strategies implemented in laboratory using the induction bearingless machines with divided winding, highlighting the advances and difficulties arising from these type of systems.
BibTeX:
@inproceedings{BWMB2013_14,
  author = {Jose A. de Paiva and Andres O. Salazar and Andre L. Maitelli},
  title = {Review of Control Strategies and Model Estimation Techniques applied to Bearingless Induction Machine with Divided Winding},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_14.pdf}
}
2013 Rudolph, J., Werner, R. and Maximow, I. Measurement of the Rotor Position of an Active Magnetic Bearing Using Interpolar Stray Flux Proceedings of BWMB2013  
Abstract: The very most active magnetic bearings need somehow natured shaft measurement systems. To reduce the significant cost which are caused by the measurement systems a HALL-principle based system is proposed where low budget industrial standard sensors are applied. Contrary to other approaches the HALL-sensors are integrated between the bearing poles instead the air gap. Thus the use of low budget sensors is enabled.
BibTeX:
@inproceedings{BWMB2013_15,
  author = {Johannes Rudolph and Ralf Werner and Ivo Maximow},
  title = {Measurement of the Rotor Position of an Active Magnetic Bearing Using Interpolar Stray Flux},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_15.pdf}
}
2013 Lopes, J.S.B., dos S. Junior, L.P., de Paiva, J.A., Salazar, A.O. and Maitelli, A.L. Adaptative Neuro-Fuzzy Inference System for Estimation of Rotor Flux of a Bearingless Induction Motor applied to Speed Control Proceedings of BWMB2013  
Abstract: This study presents the problem of rotor flux orientation control of bearingless induction motor. The key of this solution is the estimation of rotor flux. This work applied an inference system using fuzzy logic and the neural networks with the MATLAB®. The Adaptive Neuro-Fuzzy Inference System (ANFIS) which is based in an input-output model is used to tune the membership functions in fuzzy system. ANFIS along with the back propagation learning algorithm was applied to estimate the rotor flux and the magnetization current for the purpose of identifying bearingless induction motor angular speed. ANFIS aims at compensating possible parametric variations of the machine caused by agents such as temperature or nucleus saturation. The simulated results showed good performance. The inference proposed system will be implemented in DSP’s.
BibTeX:
@inproceedings{BWMB2013_21,
  author = {Jose S. B. Lopes and Luciano P. dos S. Junior and Jose A. de Paiva and Andres O. Salazar and Andre L. Maitelli},
  title = {Adaptative Neuro-Fuzzy Inference System for Estimation of Rotor Flux of a Bearingless Induction Motor applied to Speed Control},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_21.pdf}
}
2013 Rodriguez, E. and Stephan, R. Radial and axial forces of a passive magnetic bearing Proceedings of BWMB2013  
Abstract: Active magnetic bearings require sensors, actuators and controllers, guaranteeing a specified dynamic behavior. Passive Magnetic Bearings, on the other hand, use simpler hardware, but do not have any dynamic control, therefore demanding improvements in the design and optimization process. This paper presents a contribution to the optimization process and dynamic behavior of PMB with permanent magnets. A single layer and two double layer configurations will be analyzed. Simulation and experimental results of static forces will be compared. Finally, experimental dynamic tests will be carried out.
BibTeX:
@inproceedings{BWMB2013_22,
  author = {Elkin Rodriguez and Richard Stephan},
  title = {Radial and axial forces of a passive magnetic bearing},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_22.pdf}
}
2013 Lorenz, F. and Werner, R. Comparison of magnetic bearings and hybrid roller bearings in a mobile flywheel energy storage Proceedings of BWMB2013  
Abstract: The comparison of active magnetic bearings and hybrid ceramic roller bearings regarding their application in a mobile flywheel energy storage is discussed in this paper. The consequences of using the two mentioned bearing types are presented concerning dynamic behavior, load capabilities, constructive parameters and reliability. To achieve a design guidance which bearing type to use two flywheel designs with the same power and capacity but different bearing concepts were simulated in a simplified drive cycle to show their different characteristics.
BibTeX:
@inproceedings{BWMB2013_23,
  author = {Fabian Lorenz and Ralf Werner},
  title = {Comparison of magnetic bearings and hybrid roller bearings in a mobile flywheel energy storage},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_23.pdf}
}
2013 Gruber, W., Bauer, W., Radman, K., Amrhein, W. and Schoeb, R.T. Considerations Regarding Bearingless Flux-Switching Slice Motors Proceedings of BWMB2013  
Abstract: The bearingless flux-switching slice motor is a compact magnetically levitated drive featuring no permanent magnets in the rotor. In this article the working principle of this novel bearingless motor topology is studied and its operational behavior is evaluated using performance factors for bearing and torque generation. Three dimensional finite element simulations are performed to optimize a promising motor variant, showing encouraging results, that will be verified in the future with the help of a prototype.
BibTeX:
@inproceedings{BWMB2013_27,
  author = {W. Gruber and W. Bauer and K. Radman and W. Amrhein and R. T. Schoeb},
  title = {Considerations Regarding Bearingless Flux-Switching Slice Motors},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_27.pdf}
}
2013 Hedlund, M., Abrahamsson, J., Perez-Loya, J.J., Lundin, J. and Bernhoff, H. Passive Axial Thrust Bearing for a Flywheel Energy Storage System Proceedings of BWMB2013  
Abstract: Two types of passive magnetic lift bearings are evaluated in terms of lift force and eddy current losses. Two sources of eddy currents are analyzed with help of the finite element method, firstly losses due to non-radial magnetization of magnets, and secondly losses due to variations in remanence. Magnets placed are placed in a Halbach array on the rotor and ring-magnets are placed on the stator. Denoted semi-segmented bearings, these produce low losses in the rotor, thus limiting the need of heat transport during vacuum operation. Experimental results of lift force are presented, together with simulations results. The losses were found to be in the order of 9 W at a rotational speed of 30 000 rpm while producing 900 N of thrust. The FEM-problem is solved with time-dependent terms, and is compared with a stationary approximation.
BibTeX:
@inproceedings{BWMB2013_3,
  author = {Magnus Hedlund and Johan Abrahamsson and Jesus Jose Perez-Loya and Johan Lundin and Hans Bernhoff},
  title = {Passive Axial Thrust Bearing for a Flywheel Energy Storage System},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_3.pdf}
}
2013 Ferreira, H.P., de M. Endalecio, A.D. and Stephan, R.M. Development of Levitation Experiments for Teaching Purposes Proceedings of BWMB2013  
Abstract: The objective of this paper is to present two magnetic levitation experiments, which give a first didactic approach to the concepts necessary to understand magnetic bearings. On the first experiment, an electrodynamic levitation system with alternating current, capable of levitating metallic rings will be presented. On the second experiment, an electromagnetic levitation system, using a Hall effect sensor to measure the levitated object position – a ferromagnetic sphere combined with permanent magnets – will be described. These laboratory rigs demonstrate the importance of simulation tools and experimental work on the verification of theoretical concepts learned in Electrical/Electronic Engineering classes.
BibTeX:
@inproceedings{BWMB2013_31,
  author = {H. P. Ferreira and A. D. de M. Endalecio and R. M. Stephan},
  title = {Development of Levitation Experiments for Teaching Purposes},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_31.pdf}
}
2013 Pesch, A.H. and Sawicki, J.T. Experimentally Based Prediction of Machining Chatter Characteristics for AMB Spindle Proceedings of BWMB2013  
Abstract: In a previous work, a high-speed spindle was made to attenuate machining chatter through application of robust control to AMB supports. In the present work, tooltip compliance of the levitated system is experimentally measured by impulse testing. Using the compliance measurement, the stability lobe diagram and critical chatter frequency diagram are calculated by means of Nyquist stability theory applied to the cutting force feedback loop. This experimentally based stability lobe diagram quantifies the improvement of machining stability when using the chatter avoiding AMB controller. The chatter frequency diagram is helpful in identifying the onset of chatter and posteriori AMB controller tuning. Also from the compliance data, critical phase shift between the inner and outer cut modulus is calculated for a range of machining speeds. The critical phase shift shows the amount of regenerative effect needed to cause machining chatter at each speed and confirms the advantageous machining speeds found in the stability lobe diagram.
BibTeX:
@inproceedings{BWMB2013_34,
  author = {Alexander H. Pesch and Jerzy T. Sawicki},
  title = {Experimentally Based Prediction of Machining Chatter Characteristics for AMB Spindle},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_34.pdf}
}
2013 David, D., Santisteban, J. and Gomes, A.D.N. Interconnected Four Poles Magnetic Bearing Proceedings of BWMB2013  
Abstract: This article analyses the adaptation of the split-wind bearingless motors structure for magnetic bearings. Preliminary theoretical results predict that a greater equivalent stiffness could be achieved when compared to the values associated with the active magnetic bearing conception traditionally described in the literature.
BibTeX:
@inproceedings{BWMB2013_36,
  author = {D.F.B. David and J.A. Santisteban and A.C. Del Nero Gomes},
  title = {Interconnected Four Poles Magnetic Bearing},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_36.pdf}
}
2013 Mizuno, T., Yoneno, Y., Ishino, Y. and Takasaki, M. Proposal of Flux-Path Control Magnetic Suspension using Flux Concentration Proceedings of BWMB2013  
Abstract: The concept of flux concentration was applied to the flux-path control magnetic suspension to increase suspension force. In the proposed system, control plates made of permanent magnet were used instead of ferromagnetic control plates in the conventional flux-interrupted type. The magnets were arranged to concentrate the flux from the magnetic source to the floator. Such effects were confirmed by magnetic field analysis. An experimental study shows that the suspension force achieved by the fluxconcentrated type was approximately 2.5 times that achieved by the flux-interrupted type with the same size. In addition, contactless suspension was achieved by applying PD control in the flux-concentrated type suspension system.
BibTeX:
@inproceedings{BWMB2013_4,
  author = {Takeshi Mizuno and Yuuki Yoneno and Yuji Ishino and Masaya Takasaki},
  title = {Proposal of Flux-Path Control Magnetic Suspension using Flux Concentration},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_4.pdf}
}
2013 Horikawa, O., Yamamoto, R.I. and da Silva, I. Development of Single Axis Controlled Attraction Type Magnetic Bearing and its Application in Ventricular Assist Device Proceedings of BWMB2013  
Abstract: Aiming the development of an implantable Ventricular Assist Device – VAD, or an artificial heart, a joint project was started in 2007, involving the Escola Politécnica of São Paulo University (EPUSP) and the Dante Pazzanese of Cardiology (IDPC). One of objectives of the project is the development of a VAD with a rotor levitated by a magnetic bearing. Here, a magnetic bearing proposed by authors, called as EPUSP bearing, is elected mainly because of its simplicity. This work presents the entire development work. One of most important work is related with the mitigation of a topology of the EPUSP bearing that enables a robust levitation, enough for supporting the rotor of a VAD. Moreover some complementary studies are developed so as to execute the Zero Power control in the EPUSP bearing, identify the best way of driving the rotor supported by the EPUSP bearing and finally, use the Hall sensor in the measurement of the rotor position in the EPUSP bearing.
BibTeX:
@inproceedings{BWMB2013_5,
  author = {Oswaldo Horikawa and Rogerio I. Yamamoto and Isaias da Silva},
  title = {Development of Single Axis Controlled Attraction Type Magnetic Bearing and its Application in Ventricular Assist Device},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_5.pdf}
}
2013 Jayawant, R. and Davies, N. Integration of Signal Processing Capability in an AMB Controller to Support Remote and Automated Commissioning Proceedings of BWMB2013  
Abstract: One major limitation to the wide adoption of active magnetic bearings (AMBs) in industry is the time required for commissioning and tuning. In this paper we will report how integration of signal processing capability (especially multi-channel transfer function measurements) within the AMB controller can reduce total commissioning time and especially, the time required on site by a highly skilled AMB specialist. We also show how PC based automatic commissioning tools make it possible for OEM and end user engineers to commission, tune and maintain AMB machines with only occasional remote support from the AMB vendor and without specialist rotor-dynamic test equipment. Secondary benefits from this approach include increased traceability and repeatability of the tuning process. The automated commissioning is based on MATLAB scripts and data analysis capabilities. This runs on a separate PC which (via the controller network interface) configures the measurements to be made by the AMB controller. Analysis of the resulting measurements allows automatic modification of controller parameters. These scripts cover several control loops and estimators within the AMB controller including current, flux and position servo control. The robustness and vibration performance are used to assess the resulting control loop. This is based around a concept of dynamic templates which correlate to acceptance criteria according to ISO 14839-2 and ISO 14839-3. Results from running the automated commissioning process on a high speed test rig are presented. The results show that the dynamic template model provides good control performance with rapid tuning time. This technology has the potential for the development of sophisticated diagnostic routines which could be activated in the event of anomalous readings, and this further future work is briefly described.
BibTeX:
@inproceedings{BWMB2013_6,
  author = {Richard Jayawant and Nigel Davies},
  title = {Integration of Signal Processing Capability in an AMB Controller to Support Remote and Automated Commissioning},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_6.pdf}
}
2013 Jayawant, R. and Dabbs, S. A Novel Digital Circuit for Position Sensor De-modulation Using Advanced FPGA, Including Field Experience with a 1.45MW Motor Driven Compressor Proceedings of BWMB2013  
Abstract: This paper describes a novel demodulation circuit which has been developed for use with inductive position sensors for Active Magnetic Bearing applications. The circuit is designed to operate with conventional bridge type inductive position sensors. This circuit is novel in that the implementation is fully digital and uses a mixture of FPGA and DSP to ensure noise immune phase sensitive de-modulation. We present the architecture and implementation of the new circuit. The techniques to perform the phase sensitive de-modulation are described, including the techniques necessary to handle the phase shifts due to cable capacitance. In conventional analogue based systems these phase shifts are compensated by field changes to component values. The experience of using this sensor on a 1.5MW motor driven hydrogen compressor is described. We present the results and experiences of commissioning the machine. The noise levels recorded during testing, and the overall response of the machine both whilst levitated (non-rotating) and during operation are included. We finish with a comparison of the two methodologies; the precision analogue circuitry versus the digital along with our conclusions.
BibTeX:
@inproceedings{BWMB2013_7,
  author = {Richard Jayawant and Steve Dabbs},
  title = {A Novel Digital Circuit for Position Sensor De-modulation Using Advanced FPGA, Including Field Experience with a 1.45MW Motor Driven Compressor},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_7.pdf}
}
2013 Kumar, P. and Jayawant, R. Commissioning Experience with Dynamic Termination of Transmission Line Effects in an Extended Magnet Cable Application Proceedings of BWMB2013  
Abstract: Active magnetic bearing controllers generate current and voltage commands in response to axial and radial forces acting on rotating shaft. The subsystems that respond to these commands are known as power amplifiers. Due to advancements in power electronics and rapid industrial trend towards higher efficiency, compactness and lower cost, recent AMB’s utilize switched mode PWM power amplifiers which regulate current in magnets by varying the ratio of on duration of switching device to switching period. With increasing no of AMB installations in hazardous areas for e.g. volatile gas compressors, it is imperative to provide a safe separation distance between the bearing and the control system itself. Transmission line effects can result in power cables connecting the PWM power amplifier to the bearing in such installations. These effects give rise to voltage and current reflections due to a mismatch of source, line and load impedance at high switching frequencies. They can cause insulation failures, overvoltage, ringing and improper operation of parts subjected to these voltages and currents. A dynamic termination circuit was developed at Waukesha Magnetic Bearings to terminate these reflections on a strategic basis according to instantaneous PWM pulse amplitude and return most of the reflected energy to the DC link power supply. This paper discusses actual results seen during commissioning on site in which an AMB system was successfully employed to suspend a volatile gas compressor rotor shaft by mitigating transmission line effects in the power cables. It is also shown that this circuit can improve dynamic performance of PWM power amplifier and meet requirements of industrial AMB’s in hazardous area applications.
BibTeX:
@inproceedings{BWMB2013_8,
  author = {Praveen Kumar and Richard Jayawant},
  title = {Commissioning Experience with Dynamic Termination of Transmission Line Effects in an Extended Magnet Cable Application},
  booktitle = {Proceedings of BWMB2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/bwmb2013/bwmb2013_submission_8.pdf}
}
2013 Schmied, J. and Kosenkov, A. Practical Controller Design for Rotors on Magnetic Bearings by Means of an Efficient Simulation Tool Proceedings of SIRM2013  
Abstract: This paper describes in detail by means of a realistic example and an efficient simulation tool the whole procedure of the magnetic bearing controller design. In a first step the suitability of the rotor is assessed. The objectives for the actual controller design to ensure a robust system, which is suited for the application, are then explained. In a first step of the design a controller structure, which is a series of proven filters with stable poles, is defined. The strategy to select the filters is determined by the rotor properties and the hardware characteristics of the bearing. The parameters of the controller are then optimized to fulfil the objectives. The optimization can be automated by the definition of suited goals, which are closely related to the objectives. Finally the performance of the resulting rotor bearing system is assessed.
BibTeX:
@inproceedings{SIRM2013_1,
  author = {Joachim Schmied and Alexander Kosenkov},
  title = {Practical Controller Design for Rotors on Magnetic Bearings by Means of an Efficient Simulation Tool},
  booktitle = {Proceedings of SIRM2013},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/sirm2013/sirm2013_submission_1.pdf}
}
2013 Grund, C. and Rotenbach, T. Untersuchungen zu einer magnetgelagerten Industriedampfurbine Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Der Einsatz aktiver Magnetlager an Turboma-schinen in Kraftwerken reduziert die Brandmasse durch den Wegfall des Ölkreislaufes zur Lagerschmierung gegenüber konventionell gelagerten Turbomaschinen erheblich und ver-ringert folglich das Gefährdungspotential. Die magnetlagerspezifisch geringe Lagerreibung führt zudem zu einer Erhöhung des Wirkungsgrades und zu einer Senkung des Wartungs- und Instandhaltungsaufwandes. Die Auswertung der inhärenten Signale der Magnetlagerung – Wellenlagen und Lagerströme – bietet zusätzliche Möglichkeiten der Überwachung und Diagnose der Magnetlager als auch des Gesamtsystems.Zur Qualifizierung des Einsatzes aktiver Magnetlager an einer Speisepumpenantriebsturbine (SPAT) im Kraftwerk wurde in einem gemeinsamen Projekt zwischen der Siemens AG, der EAAT GmbH Chemnitz und dem IPM der Hochschule Zittau/Görlitz ein Großversuchsstand konzipiert und aufgebaut. Nach der Inbetriebnahme der komplexen Anlage wurden Versuche unter praxisrelevanten Bedingungen durchgeführt. Der Beitrag gibt einen Überblick über die Ver-suchsanlage und stellt die Möglichkeiten der experimentellen Untersuchungen und erste Ergebnisse vor.
BibTeX:
@inproceedings{WMLT9_1,
  author = {C. Grund and T. Rotenbach},
  title = {Untersuchungen zu einer magnetgelagerten Industriedampfurbine },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_1.pdf}
}
2013 Düsterhaupt, S. and Worlitz, F. Komplexe und integrierte Methoden zur Zuverlässigkeitsbewertung berührungsfreier Lager Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Für den Einsatz aktiver Magnetlager in der Energietechnik muss die Zuverlässigkeit des Gesamtsystems nachgewiesen werden. Der Einsatz von Magnetlagerungen in Turbomaschinen, wie sie bspw. Turbinen, Pumpen und Verdichter darstellen, ist durch extreme Prozess- und Umgebungsbedingungen charakterisiert. Fertigungstoleranzen in den Lagerkomponenten und die Beeinflussung durch spezifische Betriebs- und Störszenarien führen zu Parameterdriften, die um die Erwartungswerte einer Nennwertauslegung streuen. Die Folge ist eine arbeitspunkt- und lastabhängige Zuverlässigkeit der Lagerkomponenten. Ein unter Nominalbedingungen funktionsfähiges aktives Magnetlager versagt ggf. aufgrund mechanischer, elektrischer oder magnetischer Parameterdriften. Die Auslegung aktiver Magnetlager soll um die Zuverlässigkeitsanalyse unter Berücksichtigung von Nichtlinearitäten erweitert werden. Dabei werden mit Hilfe geeigneter Methoden im Gegensatz zur diskreten Herangehensweise die spezifischen Lagerparameter unscharf betrachtet. Mit Hilfe der Monte- Carlo-Simulation werden im Rahmen von Simulationen Teilversagenswahrscheinlichkeiten der Komponenten ermittelt und mit Hilfe der Fehlerbaumanalyse zu einer Versagenswahrscheinlichkeit des Gesamtsystems zusammengefasst. Es wird im Auslegungsprozess ermittelt, welche Komponenten des Regelkreises redundant/diversitär ausgeführt werden müssen.
BibTeX:
@inproceedings{WMLT9_10,
  author = {S. Düsterhaupt and F. Worlitz},
  title = {Komplexe und integrierte Methoden zur Zuverlässigkeitsbewertung berührungsfreier Lager },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_10.pdf}
}
2013 Fleischer, E. and Hofmann, W. Elektromechanische Modellierung eines dreipoligen Kombilagers mittels des Lagrange-Formalismus Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Entwickelt wurde ein neuartiges dreipoliges Kombilager und erstmals Pulververbundwerkstoffe (SMC, Soft Magnetic Composite) eingesetzt. Vorgestellt wird ein elektromechanisches Simulationsmodell, das zur Verifikation des Regelsystems dient. Die angewendete Methodik auf Basis des Lagrangeschen Formalismus erlaubt eine systematische Modellierung aktiver Magnetlager als elektromechanischer Energiewandler und ber¨ucksichtigt die R¨uckwirkung der Rotorbewegung auf die Wicklungsstr¨ome, Kreiseleffekte und die magnetische Kopplung der Lagerachsen und Wicklungen. Nach einer Einf¨uhrung in den Lagrangeschen Formalismus wird seine Anwendung auf die neue Lagerstruktur gezeigt und im Experiment nachgewiesen.
BibTeX:
@inproceedings{WMLT9_11,
  author = {E. Fleischer and W. Hofmann},
  title = {Elektromechanische Modellierung eines dreipoligen Kombilagers mittels des Lagrange-Formalismus},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_11.pdf}
}
2013 Gronek, M. Qalitätsplanung in der Entwurfsphase magnetgelagerter Systeme Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Die Markteinführung neuer Technologien und Produkte bedarf einer umfangreichen Vorarbeit. Diese beinhaltet einerseits die Entwicklung des Produktes selbst, aber gleichsam bedeutend sind die Maßnahmen zur Absicherung der Produkteigenschaften hinsichtlich der Anforderungen, die es zu erfüllen gilt. Sonder- und Einzelfertigung machen den wesentlichen Anteil in der Magnetlagertechnik aus, was dem Entwicklungsaufwand und den erforderlichen Komponenten geschuldet ist. Erreicht eine Magnetlagerentwicklung die Serienreife, so muss in den überwiegenden Fällen von einer anwendungsspezifischen Kleinserie gesprochen werden. Eine tatsächliche Standardisierung, die mit konventionellen Lagerungsarten vergleichbar wäre, gibt es nicht. Der Beitrag widmet sich dem Thema der Anforderungsanalyse einerseits aus systemtechnischer Sicht und weiter gefasst auf Anforderungen vom Anwender an das Produkt Magnetlager. Es werden die Aspekte der Qualitätsplanung und Risikominimierung für sicherheitsrelevante Maschinenbaugruppen erörtert.
BibTeX:
@inproceedings{WMLT9_12,
  author = {M. Gronek},
  title = {Qalitätsplanung in der Entwurfsphase magnetgelagerter Systeme },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_12.pdf}
}
2013 Gruber, W., Bauer, W., Amrhein, W. and Schöb, R. Betrachtungen zum lagerlosen Flux-switching Scheibenläufer Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Der lagerlose Flux-Switching Scheibenläufermotor ist ein sehr kompakt aufgebauter magnetisch gelagerter Antrieb, der gänzlich ohne Permanentmagnete im Rotor auskommt. Die Funktionsweise dieser neuartigen lagerlosen Motortopologie wird in diesem Aufsatz untersucht und die Eignung für einen Betrieb als lagerloser Motor mittels Gütefunktionalen bewertet. Dreidimensionale Finite-Elemente-Simulationen für eine vielversprechende Motorvariante liefern gute Ergebnisse, die in Zukunft auch mit einem Prototyp verifiziert werden sollen.
BibTeX:
@inproceedings{WMLT9_13,
  author = {W. Gruber and W. Bauer and W. Amrhein and R. Schöb},
  title = {Betrachtungen zum lagerlosen Flux-switching Scheibenläufer },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_13.pdf}
}
2013 Lehmann, R. Alternative Abstandserfassung mit Wirbelstromsensoren Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Wirbelstromsensoren finden, neben anderen Einsatzgebieten, häufig ihre Anwendung in aktiv magnetisch gelagerten Systemen. Sie gelten als besonders robust gegenüber ihren Umgebungseinflüssen, wie zum Beispiel Staub, Luftfeuchte oder elektromagnetischen Feldern. Die unterschiedlichen Preise dieser Abstandserfassungs-Systeme spiegeln sich in ihren Möglichkeiten der Parametrierung, Synchronisierung und in der Qualität ihrer Ausgangssignale wider. Beispielsweise sind einfach gehaltene Sensorsysteme relativ preisgünstig jedoch untereinander nicht synchronisierbar wobei hingegen synchronisierbare sehr teuer sind. Ebenfalls gibt es Unterschiede im Durchmesser der Sensoren, dem Erfassungsbereich und dem Zielmaterial. Eine besonders wichtige Eigenschaft ist zusätzlich die Grenzfrequenz. Am häufigsten verbreitet sind immer noch rein analoge Sensorsysteme. In dem in diesem Beitrag beschriebenen Projekt bestand die Zielstellung darin, eine eigene Elektronik für die Positionserfassung des Rotors im Magnetlager zu entwickeln. Das Komplettgerät sollte sich insbesondere durch eine hohe Grenzfrequenz auszeichnen, preisgünstiger, synchronisierbar, kalibrierbar sowie auch für eigens entwickelte unterschiedliche Sensortypen einsetzbar sein.
BibTeX:
@inproceedings{WMLT9_2,
  author = {R. Lehmann},
  title = {Alternative Abstandserfassung mit Wirbelstromsensoren},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_2.pdf}
}
2013 Neumann, H. and Panescu, C. MFLP – Magnet- und Fanglagerprüfstand des Zitauer Krafwerkslabors Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Der Einsatz von Magnetlagern in Kraftwerksmaschinen ist oftmals durch hohe Umgebungstemperaturen und zum Teil aggressive Medien begrenzt. Gründe dafür sind der Isolationsgrad der Wicklung und der Blechung bzw. die üblicherweise eingesetzten Materialien. Für die Wicklungen liegen die max. beherrschbaren Temperaturen bei 160 °C. Bekannte Lösungen, wie zum Beispiel keramische Drahtisolierungen, die Temperaturen bis 450 °C zulassen, sind sehr aufwendig und mit einer Reihe von Nachteilen behaftet. Neueste Entwicklungen auf dem Gebiet der Oberflächentechnologie und Materialforschung erschließen völlig neue Ansätze für die Isolierung und eröffnen damit die Möglichkeit für Hochtemperaturmagnetlager (HTAMB High Temperature Active Magnetic Bearing). Da-bei müssen nicht nur die Magnetlager, sondern auch die notwendigen Fanglager in die Betrachtung mit einbezogen werden.
BibTeX:
@inproceedings{WMLT9_3,
  author = {H. Neumann and C. Panescu},
  title = {MFLP – Magnet- und Fanglagerprüfstand des Zitauer Krafwerkslabors },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_3.pdf}
}
2013 Weidenmüller, F. and Nickel, A. Aufbau des digitalen Reglers am Beispiel PID-Regler, Regleung nach dem Prinzip Lokalisation Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Magnetische Lager sind strukturinstabil. Sie benötigen in mindestens einer Achse eine aktive Lagerung. Zur Positionierung des Rotors werden schnelle Regelkreise benötigt, die auf analoger oder digitaler Basis arbeiten. Dieser Beitrag beschäftigt sich mit dem Aufbau eines schnellen digitalen Regelkreises bestehend aus Messsystemen, digitalen Reglern, Koordinatentransformation und Leistungsverstärkern. Basierend auf diesem Aufbau werden regelungstechnische Abläufe anhand von Blockschaltbildern dargestellt. Regler- und Filtergleichungen werden in Form von zeitdiskreten IIR-Filtern aufgestellt und in eine für eine Implementierung auf dem digitalen Regler notwendige Schreibweise überführt. Im ersten Teil des Beitrags liegt der Fokus auf der Stabilisierung der Lageregelkreise mit PID-Reglern. Vergleichend dazu wird im zweiten Teil die Stabilisierung mit PL-Reglern vorgestellt. Zum Schluss erfolgt eine Gegenüberstellung von Vor- und Nachteilen beider Reglerstrukturen anhand zahlreicher Kriterien. Es werden Inbetriebnahmehinweise und Erfahrungen im praktischen Aufbau einzelner Komponenten gegeben.
BibTeX:
@inproceedings{WMLT9_4,
  author = {F. Weidenmüller and A. Nickel},
  title = {Aufbau des digitalen Reglers am Beispiel PID-Regler, Regleung nach dem Prinzip Lokalisation },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_4.pdf}
}
2013 Richter, M., Schaede, H., Quurck, L. and Rinderknecht, S. Untersuchung und Erhöhung der Praxistauglichkeit sensorloser Magnetlager nach dem „Direct Digital Inductance Estimation“-Konzept Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: In diesem Beitrag wird die Praxistauglichkeit sensorloser aktiver Magnetlager nach dem Prinzip der direk-ten Induktivitätsbestimmung theoretisch und praktisch untersucht. Anders als die Modulationsverfahren verwendet das Verfahren die Form des Stromripples des Spulenstroms zur Bestimmung der Induktivität des Aktors und darüber zur Positionsbestimmung. Der Einsatz von Regelplattformen mit hoher Abtastrate und großer Rechenleistung ermöglicht eine hohe Bandbreite der Positionsbestimmung, Antialiasingfilter werden nicht benötigt. Die Untersuchungen werden an einem einachsigen Prüfstand in Differenzanordnung mit praxisnaher Aktorik durchgeführt. Die Ergebnisse zeigen, dass durch den kleinen Luftspalt und Sättigungseffekte im Eisen des Aktors die Positionsbestimmung erschwert wird. Beide Beschränkungen können allerdings durch softwareseitige Erweiterungen kompensiert werden. Weiterhin resultiert aus induzierten Wirbelströmen eine von der Frequenz der Kraftstellung abhängige Beeinflussung der Induktivität und damit der Positionsbestimmung.
BibTeX:
@inproceedings{WMLT9_5,
  author = {M. Richter and H. Schaede and L. Quurck and St. Rinderknecht},
  title = {Untersuchung und Erhöhung der Praxistauglichkeit sensorloser Magnetlager nach dem „Direct Digital Inductance Estimation“-Konzept },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_5.pdf}
}
2013 Rudolph, J., Werner, R. and Maximow, I. Messung magnetischer Streufüsse zur Bestimmung der Wellenposition im Magnetlager Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Magnetlager stellen hoch komplexe mechatronische Systeme dar. Sie eignen sich besonders für Spezialanwendungen, wie Neutronenstrahlchopper und Hochgeschwindigkeitsbearbeitungsmaschinen. Die Genauigkeit, mit der die Welle im Magnetlager positioniert werden kann, hängt maßgeblich von der Qualität der eingesetzten Messsysteme ab. Dabei stehen Eigenschaften wie Auflösungsvermögen, Genauigkeit und Dynamik in einem direkten Zusammenhang zu den Kosten, die für das Messsystem anfallen. Um den finanziellen Aufwand für die Fertigung von Magnetlagern inklusive notwendiger Sensorik zu reduzieren, wird ein Messsystem vorgeschlagen, das auf der Auswertung der magnetischen Streuflüsse außerhalb des Arbeitsluftspaltes basiert. Dazu werden zunächst theoretische Überlegungen angestellt und numerische Berechnungen durchgeführt. Die daraus abgeleiteten Aussagen werden im Anschluss durch praktische Messungen verifiziert. Im Ergebnis liegt ein Messsystem vor, auf dessen Grundlage eine stabile magnetische Lagerung ermöglicht wird.
BibTeX:
@inproceedings{WMLT9_6,
  author = {J. Rudolph and R. Werner and I. Maximow},
  title = {Messung magnetischer Streufüsse zur Bestimmung der Wellenposition im Magnetlager },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_6.pdf}
}
2013 Schleicher, A. and Werner, R. Lagerloser reluktanter Linearmotor mit gleicher Nuteilung in Ständer und Läufer Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Abstract is not available
BibTeX:
@inproceedings{WMLT9_7,
  author = {A. Schleicher and R. Werner},
  title = {Lagerloser reluktanter Linearmotor mit gleicher Nuteilung in Ständer und Läufer },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_7.pdf}
}
2013 Vanek, C., Worlitz, F. and Hecht, N. Validierung eines Gleitfanglagermodells durch Abwurfversuche Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Der Betrieb magnetgelagerter Maschinen erfordert grundsätzlich den Einsatz von Fanglagern. Diese nehmen den Rotor bei Maschinenstillstand, bei abgeschalteter Magnetlagerung oder bei Magnetlagerversagen auf. Es wird zwischen Wälz- und Gleitfanglagerungen unterschieden. Der Rotor-Fanglagerkontakt bei hohen Drehzahlen und großen mechanischen Belastungen ist durch enorme Kontaktkräfte und Relativgeschwindigkeiten zwischen Rotor und Stator gekennzeichnet. Das Fanglager muss den Rotor bis zum Stillstand sicher aufnehmen. Gegenwärtig werden bei schweren Rotoren, wie sie z. B. in Verdichtern, Pumpen und Turbinen zu finden sind, vorwiegend Wälzfanglager eingesetzt. Der komplexe Aufbau von Wälzlagern (Innenring, Außenring sowie Wälzelemente) gegenüber Gleitlagern (rotor- und statorseitige Laufbuchsen) führt, vor dem Hintergrund hoher mechanischer und thermischer Belastungen während des Eingriffes, zu erhöhten Aufwendungen bei der Konstruktion und Fertigung und damit zu hohen Kosten. Gleitfanglagerungen können eine sichere und kostengünstigere Alternative darstellen. Eine wichtige Voraussetzung dafür ist es, Gleitfanglager für solche extremen mechanischen und thermischen Belastungen an Turbomaschinen konstruktiv und werkstofftechnisch zu ertüchtigen. Für den erfolgreichen Einsatz von Gleitfanglagerlösungen ist die Beherrschung aller Ab-wurfszenarien durch das Fanglager nachzuweisen. Besonderes Augenmerk gilt hierbei den Steifigkeits- und Dämpfungswerten der Lagerung. Diese sind so zu wählen, dass der Rotor beim Durchfahren kritischer Drehzahlen im Fanglager keine unzulässig hohen Schwin-gungen auf die Maschine überträgt. Zur Sicherstellung dieser Eigenschaften sind im Vorfeld der Konstruktion für alle relevan-ten Fälle Simulationsrechnungen durchzufüh-ren. Dazu wurde das Gleitlager modelliert und Simulationsrechnungen unter Berücksichti-gung der Rotordynamik durchgeführt. Die Validierung der Modelle erfolgte auf der Grundlage von Experimenten an einem Kleinversuchsstand mit verschiedenen Gleitfanglagern. Die Ergebnisse dieser Versuche wurden zudem den Ergebnissen von Versuchen mit Wälzfanglagern am selben Versuchsstand gegenübergestellt und mit diesen verglichen. Im Beitrag werden das Gleitlagermodell und erste Simulationsergebnisse sowie die Ergebnisse der Experimente am Kleinversuchsstand vorgestellt.
BibTeX:
@inproceedings{WMLT9_8,
  author = {C. Vanek and F. Worlitz and N. Hecht},
  title = {Validierung eines Gleitfanglagermodells durch Abwurfversuche },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_8.pdf}
}
2013 Bahr, F., Melzer, M. and Karnaushenko, D. Erfassung der Lufspaltinduktion aktiver Magnetlager auf Basis ultradünner, flexibler Hall-Sensoren Proceedings of Workshop on Magnetic Bearing Technology 9  
Abstract: Abstract is not available
BibTeX:
@inproceedings{WMLT9_9,
  author = {F. Bahr and M. Melzer and D. Karnaushenko},
  title = {Erfassung der Lufspaltinduktion aktiver Magnetlager auf Basis ultradünner, flexibler Hall-Sensoren },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 9},
  year = {2013},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt9/wmlt9_9.pdf}
}
2012 Yu, C. and Xu, L. Auto-eliminating Clearance Auxiliary Bearings for Active Magnetic Bearing Systems Proceedings of ISMB13  
Abstract: An auto-eliminating clearance auxiliary bearing (ACAB) for Active Magnetic Bearing systems (AMBs) has been conceived and a prototype system tested. In the ACAB, a ball bearing is directly mounted on a rotor, and the outer race of the ball bearing is surrounded by a series of interconnected supporters. In the open position, a clearance exists between the outer race and the ACAB supporters. When the rotor mounted with ball bearing drop on ACAB supporter(s) due to either an AMB system failure or transient shock, the generated friction between the outer race and supporter(s) will rotate the supporters circumferentially to eliminate the clearance and re-center the ball bearing and rotor. Since the clearance is eliminated, the impact force between the outer race and supporters is reduced and the possibility of backward whirl is eliminated. This paper presents the design methodology of those supporters. And a preliminary feasibility prototype experimental rig was established under the situation of simulated AMB system failure. Experimental results demonstrate feasibility of the ACAB.
BibTeX:
@inproceedings{ISMB13_11,
  author = {Chengtao Yu and Longxiang Xu},
  title = {Auto-eliminating Clearance Auxiliary Bearings for Active Magnetic Bearing Systems},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_11.pdf}
}
2012 Grabner, H., Silber, S. and Amrhein, W. Bearingless Torque Motor - Modeling and Control Proceedings of ISMB13  
Abstract: In recent years, demands for magnetically supported direct drives which operate con-tactless and feature a high torque capacity arise in industry. This paper presents an advantageous solution for a bearingless torque motor. The proposed configuration consists of a six phase winding cofiguration with concentrated coils in double star connection to keep power electronics efforts to a minimum. The six phase winding system generates simultaneously both, the actively controlled motor torque and the radial bearing forces for radial position control. The disk shaped hollow shaft rotor carries 26 permanent mag-nets. To reduce the systems costs, tilting de ection and the axial position of the rotor are stabilized passively by the magnetic reluctance forces. The mathematical model and an appropriate control for current and voltage drivers is introduced. Finally, the prototype motor is shown with special attention to the angle and rotor position sensor evaluation.
BibTeX:
@inproceedings{ISMB13_12,
  author = {Herbert Grabner and Siegfried Silber and Wolfgang Amrhein},
  title = {Bearingless Torque Motor - Modeling and Control},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_12.pdf}
}
2012 Silber, S., Grabner, H., Lohninger, R. and Amrhein, W. Design Aspects of Bearingless Torque Motors Proceedings of ISMB13  
Abstract: In this paper novel topologies of multiphase bearingless motors featuring outstanding motor effciency and high radial force capacity are presented. For a systematic layout a simple design guideline is provided. These motors are especially suitable for applications where high torque at relatively low speed is demanded, therefore this configuration is referred to as bearingless torque motor. Since there are no dedicated bearing and motor windings the winding scheme becomes very simple and is furthermore characterized by concentrated coils only. Motor designs with different pole and slot configurations are compared by means of appropriate performance indexes. For the most promising design a demonstrator was manufactured and tested.
BibTeX:
@inproceedings{ISMB13_13,
  author = {Siegfried Silber and Herbert Grabner and Robert Lohninger and Wolfgang Amrhein},
  title = {Design Aspects of Bearingless Torque Motors},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_13.pdf}
}
2012 Wang, X. and Wang, W. Research on the Equivalent Friction Force and Power Loss of a Magnetic Bearing Proceedings of ISMB13  
Abstract: Compared with rolling bearing and sliding bearing, there is no mechanical friction and wear in magnetic bearing because there is no mechanical contact. But there is still a similar character with the mechanical friction force while magnetic bearing working. The force can be defined as an equivalent friction force for the similar to mechanical friction force. The equivalent friction force is studied and is used in calculation of power loss in magnetic bearing. It means that the power loss in magnetic bearing is equal to the equivalent friction force multiplied by the rotor speed. The definitions of the power loss in magnetic bearing and friction character are the same as those of rolling bearing and sliding bearing. A research method of equivalent friction force and power loss in magnetic bearing which is analogy of the conventional research method of rolling bearing and sliding bearing is put forward. A calculation method of power loss in magnetic bearing is presented. All of this will benefit the design of magnetic bearing system.
BibTeX:
@inproceedings{ISMB13_15,
  author = {Xiaoguang Wang and Wei Wang},
  title = {Research on the Equivalent Friction Force and Power Loss of a Magnetic Bearing},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_15.pdf}
}
2012 Marth, E., Jungmayr, G., Panholzer, M. and Amrhein, W. Optimization of Stiffness per Magnet Volume Ratio of Discrete and Continuous Halbach Type Permanent Magnetic Bearings Proceedings of ISMB13  
Abstract: To optimize stiffness per magnet volume ratio, whichs major intentions are to reduce the costs and to preserve material resources, an energy based analytical calculation method of the radial stiffness for permanent magnetic bearings with arbitrary magnetization is introduced. To simplify the calculations the stiffness is calculated from a planar model, what means that the annular ring magnets are treated as infinitely long parallel bars. The error made by neglecting the curvature effect is investigated and shows to be negligible for reasonable designs. Using this calculation method, optimal geometries for permanent magnetic ring bearings with Halbach type magnetization are presented. Thereby, discrete Halbach stacking, i.e. several stacked rings with rotating magnetization from axial to radial and so on, and continuous Halbach magnetization, i.e. one magnet that is magnetized sinusoidal, is distinguished. To show the possible improvement of stiffness per magnet volume ratio, also the characterizing values for standard single ring bearings and standard stacked structures are calculated.
BibTeX:
@inproceedings{ISMB13_16,
  author = {Edmund Marth and Gerald Jungmayr and Martin Panholzer and Wolfgang Amrhein},
  title = {Optimization of Stiffness per Magnet Volume Ratio of Discrete and Continuous Halbach Type Permanent Magnetic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_16.pdf}
}
2012 Defoy, B., Alban, T. and Mahfoud, J. Numerical Assessment of a Polar Fuzzy Controller for Centrifugal Compressors Proceedings of ISMB13  
Abstract: The aim of this study was to develop and to apply a new control approach dedicated to turbomachinery. The controller is fuzzy based usinginputs expressed in polar coordinates. The advantage is that it manages two significant physical quantities, namely tangential and radial speeds that are related to steady state and transient behaviors respectively. A simple synchronous filter is associated to the controller in order to enhance the ratio command force / bearing dynamic capacity. The approach was previously applied experimentally with success for the control of an academic test rig. It is adapted here for the control of an industrial compressor whose flexible rotor is supported by Active Magnetic Bearings (AMB). At this stage, only numerical investigations are performed. The controller has to satisfy the standards and the end users requirements. In addition, it should be easy to implement. The behavior of the machine studied is assessed for several configurations of unbalances. Tests that correspond to usual industrial excitations (subsynchronous excitation, impulse response at nominal speed) are also carried out. Results obtained are satisfactory and give insight into the potential of the approach. In addition, and as the fuzzy controller parametersare independent from the rotor design, the approach is a first step for the standardization ofmagnetic bearing controller synthesis.
BibTeX:
@inproceedings{ISMB13_17,
  author = {Benjamin Defoy and Thomas Alban and Jarir Mahfoud},
  title = {Numerical Assessment of a Polar Fuzzy Controller for Centrifugal Compressors},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_17.pdf}
}
2012 Buechsenschuetz, M. and Sattel, T. Controller Design for a High Precision Elastically Supported Hybrid Active Magnetic Guidance Proceedings of ISMB13  
Abstract: The design of multi coordinate drives (MCD) with nanometre positioning uncertainty and long planar motion range of several hundred millimetres is a worldwide research challenge. Ac-tive magnetic guidance (AMG) is suitable for these precision applications due to its non-contact support principle. One drawback is the heat generation due to ohmic loss in the control coil which should be minimized and kept constant to meet high precision demands [1, pp. 83-84]. In [2] an elastically supported hybrid active magnetic guidance (ES-HAMG) is proposed. A hybrid magnet combines a permanent magnet with a coil, additionally it is connected in series with a mechanical spring. This device is capable of reducing the thermal dissipation by 80% at varying load force on a sample ES-HAMG. This contribution gives a more comprehensive view on ES-HAMG inMCD than [2]. A model to estimate possible savings in power dissipation is derived in detail. The employed controller design theory is given. Experiments confirm theoretical energy savings and the nanopositioning capabilities.
BibTeX:
@inproceedings{ISMB13_18,
  author = {Mirko Buechsenschuetz and Thomas Sattel},
  title = {Controller Design for a High Precision Elastically Supported Hybrid Active Magnetic Guidance},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_18.pdf}
}
2012 Impinna, F., Detoni, J.G., Amati, N. and Tonoli, A. Non-dimensional design approach for Electrodynamic Bearings Proceedings of ISMB13  
Abstract: Electrodynamic bearings (EDBs) are passive magnetic bearings that exploit the interaction between eddy currents developed in a rotating conductor and a static magnetic field to generate forces. Similar to other types of magnetic suspensions, EDBs provide contactless support, thus avoiding problems with lubrication, friction and wear. The most interesting aspect of EDBs is that levitation can be obtained by passive means, hence, no electronic equipment, such as power electronics or sensors, are necessary. Despite their promising characteristics, rotors running on EDBs are still lacking a design procedure; furthermore, at present the static behavior of a bearing can only be defined by means of finite element analyses. The aim of the present paper is to present a methodology that allows performing a first approximation design without resorting to detailed FE analyses. The methodology is based on the use of non-dimensional parameters, similar to the analysis of fluid bearings (Sommerfeld number). The non-dimensional quantities are derived using dimensional analysis, and contain the main geometrical and physical parameters determining the EDBs' performance. The relation between the non-dimensional quantities characterizing the static performance of the EDB is derived using FE simulations and is presented in the form of graphs.
BibTeX:
@inproceedings{ISMB13_19,
  author = {Fabrizio Impinna and Joaquim Girardello Detoni and Nicola Amati and Andrea Tonoli},
  title = {Non-dimensional design approach for Electrodynamic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_19.pdf}
}
2012 Qian, K.-X. World-unique Permanent Maglev Turbine Reaches a Speed Over 30,000 rpm Proceedings of ISMB13  
Abstract: The author's former works on developing a permanent maglev heart pump have been questioned because the rotor of the heart pump has only ca. 20g weight and there is liquid in the pump. To levitate a heavier rotor with passive magnetic(PM) bearing and to avoid the possibility that a fluid bearing may act on the levitation of the rotor, the author applied the passive magnetic bearing in turbine machine. A prototype of permanent maglev gas turbine was developed. The device has a rotor and a stator, both radial and axial PM bearings were used to support the rotor weighing over 2kg. The gap between the rotor and the stator was 1mm, thereby no possible air bearing can be built up to support the rotor together with the PM bearings. First experiment by a model permanent maglev turbine demonstrated that the rotor's maximal eccentric distance, measured by 4 Hall sensors, would be smaller than the gap between the rotor and the stator, if the rotating speed was higher than 1800rpm, indicating that the rotor had no contact with the stator and thus was levitated stably under the action of PM bearing alone. In more extensive experiments with this prototype, the rotating speed of the device reached 30,773rpm, a value approaching that in practical application. It can be concluded that PM bearing can merely support the rotor of a gas turbine being suspended fully and stably in the stator, same as that in blood pump; this result may overturn the principle acknowledged worldwide for hundreds years that permanent maglev could not be stable.
BibTeX:
@inproceedings{ISMB13_2,
  author = {Kun-Xi Qian},
  title = {World-unique Permanent Maglev Turbine Reaches a Speed Over 30,000 rpm},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_2.pdf}
}
2012 Sun, F., Oka, K., Jin, J.J., Hong, T. and Lu, Y. Semi-Zero Power Control of a Permanent Magnetic Suspension System with Constant Air Gap Length Proceedings of ISMB13  
Abstract: This paper proposes a semi-zero power control method of a permanent magnetic suspension system using a flux path control mechanism with a constant air gap. This permanent magnetic suspension system consists of a disk-type permanent magnet, two “F� type iron cores, a rotary actuator with an encoder and a reducer, and a suspended object with a bar shape. In this system, the gravitational force of the suspended object is transmitted to the base part of the system, and the actuator only drives the permanent magnet rotate. Therefore, this system can realize the semi-zero power control. Moreover, when the mass of suspended object increases, the system just changes the bias angle of the permanent magnet, and maintains the air gap length constant. In another way, this system also can maintain the bias angle of magnet constant, and changes the air gap length short to realize the semi-zero power control. This paper focuses on the semi-zero power suspension characteristics of this system, elaborates the system’s mechanism, and analyzes the semi-zero power suspension performances with a constant air gap length.
BibTeX:
@inproceedings{ISMB13_20,
  author = {Feng Sun and Koichi Oka and Jun Jie Jin and Tao Hong and Yingyuan Lu},
  title = {Semi-Zero Power Control of a Permanent Magnetic Suspension System with Constant Air Gap Length},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_20.pdf}
}
2012 Denk, J., Köpken, H.-G., Stoiber, D. and Viering, F. Active Magnetic Bearing Systems for Turbo Machine Applications based on Standard Drive Technology Proceedings of ISMB13  
Abstract: Around two decades ago, active magnetic bearings (AMB) were introduced into O&G-applications (Oil & Gas- applications), but never gained any relevant market share in large turbomachinery. This paper discusses how standard drive technology from machine tool applications can be used to control AMB systems and how the integrated data acquisition functions simplify the commissioning process. As a proof of the concept, results of prototype testing with a 5 MW induction motor are presented.
BibTeX:
@inproceedings{ISMB13_21,
  author = {Joachim Denk and Hans-Georg Köpken and Dietmar Stoiber and Frank Viering},
  title = {Active Magnetic Bearing Systems for Turbo Machine Applications based on Standard Drive Technology},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_21.pdf}
}
2012 Mizuno, T., Nishimura, K., Ishino, Y. and Takasaki, M. Realization of Parallel-Connected Double Magnetic Suspension Proceedings of ISMB13  
Abstract: A double magnetic suspension system with parallel-connected coils is actualized in this work. The double magnetic suspension system includes a pair of subsystems, each of them has an electromagnet and a floator, and controls them by a single power amplifier solely. Double suspension systems are classified into two types based on the connection of the double coils: series connection and parallel connection. The feasibility of double magnetic suspension with series-connected coils has been already demonstrated in the previous works. This work focuses on double magnetic suspension with parallel-connected coils. The conditions for the system to be controllable are presented for its mathematical model. The feasibility of double magnetic suspension is demonstrated experimentally.
BibTeX:
@inproceedings{ISMB13_22,
  author = {Takeshi Mizuno and Kazuya Nishimura and Yuji Ishino and Masaya Takasaki},
  title = {Realization of Parallel-Connected Double Magnetic Suspension},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_22.pdf}
}
2012 Mizuno, T., Sakai, Y., Ishino, Y. and Takasaki, M. Fabrication of a New Wind Tunnel for Spinning Body Using Magnetic Suspension Proceedings of ISMB13  
Abstract: A wind-tunnel system for spinning body has been proposed to measure hydrodynamic forces acting on the body. In the proposed system, a ferromagnetic sphere (body) is suspended and rotated by electromagnets. The forces acting on the body are measured from the control signal for suspension. In this work, a wind-tunnel system with 60 60? mm was fabricated. It has eight electromagnets placed around the wind-tunnel, and a newly fabricated 3-axis optical sensor that operates in the fully differential mode. Stable suspension and three-dimensional positioning of the body were achieved in the developed system. Spinning of the body was realized by superimposing two-phase AC signals on the control signal. The hydrodynamic forces acting on the spinning body are measured successfully.
BibTeX:
@inproceedings{ISMB13_23,
  author = {Takeshi Mizuno and Yasuhiro Sakai and Yuji Ishino and Masaya Takasaki},
  title = {Fabrication of a New Wind Tunnel for Spinning Body Using Magnetic Suspension},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_23.pdf}
}
2012 Cao, G., Li, H., Huang, S., Pan, J. and Qiu, H. Development of a Control Platform for the Magnetic Suspension System Proceedings of ISMB13  
Abstract: A highly integrated open control platform for control algorithms development of magnetic suspension system is proposed based on MATLAB/Simulink, dSPACE and DSP. The schema and work principle of the control platform are presented. A robust H8controller as an example for the system is designed in detail to verify the control platform. Experimental results show that the control platform is successfully set up for carrying out research of complex control algorithms and education of control theory.
BibTeX:
@inproceedings{ISMB13_25,
  author = {Guangzhong Cao and Hanyi Li and Sudan Huang and J.F. Pan and Hong Qiu},
  title = {Development of a Control Platform for the Magnetic Suspension System},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_25.pdf}
}
2012 Okada, Y., Miyoshi, T., Masuzawa, T., Enokizono, M. and Kondo, R. Lorentz Force type Self-Bearing Motor for Centrifugal Heart Pump Proceedings of ISMB13  
Abstract: Highly efficient Lorentz force type self-bearing motor is developed. High rotor pole flux density and ampere turns of stator coils are the key technology for strong levitated motor. For this purpose Halbach magnet array and pressed flat coils are used to get high performance. The coil thickness is only 1.6 [mm] with one coil winding of 66 turns. The peak flux density in air gap is about 0.6 [T]. The rotor can run up to 9,000 [rpm] with maximum efficiency over 70 [%]. This self-bearing motor is tried to apply to the centrifugal heart pump.
BibTeX:
@inproceedings{ISMB13_26,
  author = {Yohji Okada and Tadafumi Miyoshi and Toru Masuzawa and Masato Enokizono and Ryou Kondo},
  title = {Lorentz Force type Self-Bearing Motor for Centrifugal Heart Pump},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_26.pdf}
}
2012 Zhang, W., Zhu, H. and Cao, L. Accurate Modeling of Radial Suspension Force on AC Magnetic Bearings Proceedings of ISMB13  
Abstract: This paper presents a new modeling method based on Maxwell tensor method for radial suspension forces of AC magnetic bearing. Comparing existing method, the invention explicitly designed for AC magnetic bearing is more accurate. Take the AC hybrid magnetic bearing (AC HMB) for example, this paper presents the mathematically modeling process of radial suspension forces with the proposed method. In a comparison of the model established by equivalent magnetic circuit method and by the proposed method, the high uniformity is revealed in its expression form (the only difference is the coefficient between them). To illustrate the precision of the proposed modeling approach, relevant verification experiment are designed and conducted. Indeed, the experimental results show that the proposed modeling method is more accurate than the traditional method (equivalent magnetic circuit method).
BibTeX:
@inproceedings{ISMB13_27,
  author = {Weiyu Zhang and Huangqiu Zhu and Li Cao},
  title = {Accurate Modeling of Radial Suspension Force on AC Magnetic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_27.pdf}
}
2012 Jastrzebski, R., Smirnov, A., Lin, Z., Pyrhönen, O. and Allaire, P. Extended Kalman Filter Applied to an AMB System with Strong Magnetic Saturation Proceedings of ISMB13  
Abstract: The main aim of the paper is to operate an AMB system inside the magnetically saturated region. We investigate how to stabilize a highly nonlinear AMB system with the actuator magnetic saturation by estimating the system states and parameters of the unconstrained bearing in real time. The stabilization is achieved by a combination of the controller and the extended Kalman filter to estimate the states of the plant. In the extended Kalman filter, the magnetization behavior has been modeled by using low-order piecewise polynomial approximation. The extended Kalman applied to the AMB system introduces an additional challenge because of the computational burden, numerical stability when computing the inverse of the innovation covariance matrix, and the non-continuous derivative in the computed Jacobeans. Feasibility of different control configurations is examined. As the case study we use the 1 DOF balancing beam model. The proposed solution for the system operation in the magnetic saturation provides such benefits as: the reduced size and costs of bearings, improved robust performance and stability, and an increased controllability region with respect to control variables.
BibTeX:
@inproceedings{ISMB13_28,
  author = {Rafal Jastrzebski and Alexander Smirnov and Zongli Lin and Olli Pyrhönen and Paul Allaire},
  title = {Extended Kalman Filter Applied to an AMB System with Strong Magnetic Saturation},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_28.pdf}
}
2012 Jin, C., Zhu, Y. and Xu, L. Dynamic Responses of Rotor Drops onto Double-Decker Catcher Bearing Proceedings of ISMB13  
Abstract: In an active magnetic bearing (AMB) system, the catcher bearings (CBs) are indispensable to protect the rotor and stator in case the magnetic bearings fail. Most of the former researches associated with CBs are mainly focused on the dynamic responses of the rotor drops onto traditional single-decker catcher bearings (SDCBs). Based on the analysis of the disadvantages of SDCBs, a new type of double-decker catcher bearings (DDCBs) is proposed to enhance the CB work performance in AMB system. Detailed simulation models containing rigid rotor model, contact model between rotor and inner race, DDCB model as well as SDCB model after rotor drop are established using Multi-body dynamics simulation software MSC.ADAMS. Then, using those established models the dynamic responses of rotor drops onto DDCBs and SDCBs are respectively simulated. The rotor orbits, contact forces and spin speeds of various parts after AMB failure are mainly analyzed. The simulation result shows that DDCBs can effectively improve reduce the following vibrations and impacts. Finally, rotor drop experiments choosing different types of CBs are carried out on the established AMB test bench. Rotor orbits and the rotating speeds of both inner race and intermediate races after rotor drop are synchronously measured. The experiment results verify the advantages of DDCB and the correctness of simulation analysis. The studies provide certain theoretical and experimental references for the application of DDCBs in AMB system.
BibTeX:
@inproceedings{ISMB13_29,
  author = {Chaowu Jin and Yili Zhu and Longxiang Xu},
  title = {Dynamic Responses of Rotor Drops onto Double-Decker Catcher Bearing},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_29.pdf}
}
2012 Li, P., Sahinkaya, N. and Keogh, P. Active Magnetic and Touchdown Bearings to Encourage Rotor Re-Levitation from a Persistent Contact Condition Proceedings of ISMB13  
Abstract: Magnetic bearing systems are commonly used for high speed rotor applications, having particular advantages in low pressure/vacuum environments. The benefits of using magnetic bearing systems are well documented in terms of low fiction and controllable stiffness and damping. In order to protect magnetic bearings in cases of power failure, intermittent faults and unexpected external disturbances, secondary back-up or touchdown bearings are usually included so that rotor/stator contact is prevented. If, for any reason, a rotor should make contact with a touchdown bearing, the ensuing rotor dynamic response will depend on operational parameters and any residual rotor unbalance distribution. The influence of unbalance force distributions on the contact rotor dynamics are demonstrated in this paper. Interactions between a rotor and touchdown bearings can cause relatively high contact forces that could be damaging in terms of direct mechanical stresses and through induced heat inputs when slip occurs. Inorder to alleviate the contact problem an actively controlled touchdown bearing system has been proposed to reduce contact forces and, where possible, recover rotor positional control and return it to a condition of contact-free levitation. Active touchdown bearing control may be applied together with magnetic bearing control and suggested strategies to encourage rotor contact-free levitation are assessed in this paper.
BibTeX:
@inproceedings{ISMB13_30,
  author = {Peichao Li and Necip Sahinkaya and Patrick Keogh},
  title = {Active Magnetic and Touchdown Bearings to Encourage Rotor Re-Levitation from a Persistent Contact Condition},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_30.pdf}
}
2012 Anantachaisilp, P., Lin, Z. and Allaire, P. PID Tuning Methods for Active Magnetic Bearing Systems Proceedings of ISMB13  
Abstract: The use of active magnetic bearings (AMBs) in place of traditional mechanical bearings for rotating machinery has been increasing. AMBs have been used not only in research studies, but also in a wide range of industrial applications. One of the key challenges in AMB appli-cations is the design of control systems that maintain stability in the presence of external loads and disturbances. The most commonly used controller for AMB systems is the Proportional-Integral-Derivative (PID) controller, whose design involves the tuning of control coefficients. Since manual tuning of these coefficients is time consuming, different systematic tuning methods have been developed and reported on in the literature. This paper examines some of these tuning methods in AMB control systems. Both simulation and experiments are carried out on an AMB test rig to compare the performance of the closed-loop systems resulting from these tuning meth-ods in terms of steady state accuracy and robustness. Simulation and experiments of each tuning method are conducted at rotational speeds ranging from 2,000 rpm to 11,000 rpm to evaluate the response peak (orbital size). Also, the frequency responses of the sensitivity function (S) under PID controllers tuned with different methods are measured and used to compare the robustness of the closed-loop system.
BibTeX:
@inproceedings{ISMB13_31,
  author = {Parinya Anantachaisilp and Zongli Lin and Paul Allaire},
  title = {PID Tuning Methods for Active Magnetic Bearing Systems},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_31.pdf}
}
2012 Rodriguez, E. and Stephan, R. Study of Passive Magnetic Bearings for Vertical-Axis Wind Turbines Proceedings of ISMB13  
Abstract: The increasing world energy demand as well as the necessity of environmental clean developments has turned the industry attention to improvements in renewable energy. In this context, wind power plants present technological advantages as an excellent source of clean energy. The current vertical-axis wind turbines are going to be a novel energy supplier in urban centers due to both low-cost and low-impact architectural design. Moreover, they have good performance even in the presence of turbulent winds. A magnetic suspension can greatly improve the performance, expanding the operating points to very low wind velocities. Active magnetic bearings present limiting factors such as power consumption and complexity of the system, due to sensors, power electronic circuits and the control system. In other way, passive techniques, which use permanent magnets and/or superconductors, can be alternatives in some applications. This paper presents a contribution to the design of passive magnetic bearings for vertical-axis wind turbines. Finite element simulations and experimental data will be presented.
BibTeX:
@inproceedings{ISMB13_32,
  author = {Elkin Rodriguez and Richard Stephan},
  title = {Study of Passive Magnetic Bearings for Vertical-Axis Wind Turbines},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_32.pdf}
}
2012 Zhang, J., Fang, S., Wu, H., Wang, X. and Song, C. Study on Fluid Characteristics of Centrifugal Maglev Blood Pump Proceedings of ISMB13  
Abstract: Optimal designing the magnetic bearing structure of the Centrifugal Maglev Blood Pump, then using the speed coefficient method to design a six-blade impeller and pump chamber, and using fluent software to simulate the pressure field, velocity field and flow field of the centrifugal maglev blood pump.
BibTeX:
@inproceedings{ISMB13_33,
  author = {Jinguang Zhang and Siyuan Fang and Huachun Wu and Xiaoguang Wang and Chunsheng Song},
  title = {Study on Fluid Characteristics of Centrifugal Maglev Blood Pump},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_33.pdf}
}
2012 Asama, J., Oiwa, T. and Chiba, A. Performance Improvement of a One-DOF Actively Positioned Bearingless Motor Proceedings of ISMB13  
Abstract: Conventional bearingless motors and magnetic bearings with one- to five-degrees-of-freedom (DOF) active positioning require a number of inverter modules, windings, position sensors, and electromagnets. To reduce the size and power consumption of this type of motor, the authors previously proposed a one-DOF actively positioned bearingless motor, referred to as a single-drive bearingless motor that has only one three-phase winding set and one three-phase inverter. Although the successful non-contact operation of this motor was demonstrated previously, a rotor of the test machine ran up to only 800 r/min because of serious resonance. The aim of this study was to improve the rotation performance of the single-drive bearingless motor. The cause of the rotor vibration was a discontinuous distribution of the magnetic flux density in the air-gap. One possible solution has been proposed in this paper. The test machine with an improved rotor was successfully driven up to 2000 r/min.
BibTeX:
@inproceedings{ISMB13_34,
  author = {Junichi Asama and Takaaki Oiwa and Akira Chiba},
  title = {Performance Improvement of a One-DOF Actively Positioned Bearingless Motor},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_34.pdf}
}
2012 Ishino, Y., Takasaki, M. and Mizuno, T. Development of a Solar Photovoltaic Magnetic Suspension System Proceedings of ISMB13  
Abstract: Extra low-power suspension in gravitational field is achieved by a magnetic suspension system whose power source is solely solar photovoltaics. Presently, solar photovoltaic cells become more efficient and cost-saving year by year. In this study, solar photovoltaic generation technique is combined with the zero-power magnetic suspension. The zero-power control achieves the steady state in which the attractive force produced by the permanent magnets balances the weight of the floator and the control current converges to zero. In this system, the power necessary for generating the suspension forceis very small. However, the peripheral devices including sensors and a controller need power for operation. The power consumed in the peripheral devices becomes dominant in the total power in the steady state. In this work, dedicated power-saving peripheral devices are newlyfabricated. The average power consumed in the electromagnet is 20[mW] to suspend a 90-glammass, while the power consumed in the peripheral devices is 24[mW]. The photovoltaic cells used in the apparatus has a maximum power capacity of about 2[W] in the summer sunlightof 120[kLx]. The system achieves stable suspension even under the illuminance of a fluorescent lamp of 7[kLx].
BibTeX:
@inproceedings{ISMB13_35,
  author = {Yuji Ishino and Masaya Takasaki and Takesh Mizuno},
  title = {Development of a Solar Photovoltaic Magnetic Suspension System},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_35.pdf}
}
2012 Ueno, S. and Sahinkaya, M.N. Variable Bias Current Control and Adaptive Parameter Estimation in Active Magnetic Bearings Proceedings of ISMB13  
Abstract: Reducing the energy consumption of active magnetic bearings is important for some appli-cations to reduce operating cost, expand the operating period, and avoid heat generation. The power loss of magnetic bearings consists of ohmic, electronic circuit, windage, eddy current, and hysteresis losses. With the exception of windage, these losses are functions of the coil currents, therefore, minimization of these has a significant effect on the overall energy efficiency of a mag-netic bearing. In this paper, a variable bias current scheme is introduced to minimize the energy consumption without altering the dynamic performance. Since the current stiffness and negative stiffness of the magnetic bearing are functions of the bias current, it is possible to achieve invari-ant dynamics for various bias current settings. The optimum bias current is calculated from the demand bearing force and instantaneous rotor displacement, but errors in model parameters may result in changes in system dynamics. Therefore, correct parameter values are required for invari-ant dynamics. In this paper, estimation methods for various parameter errors are introduced and verified experimentally. The proposed variable bias current controller and parameter estimation methods yield significant energy savings, are simple to implement and applicable to a wide range of magnetic bearing systems.
BibTeX:
@inproceedings{ISMB13_37,
  author = {Satoshi Ueno and M. Necip Sahinkaya},
  title = {Variable Bias Current Control and Adaptive Parameter Estimation in Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_37.pdf}
}
2012 Sugimoto, H. and Chiba, A. Precise Measurement of Suspension Force in Two-Axis Actively-Positioned Bearingless Motor for a Comparison to 3D-FEM Analysis Proceedings of ISMB13  
Abstract: Bearingless motors are required in centrifugal pumps, reaction wheels and artificial hearts for the applications in semiconductor manufacturing, space applications and medical devices, respectively. Two-axis actively regulated bearingless motors have the advantages of low cost and compactness. Only two degrees of freedom are actively regulated in the radial x-ydirections. Thus it is known that tilting motion causes seriousinterference to the radial position regulation. The interference occurs when the following three positions are not exactly corresponding; (i) the center of gravity of the rotor, (ii) the application point of the suspension force, and (iii) the position of the displacement sensors. A discrepancyin these positions causes tilting and axial displacements, which results in a reduction of radial suspension force. In this paper, a 3D-FEM analysis of the radial suspension force is carried out taking into account the rotor tilting displacement. A precise measurement method of the static radial suspension force is proposed and tested. The experiment results indicate a good correspondence to the finite element analysis.
BibTeX:
@inproceedings{ISMB13_38,
  author = {Hiroya Sugimoto and Akira Chiba},
  title = {Precise Measurement of Suspension Force in Two-Axis Actively-Positioned Bearingless Motor for a Comparison to 3D-FEM Analysis},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_38.pdf}
}
2012 Asama, J., Takemoto, M., Sugimoto, H. and Chiba, A. Performance Investigation and Power Factor Improvement of a Consequent-Pole Type Bearingless Motor Proceedings of ISMB13  
Abstract: The authors have developed a five-axis actively positioned bearingless drive system intended for a use as an industrial contamination-free centrifugal pump. It includes 1.2 kW consequent-pole type bearingless motor for torque generation and radial/tilting motion control. The aim of this paper is to investigate the motor performance with a test machine. In addition, a proposed rotor is found to improve power factor of a motor function. Based on the three-dimensional finite element method (3D-FEM) analysis, the effectiveness of the proposed structure has been verified in this paper.
BibTeX:
@inproceedings{ISMB13_39,
  author = {Junichi Asama and Masatsugu Takemoto and Hiroya Sugimoto and Akira Chiba},
  title = {Performance Investigation and Power Factor Improvement of a Consequent-Pole Type Bearingless Motor},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_39.pdf}
}
2012 Kluyskens, V. and Dehez, B. Analysis of the stability and the consumption of an electrodynamic bearing for different operation conditions Proceedings of ISMB13  
Abstract: In centering electrodynamic bearings, the guiding forces result from the interaction between eddy currents generated by a magnetic flux variation in conductors and the magnetic field. Predicting the dynamical behavior of this kind of bearings is not easy given the interactions between the electromagnetic nature of the forces and the rotational machinery aspects. In this paper, an electromechanical model, able to explain, predict, analyze and simulate the dynamical behavior of bearings submitted to eddy current forces, is applied on a homopolar null-flux electrodynamic bearing. The identification of the model’s parameters is done based on quasi-static FEM simulation results. Thanks to the insight the electromechanical model gives on the physics involved in the bearing, the dynamical stability and the stiffness of the bearing are analyzed as a function of the bearing spin speed. For various operation conditions like a constant external load or a static unbalance, the behavior of the electrodynamic bearing is simulated and examined using the electromechanical model. For all these operation conditions, the influence of the external damping, necessary to stabilize the system is analyzed. The amount of necessary damping to introduce is discussed and also its impact on the overall bearing consumption.
BibTeX:
@inproceedings{ISMB13_4,
  author = {Virginie Kluyskens and Bruno Dehez},
  title = {Analysis of the stability and the consumption of an electrodynamic bearing for different operation conditions},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_4.pdf}
}
2012 Jungmayr, G., Marth, E., Panholzer, M., Amrhein, W. and Weidenholzer, G. Fast approximate calculation of the radial and tilt stiffness of magnetic bearings using magnetostatic 2D finite element analysis Proceedings of ISMB13  
Abstract: In order to calculate the dynamic behavior of magnetically levitated rotors (eigenfrequencies, rotor deflections...), the knowledge of the radial and tilt stiffness of the active and passive magnetic bearings is necessary. An optimization of the stability against exter-nal disturbances and internal excitations (unbalance, magnetic tolerances) requires a large number of calculations of these magnetic bearing parts. Therefore, a short calculation time of the reluctance forces is crucial. As an original rotational symmetry is lost in case of a radially de ected or tilted rotor, the tilt stiffness and the radial stiffness of magnetic bearing parts are usually calculated with a 3D-FE software. These time-consuming cal-culations prevent fast optimizations of the rotor dynamics. This paper shows a method for the approximate calculation of the radial and tilt stiffness of rotationally symmetric magnetostatic problems by using a 2D-FE program. The accuracy of the approximation method will be verified by comparing the results with the exact analytical solution of a pure permanent magnetic configuration.
BibTeX:
@inproceedings{ISMB13_40,
  author = {Gerald Jungmayr and Edmund Marth and Martin Panholzer and Wolfgang Amrhein and Guenther Weidenholzer},
  title = {Fast approximate calculation of the radial and tilt stiffness of magnetic bearings using magnetostatic 2D finite element analysis},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_40.pdf}
}
2012 Masahiro, O., Toru, M. and Eisuke, T. 5-DOF control double stator motor for paediatric ventricular assist device Proceedings of ISMB13  
Abstract: We have developed a maglev ventricular assist device (VAD) for use in infant patients, which requires the device to be smaller compared to adult devices. In this research, a miniaturized axial gap maglev motor for use as a paediatric VAD is reported. In addition, radial position control theory using P±2 pole algorithm is proposed, and the feasibility of radial position control with the miniaturized axial gap maglev motor is examined by using magnetic field analysis. The double stator motor consists of a top stator, a bottom stator and a levitated rotor set between the stators which have an identical structure. A double stator mechanism has been adopted to enhance motor torque with a smaller device size and a large air-gap. The rotational speed and the axial position of the rotor are regulated independently based on a vector control algorithm. The inclination and the radial position of the rotor are regulated using P±2 pole algorithm. The designed motor which has an outer diameter of 28 mm and total height of 41 mm can produce a radial force using P±2 pole algorithm, and indicates a possibility of 5 degrees of freedom (DOF) controlled axial gap double stator motor.
BibTeX:
@inproceedings{ISMB13_41,
  author = {Osa Masahiro and Masuzawa Toru and Tatsumi Eisuke},
  title = {5-DOF control double stator motor for paediatric ventricular assist device},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_41.pdf}
}
2012 Panholzer, M., Jungmayr, G., Marth, E., Passenbrunner, J. and Amrhein, W. Performance and Dynamic Properties of an Active Axial Bearing Proceedings of ISMB13  
Abstract: In magnetically levitated systems at least one degree of freedom has to be actively stabilized. This is usually achieved with a linear magnetic actuator. If not prevented by e.g. lamination, eddy currents take place in the field conducting iron. These eddy currents have a strong effect on the field distribution in the iron and further reduce the force per current at higher frequencies. In this paper investigate the dynamic properties of a non laminated actuator biased with a permanent magnet in the rotor is anlaysed. It is shown that the voltage to force transfer function is practically unaffected by eddy currents.
BibTeX:
@inproceedings{ISMB13_42,
  author = {Martin Panholzer and Gerald Jungmayr and Edmund Marth and Josef Passenbrunner and Wolfgang Amrhein},
  title = {Performance and Dynamic Properties of an Active Axial Bearing},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_42.pdf}
}
2012 Deckert, A. Thermal-electromechanical Modeling of Magnetically Levitated Rotors under Vacuum Conditions Proceedings of ISMB13  
Abstract: This paper introduces a possibility to couple the thermal analyses of a magnetically levitated rotor, which is driven under vacuum condition, with models of its electromechanical loop. By means of this coupling, effects can be represented that are not visible when considering the ther-mal behavior and the electromechanical loop separately. The models have been parameterized for a huge number of geometrical and physical properties. The derived algorithms are implemented in MATLAB and accessible via the graphical user interface “MagBeS – Magnetic Bearing Sim-ulator�. This makes the algorithm applicable for different users and varying systems. Analyses are presented that demonstrate the interaction of the thermal and electromechanical behavior and it is shown that additional potentially critical operating modes can be identified. Furthermore, a novel approach for the experimental determination of the occurring rotor losses by means of temperature measurements and thermal analyses is presented.
BibTeX:
@inproceedings{ISMB13_43,
  author = {Antje Deckert},
  title = {Thermal-electromechanical Modeling of Magnetically Levitated Rotors under Vacuum Conditions},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_43.pdf}
}
2012 Pesch, A. and Sawicki, J. Application of Robust Control to Chatter Attenuation for a High-Speed Machining Spindle on Active Magnetic Bearings Proceedings of ISMB13  
Abstract: The purpose of this work is to demonstrate a robust control strategy to avoid machining chatter in a high-speed machining spindle levitated on active magnetic bearings. Chatter avoidance is an important aspect in machining because chatter limits the material removal rate and inhibits production. A method is implemented which uses µ-synthesis AMB control with a cutting force model in the controller design process. Such an approach causes the controller to stabilize the naturally unstable cutting process, avoiding chatter and resulting in smoother surface finish, longer tool life and increased material removal rate. Stability lobe diagrams are calculated for the new control strategy showing increased critical feed rate and confirmed through numerical simulations. The developed method is implemented experimentally on the high-speed AMB machining spindle. Impulse hammer testing is performed to measure the controlled spindle’s transfer function and evaluate chatter free machining suitability.
BibTeX:
@inproceedings{ISMB13_44,
  author = {Alexander Pesch and Jerzy Sawicki},
  title = {Application of Robust Control to Chatter Attenuation for a High-Speed Machining Spindle on Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_44.pdf}
}
2012 Mamiya, T., Hijikata, W. and Shinshi, T. A Disposable Magnetic Bearing System for an Extracorporeal Centrifugal Blood Pump Proceedings of ISMB13  
Abstract: In order to increase the design flexibility of the rotor/impeller in an extracorporeal maglev centrifugal blood pump and realize a magnet-less disposable pump head, a novel combination of a radial magnetic bearing and a magnetic coupling disk for transmitting the rotational torque from the motor, which surrounds the disposable magnet-less rotor/impeller, is proposed. The magnetic bearing system actively controls the radial motion of the rotor/impeller and passively controls motion in the other directions. Contactless stable levitation and rotation of the rotor at speeds from 0 to 3,200rpm were realized with a bearing system fabricated for a 50mm diameter rotor.
BibTeX:
@inproceedings{ISMB13_45,
  author = {Taichi Mamiya and Wataru Hijikata and Tadahiko Shinshi},
  title = {A Disposable Magnetic Bearing System for an Extracorporeal Centrifugal Blood Pump},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_45.pdf}
}
2012 Ariga, Y. and Watanabe, K. Unbalance Control of Magnetic Bearings by Multi-Degree of Freedom Internal Model Control Proceedings of ISMB13  
Abstract: This paper suggests a method to control an unbalance vibration of the magnetic bearing by multi-degree of freedom internal model controller which is called Model Bridge Control. This control method can compensate for each control problem, e.g. robust stability and uncertainty compensation, responses, disturbance rejection. By focusing on a disturbance compensator, this paper put forward a control system which rejects agitation due to unbalance. In this paper, a controller design method using a disturbance compensation characteristic of model bridge control is shown. The controller gets possible to control an unbalance forced vibration with the specific frequency by using a disturbance model. The effectiveness of the proposed method has been clarified by simulation.
BibTeX:
@inproceedings{ISMB13_46,
  author = {Yuichi Ariga and Keiji Watanabe},
  title = {Unbalance Control of Magnetic Bearings by Multi-Degree of Freedom Internal Model Control},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_46.pdf}
}
2012 Fan, Y., Liu, S. and Li, H. Application of 115kW blower supported by magnetic bearing Proceedings of ISMB13  
Abstract: Because of its superior characteristics, magnetic bearing have been applied in many fields. The topic of this paper is the control system ofmagnetic bearing in blower application. Thermal expansion effects have the impact on measurement of axial displacement, we use two eddy current sensors which are in the radial symmetrical arrangement to achieve measurement of the axial displacement, and theoreticalcalculations and experiment verified the possibility of this method.In order to reduce vibration of the rotor, a chebyshev IInotch filter is designed to suppress the special frequency, the effect of notch depth and bandwidth are discussed in the paper, through the rational allocation, the vibration of rotor are greatly suppressed; In order to improve the response of the rotor, phase compensation are used in this system, through the use of two phase compensation,the stability of the rotor rotation are improved. Simulation and experimental results show that the system has a good dynamic characteristics, the speed of the rotor is 15000rpm.
BibTeX:
@inproceedings{ISMB13_47,
  author = {Youpeng Fan and Shuqin Liu and Hongwei Li },
  title = {Application of 115kW blower supported by magnetic bearing},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_47.pdf}
}
2012 Liu, S., Bian, Z. and Cheng, Z. The application of the permanent magnet bearings in the Vertical Axis Wind Turbine Proceedings of ISMB13  
Abstract: This paper introduces the structural design of the permanent magnetic bearing for axial suspension on wind turbine, including the supporting schemes and the selection of the permanent magnetic material. The calcula-tion of the bearing capacity and the stiffness are given, and suitable stiffness can reduce the vibration caused by the changes of the wind load. Experimental comparation of wind turbines starting torque supported by the magnetic bearing and by the mechanicalbearing was carried out. And it is proved that the magnetic bearing can significantly reduce the starting torque of the wind turbine, thereby the starting wind velocity can be also reduced. Meanwhile, the wind turbine can work for a long time without lubrication, which affords lower maintenance costs, reduces the noise and greatly raises the efficiency.
BibTeX:
@inproceedings{ISMB13_48,
  author = {Shuqin Liu and Zhongguo Bian and Zhaoliang Cheng},
  title = {The application of the permanent magnet bearings in the Vertical Axis Wind Turbine},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_48.pdf}
}
2012 Li, D., Liu, S. and Bian, B. Research on the Beat Vibration of Active Magnetic Bearings Proceedings of ISMB13  
Abstract: Beat vibration is a kind of special vibration which sometimes arise in the active magnetic bearing. This vibration can smear the quality of magnetic bearings seriously. Based on the analysis of the synthesis mechanism of the beat vibration, this paper investigated the origin of the beat vibration in the magnetic bearing. According to the special electrical and machinery structure of the magnetic bearing, the source and the formation of the two sub-vibrations (the vibration with the same frequency of the rotate speed of the rotor and the vibration with the same frequency of the rotating magnetic field in induction motor) which synthesize the beat vibration were analyzed. Finally, method of inhibition of the beat vibration is given.
BibTeX:
@inproceedings{ISMB13_49,
  author = {Deguang Li and Shuqin Liu and Bin Bian },
  title = {Research on the Beat Vibration of Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_49.pdf}
}
2012 Zhang, K., Zhang, X. and Dai, X. Vibration Problems in a Turbo Molecular Pump with Active Magnetic Bearings Proceedings of ISMB13  
Abstract: In experimental tests of a proto-type 2000L turbo molecular pump suspended by 5-DOF AMBs, complex vibration problems had been met. They were caused by different reasons including rotor bending modes, rotor gyroscopic effects, pump blade modes and a vibration mode created by interaction of the dynamics of the rotor and the pump motor. They influenced the pump stability and had to be considered carefully in AMB controller designs to run the rotor to a target speed of 24000 rpm. Different methods were used to deal with these vibration problems. The gyroscopic effects were dealt with using cross feedback control methods. Other vibrations, including the bending mode vibrations, the pump blade vibrations and so on, were dealt with using phase shaping control methods. Experiment results concerning them were provided. With the suitable controller design and the appropriate consideration of the dynamic problems, the rotor was successfully accelerated to its target speed.
BibTeX:
@inproceedings{ISMB13_5,
  author = {Kai Zhang and Xiaozhang Zhang and Xingjian Dai},
  title = {Vibration Problems in a Turbo Molecular Pump with Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_5.pdf}
}
2012 Lee, J.-H. A Study on an Effect of the Flux feedback on an Open-loop Characteristic of the Magnetic Levitation System Proceedings of ISMB13  
Abstract: This paper deals with an open-loop characteristic of a magnetically levitated system including flux feedback. In order to design a controller to obtain a good disturbance rejection and to be insensitive to parameter variations, it might be useful to employ a flux feedback loop. The air gap flux which can be sensed by a proper sensor has linear relationship with respect to the change of the current and the air gap. This linear property decreases the inherent nonlinearity of the magnetic suspension system that is caused by the coupling between the electrical actuator and the mechanical plant. Simulation results show that the flux feedback loop makes an improvement of the performance of the magnetic suspension system against the load variations.
BibTeX:
@inproceedings{ISMB13_50,
  author = {Jun-Ho Lee},
  title = {A Study on an Effect of the Flux feedback on an Open-loop Characteristic of the Magnetic Levitation System },
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_50.pdf}
}
2012 Abrahamsson, J., Hedlund, M. and Bernhoff, H. Prototype of Kinetic Energy Storage System for Electrified Utility Vehicles in Urban Traffic Proceedings of ISMB13  
Abstract: This paper presents theoretical and experimental results on the ongoing construction of a high-speed (30000 rpm) kinetic energy storage system (KESS). The purpose of the device is to function as a power buffer storing up to 1kWh, primarily for utility vehicles in urban traffic. The KESS is connected in series between the primary power source and the tractionmotor of the vehi-cle. It comprises a composite rimof carbon and glass fiber in an epoxymatrix. The power to/from the rotating rim is transferred through an integrated double wound three-phase PM machine. The machine is levitated axially using four units with segmented Halbach arrays in a repulsive con-figuration. Radial centering is achieved through eight separate active electromagnetic actuators controlled by an FPGA. The geometries of the passive thrust units as well as the active actuators were designed using linked CAD and FEM tools controlled by advanced optimization algorithms. The simulated repulsive force from the thrust magnets was verified experimentally. Additionally, the corresponding negative stiffness in radial direction as well as the power loss due to induced eddy currents were simulated. The optimization of the active magnetic bearing (AMB) actuators resulted in a geometry with low resistive power loss, while generating a high current stiffness at the expense of maximum force.
BibTeX:
@inproceedings{ISMB13_51,
  author = {Johan Abrahamsson and Magnus Hedlund and Hans Bernhoff},
  title = {Prototype of Kinetic Energy Storage System for Electrified Utility Vehicles in Urban Traffic},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_51.pdf}
}
2012 Rensburg, J.J.V., Schoor, G.V. and Vuuren, P.V. The characterization of the severity of rotor delevitation events: A parametric study Proceedings of ISMB13  
Abstract: Active magnetic bearing (AMB) failure and the ensuing rotor behavior is a very important aspect of AMB safety. A model for this rotor behavior was developed and was used to characterize the severity of rotor delevitation events. The characterization was done by means of severity indicators derived from the rotor behavior within the backup bearings. The indicator is a quantitative value that can be used to compare different delevitation events. The indicator presented in this paper is the non-dimensionalised velocity of the geometric center of the rotor (Vval). This indicator only requires the rotational speed and position data of the rotor to determine the Vval quantity. This ensures that this value can be determined for most current operational systems and on historical data logged from previous rotor delevitation events. In order to validate Vval, a comparison was done between simulated and experimental rotor drops and their associated Vval values. The model used to produce the simulation results is BBSim. Experimental results were obtained on a 4-axis suspended rotor, modified to use rolling element backup bearings.
BibTeX:
@inproceedings{ISMB13_52,
  author = {Jan Janse Van Rensburg and George Van Schoor and Pieter Van Vuuren},
  title = {The characterization of the severity of rotor delevitation events: A parametric study},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_52.pdf}
}
2012 Schaede, H., Schleiffer, J.-E., Beckerle, P. and Rinderknecht, S. An Approach for the Holistic Integration of Fault Detection and Diagnosis into Active Magnetic Bearing Systems Proceedings of ISMB13  
Abstract: Present research on fault detection and diagnosis on magnetic bearing systems aims on the diagnosis of the state of single components, such as sensor and actuator faults or fault states of the plant. Although these methods often have the potential to detect more than one fault state, there is no fault detection method allowing the detection of all possible faults . This paper describes aconceptional approach to combine different fault detection methods aiming on a holistic online diagnosis of the active magnetic bearing system consisting of the functional components controller, actuator, plant and sensor. On the example of a centrifugal pump in active magnetic bearings this approach gives the possibility to combine fault detection methods detecting internal faults of the bearing system as well as the determination of the overall system status, e.g., the duty point of the pump, based on the signals of the active magnetic bearing system. This approach allows integrating new functions into the active magnetic bearing system via an enhancement of the software without changing the widely developed hardware of active magnetic bearings.
BibTeX:
@inproceedings{ISMB13_53,
  author = {Hendrik Schaede and Jean-Eric Schleiffer and Philipp Beckerle and Stephan Rinderknecht},
  title = {An Approach for the Holistic Integration of Fault Detection and Diagnosis into Active Magnetic Bearing Systems},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_53.pdf}
}
2012 Yang, B., Hu, Y. and Song, C. Study on Active Vibration Isolation Control for Electromagnetic Floating Raft Platform Proceedings of ISMB13  
Abstract: The normalized FLMS algorithm makes the convergence coefficient vary with time, which makes the adaptive process achieve a compromise between the convergence coefficient and the steady state error and overcomes the problem that the convergence factor is difficult to select, ca used by that the power of the reference signal cannot be accurately estimated or vary too fast with time. In this paper, the magnetic suspension f loating raft vibration isolation system acting as the object, the FIR filter being introduced as a feed-forward link, and the mean square error of systematic deviation operating as the performance indicators, the normalized FLMS algorithm is used for self-optimization to obtain the optimal controller parameters. The simulation results show that the normalized FLMS algorithm has better effect over convergence speed and vibration isolation compared with the ordinary FLMS algorithm. So it was applied to active control system of the magnetic suspension floating raft vibration isolation, and achieved better effect.
BibTeX:
@inproceedings{ISMB13_54,
  author = {Beibei Yang and Yefa Hu and Chunsheng Song },
  title = {Study on Active Vibration Isolation Control for Electromagnetic Floating Raft Platform},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_54.pdf}
}
2012 Kumar, P., Wright, D.D. and Jayawant, R. Sending PWM Down Extended Magnet Cables Proceedings of ISMB13  
Abstract: With a high power active magnetic bearing system, rapid changes in the magnet coil current are achieved by switching a high DC link forcing voltage onto the inductive load for short periods of time using Pulse Width modulation (PWM). In the steady state the on time of the voltage is a very small proportion of the cycle period such thatthe average voltage is sufficient to maintain the DC current through the DC resistance of the load. In some situations where it is necessary to have a large separation between the PWM driving amplifier and the load, the cable between behaves as a badly terminated transmission line. Significant reflections on the PWM pulse waveform are able to cause potentially damaging voltage overshoots up to around twice the original voltage. Conventional source and or load termination impedances would introduce unacceptable power losses. Using filters to limit the bandwidth goingdown the cable is both costly and has broadly similar effect to reducing the forcing voltage. This paper describes tests of a dynamic termination method where most of the power that would otherwise be lost is returned to the source of the DC link, giving dramatic improvement in the waveform quality.
BibTeX:
@inproceedings{ISMB13_55,
  author = {Praveen Kumar and Dr Derek Wright and Richard Jayawant},
  title = {Sending PWM Down Extended Magnet Cables},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_55.pdf}
}
2012 Victor, V.F., Lopes, J.S.B., Junior, L.D.S., Filho, J.C.D.S. and Salazar, A.O. Analysis and Study of a Bearingless AC Motor type Divided Winding, Based on a Conventional Squirrel Cage Induction Motor Proceedings of ISMB13  
Abstract: This paper shows the analysis and study of a bearingless AC Motor type divided winding for a conventional squirrel cage Induction Motor, IM. The conventional IM is used as a bearingless motor for artificial-lift oil proposes, allowing a reduction in maintenance and operation costs. The goal of this paper is improving electromagnetic forces performance, such as the Lorentz and Maxwell forces, allowing rotor positio ning at the rotation axis. It was used a simulator based on the finite element method for acquiring load results for a 375 kW, 380V, 4 -poles, 60Hz, 1.04 Nm, IM motor. Experimental results show that is possible to use a conventional IM as a bearingless motor, achieving a 80% efficiency. This paper presents simulated and experimental results that demonstrated the operation of the IM bearingless -type split coil built from a conventional induction motor.
BibTeX:
@inproceedings{ISMB13_56,
  author = {Valci F. Victor and José Soares Batista Lopes and Luciano Dos S. Junior and João Coelho De S. Filho and Andres O. Salazar},
  title = {Analysis and Study of a Bearingless AC Motor type Divided Winding, Based on a Conventional Squirrel Cage Induction Motor},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_56.pdf}
}
2012 Na, U.J. Design and Analysis of an Electromagnet Biased Integrated Radial-Axial Magnetic Bearing Proceedings of ISMB13  
Abstract: The theory for a new electromagnetically biased diskless combined radial and axial magnetic bearing is developed. A typical magnetic bearing system is composed of two radial magnetic bearings and an axial magnetic bearing. The axial magnetic bearing with a large axial disk usually limits rotor dynamic performance and makes assembling and disassembling difficult for maintenance work. This paper proposesa novel electromagnet biased integrated radial-axial magnetic bearing without axial disk. The axial magnetic bearing unit in this integrated magnetic bearing utilizes reluctance forces such that the axial disk can be removed from the bearing unit. The 4-pole homopolar type radial magnetic bearing unit is also designed and analyzed. 3-D flux analysis are also provided to illustrate the novel diskless integrated magnetic bearing.
BibTeX:
@inproceedings{ISMB13_57,
  author = {Uhn Joo Na},
  title = {Design and Analysis of an Electromagnet Biased Integrated Radial-Axial Magnetic Bearing},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_57.pdf}
}
2012 Ji, M. and Zhou, J. Identification of Support Parameters of Magnetic Bearing Based on Model Updating Method Proceedings of ISMB13  
Abstract: The stiffness and damping of magnetic bearings play an important role in the stability of high speed rotor system. In order to obtain the reliable and accurate support parameters of magnetic bearing, an identification method based on model updating is proposed in this paper. Successful identification of support parameters is based on an accurate system model. The accurate rotor model is first derived by model updating using frequency response function (FRF) data. Then, the identification of support parameters of magnetic bearings is completed by model updating method based on the unbalance response. Unbalance response of magnetic bearing rotor system with assumed initial support parameters can be calculated by the transfer matrix method. Based on an optimization algorithm, the minimum error between the calculated and measured unbalance response is achieved. The support parameters which were used to calculate the unbalance response are the identified stiffness and damping of magnetic bearings. Finally, the effectiveness and accuracy of the identification method are verified by simulation.
BibTeX:
@inproceedings{ISMB13_59,
  author = {Minlai Ji and Jin Zhou},
  title = {Identification of Support Parameters of Magnetic Bearing Based on Model Updating Method},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_59.pdf}
}
2012 Ji, L. and Xu, L. Research on an Inverter-fed Six-Pole Permanent Magnet Biased Magnetic Bearing Proceedings of ISMB13  
Abstract: The configuration and working principle of a six-pole heteropolar permanent magnet biased magnetic bearing is introduced. And the mathematical models of the suspension forces are deduced through coordinate transformation. Then the paper studies the performances of the magnetic bearing for various area ratios between the permanent magnetic pole and the electromagnetic pole. The mathematical models are verified by finite element simulation. The results show that the current stiffness error rate between theoretical calculation and finite-element simulation is less than 3%, while the displacement stiffness error rate is much greater. A controller for this magnetic bearing is designed. To confirm the controller is effective, experiments were carried out with the proposed magnetic bearing system. The results all show that the rotor can be suspended steadily and the whole control system has good dynamic and static performance with robustness. Finally, power losses tests were done. As a result, the power losses of proposed six-pole magnetic bearing are only 9.85% of the traditional eight-pole active magnetic bearing for the same bias magnetic flux density.
BibTeX:
@inproceedings{ISMB13_6,
  author = {Li Ji and Longxiang Xu },
  title = {Research on an Inverter-fed Six-Pole Permanent Magnet Biased Magnetic Bearing},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_6.pdf}
}
2012 Silvagni, M., Bonfitto, A. and Tonoli, A. Self Powered Transformer Eddy Current Damper for Vibration Control of Rotors Proceedings of ISMB13  
Abstract: The vibration control of rotors is usually performed using passive dampers, in layouts where the support of the rotating parts is achieved by rolling-element or hydrodynamic type bearings. Active magnetic bearings could be a promising however they show serious drawbacks, in terms of mass, at least when the generation of strong magnetic forces is required. Electromagnetic dampers seem a valid alternative to viscoelastic/hydraulic dampers and to active magnetic bearings because their simpler architecture, and, if of transformer type, also for the absence of power electronics, position sensors and any fast feedback loop. However transformer eddy current dampers require a constant voltage power supply (usually based on common power electronics) often integrated with active electronics components. To reduce cost, improve the reliability some applications could benefit a simplified system avoiding active components and providing the required energy with an embedded generator. The aim of the present paper is to propose a self-powered damper to fulfil these requirements. A three-phase permanent magnet electric generator (connected to the rotating shaft) generates the required power for the damping device. The generator is connected to the damping circuit by means of suitable impedance and a three-phase rectifier.
BibTeX:
@inproceedings{ISMB13_60,
  author = {Mario Silvagni and Angelo Bonfitto and Andrea Tonoli},
  title = {Self Powered Transformer Eddy Current Damper for Vibration Control of Rotors},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_60.pdf}
}
2012 Duesterhaupt, S. and Worlitz, F. Complex and Integrated Methods for the Reliability Analysis of Contactless Magnetic Bearings Proceedings of ISMB13  
Abstract: In many fields of energy technology the proof of reliability is required for the application of magnetic bearings. The application of active magnetic bearings in turbo machines for power plants is characterized by extreme process and environmental conditions. The parameters varie-gate due to manufacturing tolerances and the influence of specific operation and load conditions of the control loop components of a magnetic bearing. That involves a load-dependent reliabil-ity of the bearing components. Therefore an active magnetic bearing which is under nominal conditions in terms of its function, may fail due to drifts of mechanical, electrical and magnetic parameters. The objective of this project is the reliability analysis of active magnetic bearings considering their nonlinearities. The analysis will be carried out by means of appropriate methods which consider the specific fuzzy parameters compared to conventional approaches. The part failure probability of the several components will be determined by Monte-Carlo-Simulations. The fail-ure probability of the whole system will be summarized by use of a fault tree analysis. Whether any components have to be integrated redundantly/diversely will be determined in the early de-sign process.
BibTeX:
@inproceedings{ISMB13_61,
  author = {Stephan Duesterhaupt and Frank Worlitz},
  title = {Complex and Integrated Methods for the Reliability Analysis of Contactless Magnetic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_61.pdf}
}
2012 Yoon, S.Y., Lin, Z. and Allaire, P.E. On the Control of Single Stage Centrifugal Compressor Surge with Active Magnetic Bearings Proceedings of ISMB13  
Abstract: This paper presents a comprehensive step-by-step description of how to design and implement an Active Magnetic Bearing (AMB) based compressor surge controller, including experimental control results to demonstrate the effectiveness of the given approach. First, we provide a com-plete description of the industrial-size compressor test rig with AMBs that was specifically built for this study. Next, a detailed derivation of the dynamic equations describing the compressor flow is presented. The compressor model is later used in the synthesis of the model-based surge controller algorithm, which is implemented in the compressor test rig and tested experimentally. Illustrative details of the controller design, implementation, and testing are included.
BibTeX:
@inproceedings{ISMB13_62,
  author = {Se Young Yoon and Zongli Lin and Paul E. Allaire},
  title = {On the Control of Single Stage Centrifugal Compressor Surge with Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_62.pdf}
}
2012 Yoon, S.Y., Lin, Z. and Allaire, P.E. Iterative Tuning of Linear Quadratic Controller for AMBs in a High Speed Compressor Proceedings of ISMB13  
Abstract: This paper presents the design of an Active Magnetic Bearing (AMB) rotor radial levitation controller using an iterative tuning method developed for the Linear Quadratic Gaussian (LQG) design problem. An iterative method is used to find the ideal pair of state and input weights in the LQG objective function that result in the best performance and stability robustness characteristics of the closed-loop AMB system. A search method is used to identify a set of input weight and state weight pairs that result in AMB levitation controllers that satisfy the necessary requirements for digital implementation. Furthermore, the stability and performance requirements from the API 617 and ISO 14839 standards for new compressors with AMB support are included in the controller design process. Finally, the derived LQG rotor levitation controller is implemented on a high speed centrifugal compressor test rig with a rigid rotor. Experimental results are presented and compared to the measurements obtained with a preliminary PID controller. The measured unbalance response and rotor orbit plots demonstrate the benefits of the proposed LQG method.
BibTeX:
@inproceedings{ISMB13_63,
  author = {Se Young Yoon and Zongli Lin and Paul E. Allaire},
  title = {Iterative Tuning of Linear Quadratic Controller for AMBs in a High Speed Compressor},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_63.pdf}
}
2012 Di, L., Mushi, S., Lin, Z. and Allaire, P. Characteristic Model Based All-coefficient Adaptive Control of a Flexible Rotor Suspended on Active Magnetic Bearings Proceedings of ISMB13  
Abstract: Active magnetic bearings (AMBs) have been used in many high-speed rotating machinery ap-plications. Because of the nonlinear characteristics of magnetic bearings and complex dynamics of the flexible rotors, the problems of stabilization and disturbance rejection need to be exten-sively addressed for their smooth operation over a wide operating speed range. Conventional controller such as the proportional-integral-derivative (PID) design has played a major role in most AMB related applications. Although it is easy to implement, there exist limitations and drawbacks. The µ -synthesis approach can fulfill the requirement of robust performance, but it relies on the plant and uncertainty models, which are sometimes difficult to acquire for practical systems. This paper explores the use of the characteristic model based all-coefficient adaptive control (ACAC) method to stabilize a flexible rotor AMB system. This new control method does not require an actual model of the system. Both simulation and experimental results have shown its strong potential to perform well in spite of its simplicity.
BibTeX:
@inproceedings{ISMB13_64,
  author = {Long Di and Simon Mushi and Zongli Lin and Paul Allaire},
  title = {Characteristic Model Based All-coefficient Adaptive Control of a Flexible Rotor Suspended on Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_64.pdf}
}
2012 Palazzolo, A., Johnson, C., Thomas, E., Preuss, J., Tucker, R. and Provenza, A. Zero Gravity Test of a 40,000 RPM Flywheel Proceedings of ISMB13  
Abstract: A zero gravity flight is considered a nearly mandatory prerequisite for flight experiments on the Space Shuttle or International Space Station ISS. NASA Glenn and the Texas A&M Center for Space Power funded an effort to successfully operate a high speed 40,000 rpm flywheel during approximately 100 zero-g parabolic flight trajectories.The total flywheel energy storage system FESS was designed, built and tested at the lead author’s Texas A&M laboratory. The magnetic bearings have a fault-tolerant, homopolar design with a load capacity of about 100 lbs in the radial and axial directions. The paper includes design and fabrication details of the flywheel, magnetic suspension and the power, sensing and control systems, and also simulation and flight test results. Other magnetic bearing work presently ongoing in the lead author’s lab is also highlighted.
BibTeX:
@inproceedings{ISMB13_65,
  author = {Alan Palazzolo and Clinton Johnson and Erwin Thomas and Jason Preuss and Randall Tucker and Andrew Provenza},
  title = {Zero Gravity Test of a 40,000 RPM Flywheel},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_65.pdf}
}
2012 Maslen, E., Cloud, C.H., Hauge, T., Kibsgaard, S.T. and Lie, J.A. Unbalance Response Assessment of a Subsea Compressor Proceedings of ISMB13  
Abstract: Robustness to unbalance degradation is examined for a subsea compression application in-volving a hermetically sealed, integrated motor-compressor supported on active magnetic bear-ings. The unique rotordynamic analysis methodology employs induced infinity norm principles to determine whether various limits, such as probe vibration, seal clearances and AMB force capacities, are exceeded for worst case unbalance distributions. The compressor’s acceptability with respect to API unbalance response design criteria is examined. Additional results indicate that, by introducing speed-scheduled synchronous filter control, the machine should be able to handle significant balance degradation (approximately 7.5x the API allowable residual) before reaching the ISO recommended shutdown vibration levels. For this particular design/application, it was determined that, with the nominal feedback con-troller, the unbalance capacity is dictated by the AMB dynamic capacity, not by probe vibration or seal clearance limits. Such knowledge can be vital to the end-user and manufacturer where, if unbalance degradation capacity is less than expected for the particular service, design changes can be made to help ensure that the machine’s desired robustness and service life are achieved.
BibTeX:
@inproceedings{ISMB13_66,
  author = {Eric Maslen and C. Hunter Cloud and Trym Hauge and Svend Tarald Kibsgaard and John Arild Lie},
  title = {Unbalance Response Assessment of a Subsea Compressor},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_66.pdf}
}
2012 Turpault, S., Levine, J. and Silva, J.D. Modeling and Motion Planning of the Magnetic Vector Potential in a Nonlaminated Active Thrust Bearing System Proceedings of ISMB13  
Abstract: We propose a physical model representing a non laminated active thrust bearing system, ob-tained via Maxwell’s equations, giving the magnetic vector potential with eddy currents. We show that this model is flat in a “practical� sense. In particular, motion planning of the magnetic flux and eddy currents can be easily deduced.
BibTeX:
@inproceedings{ISMB13_67,
  author = {Stephane Turpault and Jean Levine and Joaquim Da Silva},
  title = {Modeling and Motion Planning of the Magnetic Vector Potential in a Nonlaminated Active Thrust Bearing System},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_67.pdf}
}
2012 Mushi, S., Lin, Z. and Allaire, P. Active Control of Rotordynamic Instability in Turbomachinery Proceedings of ISMB13  
Abstract: The onset of rotordynamic instability is a significant challenge to successful design and oper-ation of high speed rotating machinery particularly gas compressors. The use of active magnetic bearings (AMBs) to support gas compressor rotors presents an ideal opportunity for the explo-ration of optimal and robust active vibration control algorithms. A notable advantage of AMBs is their ability to generate optimal support stiffness and damping characteristics. Unlike passive me-chanical bearings, the support characteristics of AMBs may be modified over the operating life of the system without any major hardware changes. The objective of this paper is to demonstrate the expansion of the stability region for an experimental rotor subject to destabilizing cross-coupled stiffness. A model-based control paradigm was followed to develop nominal and uncertain dy-namic models of the rotor-bearing system. Using m -synthesis several robust controllers were designed and implemented on the MBTRI hardware to investigate their effect on the stability threshold. The best controller established a thirty-six percent increase in the stability threshold over an existing benchmark controller. This represented an increase from fifty-six percent of the maximum achievable stability threshold to seventy-six percent. A damping ratio estimation al-gorithm was used to experimentally evaluate the sensitivity of the various controllers to varying cross-coupled stiffness.
BibTeX:
@inproceedings{ISMB13_68,
  author = {Simon Mushi and Zongli Lin and Paul Allaire},
  title = {Active Control of Rotordynamic Instability in Turbomachinery},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_68.pdf}
}
2012 Nakaya, B., Komori, M., Asami, K.-I. and Sakai, N. Magnetically Levitated Conveyer Using High Tc Superconducting Magnetic Bearings (SMBs) and Its Dynamic Characteristics Proceedings of ISMB13  
Abstract: Our group has developed a new conveyer using superconducting levitation. The conveyer is com-posed of a levitated table and a conveying table. The gap between levitated table and conveying table is detected by using a Hall sensor on the superconductor. The position of the table is controlled by us-ing the PD control. In this paper we discuss a superconducting magnetic bearing (SMB) with a central superconductor. A central superconductor improves stiffness of each direction. In addition, character-istics of magnetically levitated superconducting conveyer are studied when the levitated table moves in the y direction.
BibTeX:
@inproceedings{ISMB13_69,
  author = {Bumpei Nakaya and Mochimitsu Komori and Ken-Ichi Asami and Nobuo Sakai},
  title = {Magnetically Levitated Conveyer Using High Tc Superconducting Magnetic Bearings (SMBs) and Its Dynamic Characteristics},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_69.pdf}
}
2012 Chen, S.-L. and Lin, S.-Y. Imbalance Compensation for an AMB System with Adaptive Immersion & Invariance Control Proceedings of ISMB13  
Abstract: This study is concerned with the compensationof imbalance force existing in a three-pole active magnetic bearing (AMB) system. An adaptive compensation scheme is proposed using the method of immersion and invariance (I&I) control. The main idea of I&I control is to immerse a higher-order system intoa lower-order target system. In this study, the target system will be the three-pole AMB system with known imbalance that is stabilized by an integral sliding mode controller (ISMC). In practical applications, the imbalance force may be unknown and may be changing during operation. The information of imbalance needs to be estimated online in order to realize the ISMC levitation control. To this aim, the adaptive compensation scheme is incorporated into the ISMC controller so that the closed-loop system forms the higher-order system for the design of I&I control. Numerical simulations verify the effectiveness of the proposed adaptive compensator for mass imbalance.
BibTeX:
@inproceedings{ISMB13_7,
  author = {Shyh-Leh Chen and Shyu-Yu Lin},
  title = {Imbalance Compensation for an AMB System with Adaptive Immersion & Invariance Control},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_7.pdf}
}
2012 Takahashi, W., Komori, M., Matsushita, T., Koshizuka, N., Sakai, N. and Asami, K.-I. Basic Study on Energy Storage Flywheel System With a Suspended Flywheel Rotor Proceedings of ISMB13  
Abstract: In this paper, a new model of energy storage flywheel system is proposed. The energy storage flywheel system is composed of a superconducting stator, a flywheel rotor, an induction motor and some positioning actuators. The flywheel rotor is suspended by a superconducting stator with one end fixed to a stable base. The paper discusses basic and dynamic characteristics of the energy storage flywheel system. As a result, displacements of the stator and the flywheel rotor are related with each other.
BibTeX:
@inproceedings{ISMB13_70,
  author = {Wataru Takahashi and Mochimitsu Komori and Teruo Matsushita and Naoki Koshizuka and Nobuo Sakai and Ken-Ichi Asami},
  title = {Basic Study on Energy Storage Flywheel System With a Suspended Flywheel Rotor},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_70.pdf}
}
2012 Zhang, G., Zhang, H., Wang, X., Zhang, J., Sun, C. and Zhang, J. The Electromechanical Coupling Dynamical Model of Active Maglav EMALS Proceedings of ISMB13  
Abstract: EMALS is a take-off technology used in aircraft carrier. Now the technology is successful developed in US, which proves that it is possible. This paper put forward a design scheme in which the magnetic suspension technology is used in the EMALS. An electromechanical coupling dynamical model which not only includes the five degree of freedom controlled by maglev, but also includes the sixth degree of freedom of the linear motor will be set up in this paper. The model will be useful to the further study. keywords: active maglev, EMALS, dnamics, model
BibTeX:
@inproceedings{ISMB13_71,
  author = {Gang Zhang and Hailong Zhang and Xiping Wang and Jian Zhang and Chang Sun and Jiansheng Zhang},
  title = {The Electromechanical Coupling Dynamical Model of Active Maglav EMALS},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_71.pdf}
}
2012 Wei, C. and Söffker, D. Improving PID-Control of AMB-Rotor System Design I: Optimization Strategy Proceedings of ISMB13  
Abstract: Most of the industial active magnetic bearings (AMBs) are controlled by PID-Controllers. Usually a time-consuming iterately procedure is involed to design those PID-Controllers. In this contribution an optimization strategy is developed to design a complex PID-Controller. Multi-Objective Genetic Algorithms (MOGAs) are employed as the core of the complex optimization procedure to be used. The results are studied. Core of this contribution is the development of the optimization strategy, especially the combination of frequency and time domain-based com-ponents as well as the strategy for complex PID-Controller design. For validation purposes, a comparison between simulation and experimental results are presented in part II of the contribu-tion .
BibTeX:
@inproceedings{ISMB13_73,
  author = {Chunsheng Wei and Dirk Söffker},
  title = {Improving PID-Control of AMB-Rotor System Design I: Optimization Strategy},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_73.pdf}
}
2012 Wei, C. and Söffker, D. Improving PID-Control of AMB-Rotor System Design II: Experimental Results Proceedings of ISMB13  
Abstract: Most of the industial active magnetic bearings (AMBs) are controlled by PID-Controllers. Usually a time-consuming trial and error procedure is involed to design those PID-Controllers. In part I of this contribution an optimization strategy is introduced to design a complex PID-Controller structure of higher order to be applied on an industrial AMB system. For validation purposes, the selected optimal controllers obtained by using an optimization strategy are applied to a test-rig with a flexible rotor supported by AMBs. In part I of the contribution the control algorithm parameters are optimized, in this part II, the resulting control is implemented on a Digital Signal Processor (DSP) controlling the AMB-rotor system. In combination with a test-rig experiments are performed. Within this contribution various aspects of the implementation are discussed; results are shown.
BibTeX:
@inproceedings{ISMB13_74,
  author = {Chunsheng Wei and Dirk Söffker},
  title = {Improving PID-Control of AMB-Rotor System Design II: Experimental Results},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_74.pdf}
}
2012 Zhu, C., Zhang, Q. and Chen, L. Modal Decoupling Control for Active Magnetic Bearing High-Speed Flywheel Rotor System with Strong Gyroscopic Effect Proceedings of ISMB13  
Abstract: In high-speed flywheel energy storage system, the high ratio of the polar to transverse mass moments of inertia of the flywheel rotor and the high operating speed have a great effect on the stability of the flywheel rotor system, traditional decentralized controllers, such as PID, are very difficult to deal with such rotor instability due to significant gyroscopic effect. In order to realize effectively the stability of active magnetic bearings(AMBs) supporting flywheel rotor system with strong gyroscopic effect at high rotating speeds, a new method called modal decoupling control is proposed in this paper based on mathematic model of the AMBs high-speed rigid flywheel rotor system. The principle of the modal decoupling control is introduced, and its ability and effectiveness to control the dynamic characteristics of the AMBs high-speed rigid flywheel rotor system are numerically analyzed and compared with the traditional PID controller. It is shown that the modal decoupling control proposed can separately regulate each mode’ stiffness and damping through decoupling between the conical and the parallel modes, and obviously improve the dynamic behaviors and be capacity of stabilizing the AMBs high-speed rigid flywheel rotor system with strong gyroscopic effect in the high rotating speed region.
BibTeX:
@inproceedings{ISMB13_75,
  author = {Changsheng Zhu and Qi Zhang and Liangliang Chen},
  title = {Modal Decoupling Control for Active Magnetic Bearing High-Speed Flywheel Rotor System with Strong Gyroscopic Effect},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_75.pdf}
}
2012 Fleischer, E., Tröger, S. and Hofmann, W. Control of a Novel Integrated Radial-Axial Magnetic Bearing Proceedings of ISMB13  
Abstract: An important application area of magnetic bearings is machinery running in vacuum. Examples include vacuum pumps, flywheels and spin wheels for space craft. Here even small rotor losses can overheat the rotor because of the low heat transfer in vacuum. Therefore this project aims at realizing a magnetic suspension with minimal rotor losses. Thus a novel magnetic bearing structure has been developed. It can generate both radial and axial forces and employs a minimal number of poles and soft magnetic composites as iron core material for minimal losses. This paper presents the new bearing structure and a control strategy for it. The designed controller is verified in simulations and first experimental results are presented as well.
BibTeX:
@inproceedings{ISMB13_76,
  author = {Erik Fleischer and Stefan Tröger and Wilfried Hofmann},
  title = {Control of a Novel Integrated Radial-Axial Magnetic Bearing},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_76.pdf}
}
2012 Lembke, T. 1-Dof Bearing Arrangement with Passive Radial Bearings and Highly Efficient Integrated Electrodynamic Dampers, EDD Proceedings of ISMB13  
Abstract: This paper briefly describes a novel 1-DOF bearing arrangement with integrated passive electrodynamic dampers. A general problem with passive magnetic bearings is that sufficient damping in the radial direction is difficult to provide, without using additional rubber bushings or squeeze film dampers. Electrodynamic damping schemes are sometimes proposed, but they tend to have either weak or nonlinear properties, or they contribute to additional bearing instability in terms of negative stiffness. The proposed bearing arrangement is inherently stable in terms of positive stiffness in radial direction. For dynamic stability it comprehends short circuit coils with geometries that allow for both damping coefficient and cut-off frequency to be chosen at will. A discussion on alternative coil winding schemes and possible active control is done, and finally some preliminary test results from the first prototype are presented, indicating both a stable and a linear behavior.
BibTeX:
@inproceedings{ISMB13_77,
  author = {Torbjörn Lembke},
  title = {1-Dof Bearing Arrangement with Passive Radial Bearings and Highly Efficient Integrated Electrodynamic Dampers, EDD},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_77.pdf}
}
2012 Mitterhofer, H., Amrhein, W. and Grabner, H. Comparison of two- and four-pole rotors for a high speed bearingless drive Proceedings of ISMB13  
Abstract: Bearingless drives have found their way into several industrial applications such as pumps, fans and chemical process chambers. In contrast to these drives which run at speeds below 15.000rpm, the suitability of bearingless drives for high speed has first been demonstrated with a bearingless disk drive running up to 115.000rpm in previous works by the authors. This drive uses a permanent magnet rotor with a pole number of two in order to constrain iron losses and generate the highest rotor speed with a certain electrical frequency. Other design criteria such as the rotordynamic behaviour, the radial bearing force or the torque capacity, however, might benefit from a higher pole number. Therefore, this paper will present the comparison of a two-pole and a four-pole rotor for the use in a high speed bearingless drive.
BibTeX:
@inproceedings{ISMB13_78,
  author = {Hubert Mitterhofer and Wolfgang Amrhein and Herbert Grabner},
  title = {Comparison of two- and four-pole rotors for a high speed bearingless drive},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_78.pdf}
}
2012 Bauer, W. and Amrhein, W. Design Study of Air-Core Coil Winding Topologies for Bearingless Axial-Force/Torque Motors Proceedings of ISMB13  
Abstract: The Bearingless Axial-Force/TorqueMotor is a Lorentz-Force-Type actuator featuring a com-pact and integrated design using a special permanent magnet excitation system and a slotless air gap winding. The end-windings of the concentric air-core stator coils, shaped in circumferential rotor direction, provide active suspension forces in axial direction. The actuator unifies levitation force and drive torque generation in a single device unit sharing one common winding system. Especially for single-phase motor configurations, the resulting drive topology ensures the tilt sta-bilization of the rotor. In general, only a few air gap winding structures are suitable for proper polyphase drive torque generation without any negative side effects. The present article treats the drive torque and axial force generation mechanisms for Bearingless Axial-Force/Torque Motors and its influences regarding the appearance of tilt torques. As the radial drive stabilization is realized by multiple axial displaced passive magnetic ring bearings, the radial force generation due to a mismatch of the number of rotor pole pairs and the number of stator coils is also signif-icant for drive stability considerations. As conclusion, numerical simulations for different drive configurations will prove for the validity of the presented analytical design framework.
BibTeX:
@inproceedings{ISMB13_79,
  author = {Walter Bauer and Wolfgang Amrhein},
  title = {Design Study of Air-Core Coil Winding Topologies for Bearingless Axial-Force/Torque Motors},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_79.pdf}
}
2012 Beckerle, P., Schaede, H. and Rinderknecht, S. Model-Based Fault Detection on Active Magnetic Bearings by Means of Online Transfer-Factor Estimation Proceedings of ISMB13  
Abstract: This paper gives a deeper insight in model-based fault detection based on transfer-factor esti-mation on active magnetic bearings. The method aims at performing fault detection and diagnosis at minimal computational efforts. Hence, only a limited number of transfer-factors of the inves-tigated system are considered. These are used as features for the diagnosis and represented by the magnitude and the phase at frequencies showing strong deviations between the examined states. Previously modeled faults are diagnosed by an online-estimation of the transfer-factors and a comparison to reference values. Three algorithms for this fault detection method are de-scribed and compared in detail: Recursive Least Squares (RLS), Least Mean Squares (LMS) and Goertzel-algorithm. For the comparison of the algorithms, their convergence behavior and updat-ing rate are considered as well as the computational and implementation effort. Investigations on a test rig of a centrifugal pump in active magnetic bearings show that the RLS leads to slightly slower convergence with a higher computational effort than the LMS. The Goertzel-algorithm outperforms both in computational effort, but needs several samples for the computation and thus provides a lower updating rate. Based on their findings, the authors assess suitability of the algorithms for fault detection on active magnetic bearings.
BibTeX:
@inproceedings{ISMB13_8,
  author = {Philipp Beckerle and Hendrik Schaede and Stephan Rinderknecht},
  title = {Model-Based Fault Detection on Active Magnetic Bearings by Means of Online Transfer-Factor Estimation},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_8.pdf}
}
2012 Li, J., Xiao, K., Liu, K. and Hou, E. Mathematical Model of a Vernier Gimballing Momentum Wheel Supported by Magnetic Bearings Proceedings of ISMB13  
Abstract: Based on rotor dynamics and gyro dynamics, the mathematical model for a vernier gimballing momentum wheel supported by magnetic bearings was established to analyze the forces and torques generated by the wheel body . The static and couple unbalances of the structure are regarded as two main sources causing periodic disturbances to the stability of the system. Since the rotational speed of the rotor is high, the gyroscopic effect is also an important factor causing interference on the stability. Therefore, the effects of disturbances from above are considered to make the mathematical model be closer to the real state.
BibTeX:
@inproceedings{ISMB13_80,
  author = {Jiayi Li and Kai Xiao and Kun Liu and Eryong Hou},
  title = {Mathematical Model of a Vernier Gimballing Momentum Wheel Supported by Magnetic Bearings},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_80.pdf}
}
2012 Bahr, F., Melzer, M., Karnaushenko, D., Makarov, D., Karnaushenko, D., Mönch, J.I., Malane, D., Schmidt, O.G. and Hofmann, W. Flux Based Control of AMBs Using Integrated Ultra-Thin Flexible Bismuth Hall Sensors Proceedings of ISMB13  
Abstract: To increase stiffness and precise rotor positioning of active magnetic bearings (AMB), flux based control algorithms were suggested. However, the typical thickness of air gaps in AMBs is too small to apply conventional magnetic field sensors with a typical thickness of more than 500 µm. Furthermore, the curved surfaces of the sta tor poles require a mechanically flexible sensor design. Here, we propose a flexible Bismuth based Hall sensor with a total thickness of only 80 µm including encapsulation. After wiring th e sensors have a maximum height of 280 µm and could be mounted onto curved surfaces. T he fabricated sensors were characterized and the influence of size, temperature and bending radius on the Hall sensitivity was determined. On a proof-of-concept level we demonstrated the performance of the flexible magnetic field sensors to control an one-axis AMB with a levitating ball. Several algorithms using flux density measurements were tested and compared to conventional control strategies.
BibTeX:
@inproceedings{ISMB13_81,
  author = {Falk Bahr and Michael Melzer and Daniil Karnaushenko and Denys Makarov and Dmitriy Karnaushenko and Jens Ingolf Mönch and Dominic Malane and Oliver G. Schmidt and Wilfried Hofmann},
  title = {Flux Based Control of AMBs Using Integrated Ultra-Thin Flexible Bismuth Hall Sensors},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_81.pdf}
}
2012 Gruber, W., Briewasser, W., Rothböck, M., Schöb, R. and Amrhein, W. Bearingless Reluctance Slice Motors Proceedings of ISMB13  
Abstract: Bearingless permanent magnet motors are very compact and favorable for high speed designs. Especially the bearingless slice motor (using a permanent magnet excited rotor disc) features a mechanically simple and very cost effective fully magnetically levitated system by stabilizing some degrees of freedom by permanent magnetic reluctance forces. This work focuses on constructional possibilities to apply the slice rotor principle with its passive stabilization without any permanent magnetsin the rotor part. As a matter of fact, the permanent magnets are necessary and are therefore located in the stator. Possible stator compositions are outlined and separated into homopolar and heteropolar permanent magnet air gap flux types. The definition of performance parameters allows evaluating the operational behavior of the two considered bearingless reluctance slice motor types (one with hompolar and one with heteropolar air gap flux distribution). The composition, optimization and construction of a prototype are outlined in the last section. Measurements are conducted to show the proper functionality of the bearingless reluctance slice motor prototype.
BibTeX:
@inproceedings{ISMB13_82,
  author = {Wolfgang Gruber and Wolfgang Briewasser and Michael Rothböck and Reto Schöb and Wolfgang Amrhein},
  title = {Bearingless Reluctance Slice Motors},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_82.pdf}
}
2012 Kato, T., Takasaki, M., Mizuno, T. and Bleuler, H. Concept of Displacement Sensor Using Resonant Inductive Coupling Proceedings of ISMB13  
Abstract: This paper presents the concept of a novel displacement sensor based on resonant inductive coupling. Resonant inductive coupling uses two coils or LC circuits similarly to an electromagnetic induction. The electromagnetic induction, that is the principle of transformer, is also an interaction of magnetic fields in usually akilohertz-range. It is used for power transfer and operated with a small gap. A power transmissionwith rather larger gap is possible by using a megahertz-range resonance. Resonant inductive coupling is actively studied in the field of wireless power transfer recently. Meanwhile, some AMB systems need a displacement sensor operating with a large air gap. Thus, the resonant inductive coupling is applied to a displacement sensor. It can achieve high resolution (sub-mm) over a very large distance (10cm). In this paper, the principle of resonant inductive coupling is explained. Several basic results are shown, and these results are evaluated as a displacement sensor.
BibTeX:
@inproceedings{ISMB13_83,
  author = {Takaaki Kato and Masaya Takasaki and Takeshi Mizuno and Hannes Bleuler},
  title = {Concept of Displacement Sensor Using Resonant Inductive Coupling},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_83.pdf}
}
2012 Filatov, A. and Hawkins, L. Constant-Flux Edge Sensor Proceedings of ISMB13  
Abstract: A novel axial position sensor is presented. The sensor offers a unique combination of advantageous properties not found collectively in other axial position sensing solutions. These include ability to work in dusty environments and in many working fluids, low sensitivity to temperature as well as external electricaland magnetic fields, good linearity over a large displacement range, large intrinsic gain, easy integration into a machine, robustness to the variations in parametersof the external wiring, simplicity of the signal processing electronics, sufficient frequency bandwidth and a commonality of used elements with radial magnetic reluctance position sensors. This paper describes the operating principle, test procedure and test results of the constant-flux edge sensor in both single-sided and differential configurations. Presently the sensor has been successfully integrated into several commercial machines and extensively tested under various operating conditions.
BibTeX:
@inproceedings{ISMB13_84,
  author = {Alexei Filatov and Larry Hawkins},
  title = {Constant-Flux Edge Sensor},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_84.pdf}
}
2012 Mcmullen, P. and Hawkins, L. Long Term Backup Bearing Testing Results Proceedings of ISMB13  
Abstract: An energy storage flywheel was developed in 2005 to provide ride-through power for industrial UPS applications, and its application was expanded to provide regeneration power for mobile cranes. The flywheel, which operates in a vacuum, is supported by Active Magnetic Bearings (AMB) to minimize bearing losses, and has a high power motor/generator coupled to an efficient power conversion module. The flywheel can maintain energy for emergency use by holding at full speed or can be cycled up and down in speed to absorb and discharge energy rapidly. Over 400 Flywheel systems have been delivered and are operating in the field since product release. In addition to the AMB, the Flywheel system uses a backup bearing system to support the rotor; 1- when the system is not in operation, including shipping; 2- during low speed safe spin-downs when external power is disconnected, 3- during intermittent overload events (only expected in crane systems as a result of crane motion) and 4- during high speed spin-downs when system events/failures occur. Low speed spin-downs typically start at 4,000 rpm in crane systems and can happen multiple times a day, while UPS systems typically start at 6,000-8,000 rpm and may only happen once a year. Overloadevents in crane systems can happen at any speed in the operation range of 10,000 rpm to18,000 rpm and last for up to 5 seconds. The backup bearing system of every flywheel is tested with a series of backup bearing drop tests culminating with a drop and spin down from full speed. Additionally, several engineering flywheels have been used extensively for testing and development of the backup bearing system. The original system was capable of three 2.75 hour spin downs from 36,000 rpm and developed with the UPS system requirements in mind. Methodology and results for this test program were described in [1] and [2]. Recent testing has validated the system for use in crane system with added low speed spin-downs and momentary overload conditions at high speeds. In addition, incremental changes to the backup bearing system have resulted in extending the capability to eight 2.75 hour spin downs from 36,000 rpm for UPS applications. These changes are the result of continued analysis of backup bearing operation during spin-down. This ongoing test program is reported here – including a discussion of some of the test results.
BibTeX:
@inproceedings{ISMB13_85,
  author = {Patrick Mcmullen and Larry Hawkins},
  title = {Long Term Backup Bearing Testing Results},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_85.pdf}
}
2012 Shultz, R. and Yates, S. Landing Test Results for a 6 MW Motor Compressor and Auxiliary Bearing Systems for Corrosive Environments Proceedings of ISMB13  
Abstract: Auxiliary bearing landing tests have been conducted on a 6 MW vertical motor compressor. The corrosion resistant auxiliary bearing system for the motor compressor is a unique combination design with one auxiliary bearing of bushing type design and the other, a rolling element type design. The results of the landing test were good, with 5 landings completed and with the auxiliary bearings fit for further service. Corrosion resistant auxiliary bearing designs are described. Analysis methods and design considerations for auxiliary bearing systems are discussed.
BibTeX:
@inproceedings{ISMB13_86,
  author = {Richard Shultz and Simon Yates},
  title = {Landing Test Results for a 6 MW Motor Compressor and Auxiliary Bearing Systems for Corrosive Environments},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_86.pdf}
}
2012 Sun, Z., Zhao, J. and Yu, S. Nonlinear Nonparametric Identification of Magnetic Bearing System Based on Support Vector Regression Proceedings of ISMB13  
Abstract: The mathematical model of components in an active magnetic bearing system plays important roles in system designing and adjusting. The linearized models are widely applied; however, sometimes these models are not precise enough. In this paper, a nonlinear modeling method based on Support Vector Regression (SVR) is proposed. The proposed model treats the rotor acceleration as a nonlinear function of the rotor displacement, rotor velocity and the coil currents; the model parameters are determined by a training procedure based on observed samples, no mechanism, computational or empirical models are needed in the modeling procedure. The proposed method is validated by a series of experiments.
BibTeX:
@inproceedings{ISMB13_87,
  author = {Zhe Sun and Jingjing Zhao and Suyuan Yu},
  title = {Nonlinear Nonparametric Identification of Magnetic Bearing System Based on Support Vector Regression},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_87.pdf}
}
2012 Mo, N., Shi, Z., Zhou, Y. and Yu, S. Study on eddy current loss for active magnetic thrust bearings considering load variation, noise, and switching ripple currents Proceedings of ISMB13  
Abstract: Calculation of eddy current loss is an essential job in magnetic thrust bearings(MTBs) design in specific applications. In this work, a comprehensive model of eddy current loss in MTBs is presented. In this model, a fractional-order dynamic model is applied. The model parameters are estimated by heuristic optimization algorithm. The close loop model is constructed with the dynamic current stiffness and displacement stiffness. In this model, the load variation and sensor noise are considered. The eddy current loss brought by load variation and sensor noise is analyzed then. A pulse width modulation(PWM) switching power amplifiers(SPA) is also modeled and the switching ripple current(SRC) is calculated by finite element analysis(FEA). This result is applied to calculate the loss brought by SRC. According to the simulation results, it is concluded that the heat by SRC is dominant in common applications.
BibTeX:
@inproceedings{ISMB13_88,
  author = {Ni Mo and Zhengang Shi and Yan Zhou and Suyuan Yu},
  title = {Study on eddy current loss for active magnetic thrust bearings considering load variation, noise, and switching ripple currents},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_88.pdf}
}
2012 Kailasan, A., Jiang, W., Dimond, T., Sheffler, D. and Allaire, P. Design and analysis of the magnetic suspension system in an energy storage flywheel Proceedings of ISMB13  
Abstract: Over the past decade, there has been a rising need to develop more efficient, sustainable and environmentally friendly means of short term energy storage. Flywheel energy storage systems store kinetic energy by continuously spinning a compact rotor in a low-friction environment. Magnetic bearing suspension systems are desirable for this application since they significantly increase efficiency, reduce waste heat when operated in vacuum and reduce power requirements for the electronics. A demonstration flywheel energy storage test rig under development at the University of Virginia will use a five-axis active magnetic bearing support system. This paper discusses the design and analysis procedure of the flywheel magnetic suspension system. The magnetic suspension system will be controlled by a µ-synthesis controller, with an adaptive auto-balancing algorithm. Preliminary calculations are performed to determine the various design parameters such as nominal air gap, number of coil turns required, and stator/rotor diameter and thickness using linear magnetic circuit models. Finally, a 3-dimensional finite element analysis was conducted with commercial finite element software to verify the calculated design parameters. The flux path was visualized for both the thrust a nd radial magnetic bearings and important parameters such as load capacity, flux density, inductance and slew rate were calculated.
BibTeX:
@inproceedings{ISMB13_89,
  author = {Arunvel Kailasan and Wei Jiang and Timothy Dimond and David Sheffler and Paul Allaire},
  title = {Design and analysis of the magnetic suspension system in an energy storage flywheel},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_89.pdf}
}
2012 Fan, Y.-H., Lee, Y.-T., Chung, W.-C., Su, C.-X. and Lin, C.-H. Design of a Variable Structure Controller Based on the Force Estimator for a Single Active Magnetic Bearings Suspended Rotor System Proceedings of ISMB13  
Abstract: This study proposes a variable structure controller with a force estimator for a single active magnetic bearing suspended rotor system to eliminate the vibration associated with unbalance of mass. The model of a single active magnetic bearing suspended rotor system is build and a displacement and unbalancing force estimator of the system is established. A variable structure controller is also established according to the estimated force to decrease the influence of the unbalance force and increase the robust of the system. The experimental results showed that thevariable structure controller based on the force estimator for a single active magnetic bearing suspended rotor system was established successfully and has good accuracy.
BibTeX:
@inproceedings{ISMB13_90,
  author = {Yi-Hua Fan and Ying-Tsun Lee and Wei-Cheng Chung and Chong-Xian Su and Chung-Hsien Lin},
  title = {Design of a Variable Structure Controller Based on the Force Estimator for a Single Active Magnetic Bearings Suspended Rotor System},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_90.pdf}
}
2012 Kodochigov, N.G., Pobedonostsev, A.B., Ovchinnikov, V.F. and Drumov, I.V. Development and Testing of the Code and Procedure for Balancing the Flexible Vertical Electromagnetically Suspended Rotor Proceedings of ISMB13  
Abstract: It is known that the basic component of forces, which affects electromagnetic bearings (EMB), is centrifugal forces produced by the unbalanced rotor. The unbalanced forces must be reduced to the allowed level for the entire frequency band, including critical frequencies (GOST ISO 11342). For effective balancing, balancing weights shall be installed in accordance with actual rotor bending modes. Therefore, under research and development work carried out in JSC "Afrikantov OKBM" (Russia) activities are performed aimed at studying possibilities for balancing the flexible vertical rotor using EMBs in the machine. During this work, the special BALANS code and procedure for balancing the flexible rotor using EMBs were developed. At a small test facility having the vertical rotor [1, 2], experimental investigations were carried out to balance the flexible rotor using EMBs. Based on preliminary results, it is possible to balance the flexible vertical rotor using EMB without balancing the rotor in factory conditions. In 2011, JSC "Afrikantov OKBM" carried out work to balance the vertical rotor using electromagnetic suspension in the large test facility, i.e. in the Turbomachine (TM) Rotor Scale Model (RSM).
BibTeX:
@inproceedings{ISMB13_91,
  author = {N. G. Kodochigov and A. B. Pobedonostsev and V. F. Ovchinnikov and I. V. Drumov},
  title = {Development and Testing of the Code and Procedure for Balancing the Flexible Vertical Electromagnetically Suspended Rotor},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_91.pdf}
}
2012 Kodochigov, N.G., Drumov, I.V. and Malkin, S.A. Analysis and Experiment Results of Reactor Plant Turbomachine Rotor Model Investigations Proceedings of ISMB13  
Abstract: Analysis and experiment results of reactor plant turbomachine rotor model investigations are described. It is shown that application of linearization by feedback to produce the control algorithm allows system linearizing without use of bias current. The system linearized in this way has better dynamic qualities, particularly, the frequencies in rotor oscillation spectrum, which are different from rotation speed, are eliminated.
BibTeX:
@inproceedings{ISMB13_92,
  author = {N. G. Kodochigov and I. V. Drumov and S. A. Malkin},
  title = {Analysis and Experiment Results of Reactor Plant Turbomachine Rotor Model Investigations},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_92.pdf}
}
2012 Toh, C.S., Chen, S.L. and Juang, D.P. Development of a Ring-type Flywheel Battery System for Storage of Renewable Energy Proceedings of ISMB13  
Abstract: In this study, a small scale prototype of a ring-type flywheel battery system is designed and fabricated. The system consists of 5-DOF magnetic bearing and a built-in motor/generator. The magnetic bearing is of hybrid type, with passive axial magnetic bearing and active radial magnetic bearing. For the passive axial magnetic bearing, a pair of Halbach arrays of permanent magnets are arranged vertically to support the weight of rotor and flywheel. For the active radial magnetic bearing, a set of Halbach array is placed on the rotor side, which will correspond to a coil set on the stator side. The active magnetic bearing can produce both attraction and repulsion forces on the radial direction, depending on the direction of the coil currents. When driven by an active feedback control system operating in conjunction with a position sensor, the actuator force can be used to balance the lateral forces coupled from the passive axial magnetic bearing and to achieve stable levitation. In the radial magnetic bearing, the design of eight-pole and differential winding mode are applied, which can result in a linear force-current relation. Hence, the system can be modeled by a simple linear time-invariant system. For robustness, the controller is designed by integral sliding mode control (ISMC) to overcome the effects of uncertainty and to achieve good steady-state accuracy. Numerical simulation results verify the effectiveness of the controller. To further validate the efficiency of the proposed controller, the experiments of the prototype are also performed.
BibTeX:
@inproceedings{ISMB13_93,
  author = {Chow Shing Toh and Shyh Leh Chen and Dar Ping Juang},
  title = {Development of a Ring-type Flywheel Battery System for Storage of Renewable Energy},
  booktitle = {Proceedings of ISMB13},
  year = {2012},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb13/ismb13_submission_93.pdf}
}
2011 Vanek, C. and Worlitz, F. Experimentelle und theoretische Untersuchungen zum Rotorabsturz in Wälzlager Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Um eine Auslegung von Fanglagern durchzuführen ist es notwendig, die Belastungen dieser in den zu erwartenden Abwurfszenarien zu kennen. Da so ein chaotischer Vorgang schwer analytisch berechnet werden kann, ist es erforderlich, ein dynamische Simulationendurchzuführen. Der Beitrag soll einen Einblick in die experimentellen Arbeiten geben, welche zur Validierung eines solchen Berechnungsmodells nötig sind. Dabei soll vor allem auf einen Qualitätsfaktor eingegangen werden, welcher es ermöglicht verschiedene Fanglagerabwürfe mit Hilfe eines normierten Faktors zu vergleichen. Weiterhin wird auf den Einfluss des Auftreffwinkels des Rotors im Fanglager eingegangen, sowie einige Beispiele für die Anwendung des Qualitätsfaktors gegeben.
BibTeX:
@inproceedings{WMLT8_1,
  author = {C. Vanek and F. Worlitz},
  title = {Experimentelle und theoretische Untersuchungen zum Rotorabsturz in Wälzlager},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_1.pdf}
}
2011 Rudolph, J., Budig, P.-K. and Werner, R. Theoretische und praktische Betrachtungen zur Schwingungsdämpfung in permanentmagnetisch gelagerten Systemen Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Schwungradenergiespeichers können permanentmagnetische Lager eingesetzt werden. Diese arbeiten nahezu reibungsfrei und damit verlustarm. Technisch gesehen stellt solch ein Lager ein schwingfähiges Feder-Masse-System dar. Dies macht zusätzliche Maßnahmen zur Dämpfung notwendig. In dem vorliegenden Beitrag werden zunächst Möglichkeiten der Dämpfung rotierender permanentmagnetisch gelagerter Wellen vorgestellt und diskutiert. Aufgrund der getroffenen Aussagen wird ein permanentmagnetischer Dämpfungsmechanismus theoretisch sowie praktisch untersucht. Durch Magnete, die sich radial mit der Welle bewegen, wird in einer mit dem Gehäuse verbundenen Dämpfungsscheibe eine Spannung induziert. Durch sie werden in Abhängigkeit der elektrischen Leitfähigkeit entsprechende Wirbelströme hervorgerufen. Diese wiederum verursachen magnetische Felder, welche ihrer Ursache, der Schwingung, entgegen wirken. Die daraus resultierende Dämpfung kann durch die Betrachtung der magnetischen Kräfte oder aber den Energieerhaltungssatz beschrieben werden. Um eine bessere Wirkung zu erzielen, wurden Magnete in alternierender Polarisation angeordnet. Dadurch wurde die Änderung der Durchflutung der Dämpfungsscheibe pro Periode erhöht. Mit Hilfe eines Fall-Testes wird die Abhängigkeit der Dämpfungswirkung von der Anzahl der Magnetpole dargestellt. Für die Ausprägung nennenswerter Wirbelströme ist die Beschaffenheit der Scheibe von entscheidender Bedeutung. Sie muss möglichst gut elektrisch leitend sein und darf dabei keine ferromagnetischen Eigenschaften besitzen. Mit Hilfe eines Versuchslagers wurden die Zusammenhänge von Dicke und Material der Scheibe sowie der Abklingzeit einer angeregten Schwingung untersucht.
BibTeX:
@inproceedings{WMLT8_10,
  author = {J. Rudolph and P.-K. Budig and R. Werner},
  title = {Theoretische und praktische Betrachtungen zur Schwingungsdämpfung in permanentmagnetisch gelagerten Systemen},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_10.pdf}
}
2011 Paditz, M. Dimensionierung von Magnetlagern: Am Beispiel der Versuchsstandsmagnetlager für das IPM Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Abstract is not available
BibTeX:
@inproceedings{WMLT8_11,
  author = {M. Paditz},
  title = {Dimensionierung von Magnetlagern: Am Beispiel der Versuchsstandsmagnetlager für das IPM},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_11.pdf}
}
2011 Budig, P.-K. Betrachtungen zur Theorie und Anwendung magnetischer Lager Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Es wird eine Einführung in einige theoretische Grundlagen magnetischer Lager gegeben wie: Verluste, Dynamisches Betriebsverhalten, Ausführungsformen magnetischer Lager. Einige Anwendungen werden beschrieben, wie: Drehmomenten Messgerät für 140000 min-1, Ventilator Teststand, Kühlwasserpumpe in einem Kraftwerk, Lager für extrem große Lagerkräfte im Bereich der Lagerkräfte von 16000 bis 50000 Newton, Schwungradspeicher im Hochvakuum mit 45000 min-1 mit permanentmagnetischen Radiallagern.
BibTeX:
@inproceedings{WMLT8_12,
  author = {P.-K. Budig},
  title = {Betrachtungen zur Theorie und Anwendung magnetischer Lager },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_12.pdf}
}
2011 Dohnal, F. Increasing the external damping of a flexible rotor by periodic control Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: The influence of a periodic open-loop control operated in parallel to an existing closed-loop PID control is investigated on a rotor system supported by two radial active magnetic bearings. The transient behaviour of the rotor is studied numerically and first experimental results are shown to demonstrate the applicability of the method. It is highlighted that by tuning the periodic control properly it is possible to amplify artificially the external damping of the rotor system. This concept allows increasing the total external damping well beyond the stability margin of the closed-loop control cycle.
BibTeX:
@inproceedings{WMLT8_13,
  author = {F. Dohnal},
  title = {Increasing the external damping of a flexible rotor by periodic control },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_13.pdf}
}
2011 Katzschmann, M., Karolewski, D. and Schäffel, C. Entwicklung eines magnetisch geführten, planaren Direktantriebs Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Der Beitrag stellt ein magnetisches 6D Positioniersystem vor, welches auf einem an der IMMS GmbH entwickelten, planaren 3DDirektantriebssystem aufbaut. Die bisher eingesetzten Luftführungselemente werden im 6DSystem durch eine geregelte, aktive magnetische Führung ersetzt. Dies erfordert zusätzliche Sensorik zum Erfassen der vertikalen Lage. Zusätzliche Aktoren (Spulen) sind jedoch nicht nötig, da mit den bereits vorhandenen 6 Spulen alle Freiheitsgrade im gesamten Fahrbereich kontrolliert werden können. Um den Prozess der Auslegung einzelner Komponenten und der mechanischen Konstruktion optimal zu gestalten, sind umfangreiche Simulationen notwendig. Auf Basis der Simulationsergebnisse entsteht ein System, das die Vorteile des ursprünglichen, direktangetriebenen, planaren Positioniersystems mit denen eines magnetisch geführten Systems vereint.
BibTeX:
@inproceedings{WMLT8_14,
  author = {M. Katzschmann and D. Karolewski and C. Schäffel},
  title = {Entwicklung eines magnetisch geführten, planaren Direktantriebs},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_14.pdf}
}
2011 Bräuer, P., Bartscht, M. and Werner, R. Reduzierung des Bauraums bei einem aktiven dreipoligen Radialmagnetlager unter Verwendung von siebgedruckten Wicklungen Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Der nachhaltige Umgang mit der zur Verfügung stehenden Energie und Ressourcen wird in Zukunft einen immer höheren Stellenwert erlangen. Dabei werden Magnetlager eine zunehmende Rolle spielen. Sie arbeiten berührungsfrei und damit schmiermittelfrei, wodurch sie in Umgebungen, in denen es auf höchste Reinheit ankommt, eingesetzt werden können. Der Wartungsaufwand ist durch fehlenden mechanischen Abrieb reduziert und die Lebensdauer dadurch erhöht. Die Betriebskosten sind darüber hinaus geringer, da die auftretenden Verluste gerade im Bereich hoher Drehzahlen 1/5 bis 1/20 derer konventioneller Lager betragen. Es haben sich drei verschiedene Bauformen für magnetische Lager herauskristallisiert, welche sich in ihrem Aufbau, Verlusten, Einsatzmöglichkeiten oder auch ihrer Regelbarkeit unterscheiden. Der vom Aufbau her einfachste Typ ist das Unipolarmagnetlager. In diesem Beitrag soll dafür die Bauraumreduzierung im Bereich der Wicklung durch den Einsatz siebgedruckter Leiter, wie sie bereits seit längerem für Kleinantriebe in der wissenschaftlichen Diskussion sind [1], [2], untersucht werden. Das Siebdruckverfahren erlaubt es, besonders dünne flächige Leiter herzustellen, die aufgrund des Verhältnisses zwischen Querschnittsfläche und Oberfläche ein besseres Wäremeabgabevermögen aufweisen als Runddraht und daher Stromdichten von bis zu 100A/mm2 zulassen. Ziel ist es, bei gleicher Lagerkraft und gleichem Rotordurchmesser das Bauvolumen und damit die Masse des Lagers signifikant zu reduzieren. Erste Berechnungen zeigen, dass eine Reduzierung des Volumens um bis zu 50% denkbar ist. Technisch möglich ist darüber hinaus auch eine Integration von mittels Siebdruck hergestellten Sensoren zur Lagemesseung. Besonders günstig erscheinen in diesem Zusammenhang kapazitive Lagesensoren. Als Ergebnis sollen konstruktive Vorschläge für den Bau magnetischer Lager mit siebgedruckten Wicklungen gemacht werden.
BibTeX:
@inproceedings{WMLT8_15,
  author = {P. Bräuer and M. Bartscht and R. Werner},
  title = {Reduzierung des Bauraums bei einem aktiven dreipoligen Radialmagnetlager unter Verwendung von siebgedruckten Wicklungen },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_15.pdf}
}
2011 Hübner, N. Dimensionierung von hochtourigen Magnetlagern am Beispiel einer Magnetlagerspindel für 140.000 U/min Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Am Beispiel der Auslegung einer Magnetlager-spindel für 140.000 U/min sollen die Besonder-heiten bei der Dimensionierung hochtouriger Antriebe dargestellt werden. So ist es unerlässlich, dass neben der Festig-keitsauslegung auch besonderes Augenmerk auf die Rotordynamik gelegt wird. Dies bedingt, dass bezüglich des Wellenaufbaus der Spagat zwischen dem Platzbedarf der einzelnen auf der Welle befindlichen Komponenten und dem zum unterkritischen Betrieb zwingend nötige, biege-steife Aufbau umgesetzt wird. Es wird gezeigt durch welche Maßnahmen dies realisiert werden kann und wie die für den Be-trieb zwingend benötigten Komponenten wie Messsystem, Motor- und Lagerkomponenten sehr kompakt aufgebaut werden können. Hierzu musste zum Teil auf bisher für Magnetlager eher unkonventionelle Werkstoffe und Aufbauten zurückgegriffen werden. Ein weiteres Problem stellt die möglichst ver-koppelungsfreie Anbindung des Prüflings an die Magnetlagerspindel dar. Ebenfalls nicht unwesentlich sind die im Betrieb auftretenden Verluste durch Luftreibung und Ummagnetisierung. Diese Verluste werden vom Antriebsmotor gedeckt und müssen durch eine geeignete Kühlung abgeführt werden. Hierfür wurde auf eine kostengünstige Wasser-kühlung zurückgegriffen, welche eigentlich für die PC Kühlung vorgesehen ist. Die vorhandene Realisierung und die Leistungsfähigkeit dieser PC - Flüssigkühler wird in diesen Beitrag kurz erläutert.
BibTeX:
@inproceedings{WMLT8_2,
  author = {N. Hübner},
  title = {Dimensionierung von hochtourigen Magnetlagern am Beispiel einer Magnetlagerspindel für 140.000 U/min},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_2.pdf}
}
2011 Hübner, N. and Paditz, M. Erfahrungen bei der Anwendung passiver Radialmagnetlager in einem Schwungradenergiespeicher Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Von EAAT wurde ein magnetisch gelagertes Schwungradenergiespeichersystem entwickelt. Die Schwungradwelle läuft dabei im Vakuum. Um die zur Lagerung erforderliche Leistung gering zu halten, wurden passive, d.h. permanentmagnetische Radiallager eingesetzt. Die axiale magnetische Lagerung wurde durch ein aktives (elektromagnetisches) Axiallager realisiert. In diesem Beitrag soll auf den Aufbau des Systems und die Erfahrungen im Einsatz des Systems eingegangen werden. Einen Schwerpunkt bilden dabei die Verluste im System, sowie deren Abhängigkeiten von z.B. Temperatur und Rotordynamik.
BibTeX:
@inproceedings{WMLT8_3,
  author = {N. Hübner and M. Paditz},
  title = {Erfahrungen bei der Anwendung passiver Radialmagnetlager in einem Schwungradenergiespeicher},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_3.pdf}
}
2011 Neumann, H. and Worlitz, F. Modellierung und Simulation eines Kalman-Filters für aktive Magnetlager Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Die berührungsfreie magnetische Lagerung eines Rotors erfordert hinreichend schnelle und hochgenaue Reglereingriffe. Durch die räumlich getrennte Anordnung von Sensor und Sensorelektronik sind Störungen des analogen Messsignales in Form von Rauschen nicht zu vermeiden. Daher ist eine Signalfilterung notwendig. Diese wird im einfachsten Fall durch einen Butterworth-Filter realisiert. Eine weitere Möglichkeit ist die Verwendung eines Kalman- Filters, welcher neben der reinen Signalfilterung außerdem die Schätzung innerer, nicht messbarer Systemzustände ermöglicht.
BibTeX:
@inproceedings{WMLT8_4,
  author = {H. Neumann and F. Worlitz},
  title = {Modellierung und Simulation eines Kalman-Filters für aktive Magnetlager },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_4.pdf}
}
2011 Düsterhaupt, S. and Worlitz, F. Modellierung und Simulation der Zuverlässigkeit magnetgelagerter Maschinen Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Der Einsatz aktiver Magnetlager in Turbomaschinen der Kraftwerkstechnik ist durch extreme Prozessund Umgebungsbedingungen gekennzeichnet. Fertigungstoleranzen und der Einfluss spezifischer Betriebs- und Störszenarien auf die Komponenten eines Magnetlagerregelkreises führen zu Parameterstreuungen. Die Folge ist eine last- bzw. arbeitspunktabhängige Zuverlässigkeit der Lagerkomponenten. Die Auslegung aktiver Magnetlager soll um die Zuverlässigkeitsanalyse unter Berücksichtigung von komponentenspezifischen Nichtlinearitäten erweitert werden. Dabei werden mit Hilfe geeigneter Methoden im Gegensatz zur diskreten Herangehensweise die spezifischen Lagerparameter unscharf betrachtet. Mit Hilfe der Monte-Carlo-Simulation werden Teilversagenswahrscheinlichkeiten der Komponenten durch Abtastung des Zustandsraumes ermittelt und unter Anwendung der Fehlerbaumanalyse zu einer Versagenswahrscheinlichkeit des Gesamtsystems zusammengefasst. Es wird im Auslegungsprozess ermittelt, welche Komponenten des Regelkreises redundant/diversitär ausgeführt werden müssen.
BibTeX:
@inproceedings{WMLT8_5,
  author = {S. Düsterhaupt and F. Worlitz},
  title = {Modellierung und Simulation der Zuverlässigkeit magnetgelagerter Maschinen },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_5.pdf}
}
2011 Rothe, R. and Töpfer, H. Entwicklung einer Leistungselektronik für den Betrieb von Magnetlagern Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Im Rahmen der Zusammenarbeit mit der Hochschule Zittau Görlitz / IPM und Innotas Elektronik wurde eine Steuerelektronik speziell für den Betrieb von Magnetlagern entwickelt. Ausgehend von den bisherigen Erfahrungen entstand ein Konzept für eine Elektronik, bei der neue Schaltungstechniken zur Anwendung kamen. Dieses wurde schrittweise umgesetzt und es entstanden die Baugruppen Controllerboard, Leistungssteller in Form einer PWM Endstufe und Stromversorgung. Es wurde eine komplette Einheit, bestehend aus 2 Controllerboards und 7 Leistungsstellern, für einen Versuchsstand am IPM aufgebaut.
BibTeX:
@inproceedings{WMLT8_6,
  author = {R. Rothe and H. Töpfer},
  title = {Entwicklung einer Leistungselektronik für den Betrieb von Magnetlagern },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_6.pdf}
}
2011 Weidenmüller, F. and Lehmann, R. Digitale Magnetlagerregelung Mathematische Grundlagen, Aufbau des digitalen Reglers und praktische Erfahrungen Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Magnetische Lager sind strukturinstabil. Sie benötigen in mindestens einer Achse eine aktive Lagerstelle. Es sind analoge oder digitale Regler notwendig, den Rotor in seiner Position zu halten. Der erste Teil des Beitrags beschäftigt sich mit den mathematischen Grundlagen der Magnetlagerregelung. Ausgehend aus dem Blockschaltbild sowie den Filter- und Reglergleichungen in der Laplace Ebene erfolgt die Herleitung der Gleichungen in zeitdiskreter Form. Die dafür notwendigen Gleichungen werden aufgestellt und in die Struktur des allgemeinen IIR-Filters überführt. Anschließend folgt die Transformation vom statorfesten in das rotorfeste Koordinatensystem für die 3-phasige Maschine. Ein struktureller Ablaufplan des Programms soll die Möglichkeit der speicheroptimierten Implementierung in den Prozessrechner zeigen. Der zweite Teil des Beitrags beginnt mit Erfahrungen im praktischen Aufbau einzelner Komponenten und endet mit Hinweisen zur Inbetriebnahme sowie einer Gegenüberstellung von Vor- bzw. Nachteilen analoger und digitaler Regler.
BibTeX:
@inproceedings{WMLT8_7,
  author = {F. Weidenmüller and R. Lehmann},
  title = {Digitale Magnetlagerregelung Mathematische Grundlagen, Aufbau des digitalen Reglers und praktische Erfahrungen},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_7.pdf}
}
2011 Rottenbach, T. and Worlitz, F. Revision der magnetgelagerten Pumpe nach Langzeiteinsatz im Braunkohlenkraftwerk Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Im Rahmen eines Forschungsprojektes wurde eine konventionell gelagerte Kühlwasserdruckerhöhungspumpe auf vollständig aktive Magnetlagerung umgerüstet und im Zwischenkühlkreislauf eines 500-MW-Kraftwerksblockes als Demonst-rationsanlage eingebaut und getestet. Ziel war es, die Eignung von Magnetlagern für den Einsatz an Turbomaschinen im Kraftwerksbetrieb nachzuweisen [1]. Im Anschluss an die Inbetriebnahmephase erfolgte der Langzeiteinsatz als Betriebspumpe [2]. Nach einer ca. dreieinhalbjährigen Laufzeit wurde die Pumpe einer Revision unterzogen. Dabei wurde der Zustand der Pumpe und speziell der Lagerkomponenten begutachtet. Erforderliche, zustandsabhängig durchzuführende Reparatur- und Wartungsarbeiten der Magnet- und Fanglagerkomponenten sollten den Weiterbetrieb der Pumpe im Kraftwerk sicherstellen. Aus festgestellten Mängeln an Einzelkomponenten sowie aufgetretenen Schwierigkeiten bei der Demontage z. B. infolge Korrosion waren Maßnahmen zu deren Vermeidung abzuleiten. Zudem lassen sich daraus Rückschlüsse für die konstruktive Gestaltung künftiger Anwendungen, einzusetzender Materialien und Anforderungen z. B. an die Wellendichtung ziehen. Der Beitrag gibt einen Einblick in die Erfahrungen und den Wissenszuwachs, die während der Revision der aktiv magnetgelagerten Pumpe gesammelt wurden.
BibTeX:
@inproceedings{WMLT8_8,
  author = {T. Rottenbach and F. Worlitz},
  title = {Revision der magnetgelagerten Pumpe nach Langzeiteinsatz im Braunkohlenkraftwerk},
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_8.pdf}
}
2011 Fleischer, E. and Hofmann, W. Auslegung eines Asynchronversuchsmotors mit Massivläufer für ein Hochgeschwindigkeitsmagnetlager Proceedings of Workshop on Magnetic Bearing Technology 8  
Abstract: Im Rahmen des DFG–Projekts „Verlustarme magnetische Lagerung“ werden an einem Hochgeschwindigkeitsmagnetlager Untersuchungen zu den Rotorverlusten durchgeführt. Da die magnetische Lagerung und der Antrieb eine Einheit bilden, wird zur erfolgreichen Durchführung von Auslaufversuchen eine Antriebsmaschine mit minimalen Schleppverlusten benötigt. Aufgrund der Eignung für hohe Drehzahlen und des geringen Fertigungsaufwandes wurde dafür ein Asynchronmotor mit massivem Läufer und axialen Schlitzen ausgewählt. Im folgenden wird die Auslegung dieses Versuchsmotors für einen Betrieb im Vakuum vorgestellt.
BibTeX:
@inproceedings{WMLT8_9,
  author = {E. Fleischer and W. Hofmann},
  title = {Auslegung eines Asynchronversuchsmotors mit Massivläufer für ein Hochgeschwindigkeitsmagnetlager },
  booktitle = {Proceedings of Workshop on Magnetic Bearing Technology 8},
  year = {2011},
  url = {http://www.magneticbearings.org/wp-content/publications/wmlt8/wmlt8_9.pdf}
}
2010 v. Vuuren, P., v. Schoor, G. and Venter, W. Robustness Analysis of a Self-Sensing AMB by Means of µ-Analysis Proceedings of ISMB12  
Abstract: The stabilitymargin of a two degree-of-freedomself-sensing AMB is estimated bymeans of µ-analysis. The specific self-sensing algorithm implemented in this study is the direct current measurement (DCM) method. Detailed black-box models are developed for the main subsystems in the AMB by means of discrete-time system identification. Suitable excitation signals are generated for system identification in cognisance of frequency induced nonlinear behaviour of the AMB. Novel graphs that characterize an AMB’s behaviour for input signals of different amplitudes and frequency content are quite useful in this regard. In order to obtain models for dynamic uncertainty in the various subsystems (namely the power amplifier, self-sensing module and AMB plant), the identified models are combined to form a closed-loop LTI model for the self-sensing AMB. The response of this closed-loop model is compared to the original AMB’s response and models for the dynamic uncertainty are empirically deduced. Finally, the system’s stability margin for the modelled uncertainty is estimated by means of µ-analysis. The resultant µ-analyses show that self-sensing AMBs are rather sensitive for variations in the controller and the self-sensing module.
BibTeX:
@inproceedings{ISMB12_10,
  author = {P. v. Vuuren and G. v. Schoor and W.C. Venter},
  title = {Robustness Analysis of a Self-Sensing AMB by Means of µ-Analysis},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_10.pdf}
}
2010 Hou, E. and Liu, K. Study on Dynamic Characteristics of Magnetic Suspending Flywheel Based On Finite Element Method Proceedings of ISMB12  
Abstract: The configuration and principle of a magnetic suspending flywheel which was supported by hybrid magnetic bearings were introduced. A 3D finite element model of flywheel rotor was established by ANSYS10.0. The initial several vibration modes and frequencies were got in static state. The results of rigid vibration were compared with the theoretical ones, which proved the reasonability of the finite element model. The influence of radial and axial bearing stiffness and centrifugal prestress to dynamic characteristics was studied. The findings will be useful for the selection of control parameters and the optimization of the system.
BibTeX:
@inproceedings{ISMB12_101,
  author = {Eryong Hou and Kun Liu },
  title = {Study on Dynamic Characteristics of Magnetic Suspending Flywheel Based On Finite Element Method },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_101.pdf}
}
2010 Cai, J., Deng, Z., Qi, R. and Liu, Z. Modeling of Bearingless Switched Reluctance Motor Based On Artificial Neural Network Proceedings of ISMB12  
Abstract: Accurately calculating and modeling of the flux linkage characteristics is a critical step in design and analysis of optimal control strategies for Bearingless Switched Reluctance Motor (BSRM). But due to the highly nonlinear characteristics of BSRM, it is very difficult to derive a comprehensive mathematical model to satisfy the overall characteristics of the machine. To overcome this problem, in this paper, an edge finite element method (EFE) based 3-D FEM and a new enhanced incremental energy method were utilized for calculating the flux linkage characteristics; using the calculated flux data, an adaptive neural fuzzy inference system (ANFIS) based flux model was developed. Simulation results are presented and compared with the analytical nonlinear modeling method, which verified that the proposed model can modeling the BSRM more accurately and adaptively.
BibTeX:
@inproceedings{ISMB12_103,
  author = {Jun Cai and Zhiquan Deng and Ruiyun Qi and Zeyuan Liu },
  title = {Modeling of Bearingless Switched Reluctance Motor Based On Artificial Neural Network },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_103.pdf}
}
2010 Li, H., Cao, G., Qiu, H. and Pan, J. Nonlinear Modeling and Co-Simulation with MATLAB, ADAMS and ANSYS for Active Magnetic Bearings Proceedings of ISMB12  
Abstract: A newnonlinear model for AMBs is developed and co-simulation is carried out by combining ADAMS, MATLAB and ANSYS. The prototype model of AMBs system is obtained and can be used for co-design. The 1-degree-of-freedom (1-DOF) static levitation of axial magnetic bearing and the 2-degree-of-freedom (2-DOF) static levitation of radial magnetic bearing are respectively realized. The 5-degree-of-freedom (5-DOF) AMBs linear system has also been levitated steady and the system has a good control performance. Simulation results verify the correctness of the AMBs model which is based on the virtual prototype technology.
BibTeX:
@inproceedings{ISMB12_104,
  author = {Hanyi Li and Guangzhong Cao and Hong Qiu and Jianfei Pan },
  title = {Nonlinear Modeling and Co-Simulation with MATLAB, ADAMS and ANSYS for Active Magnetic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_104.pdf}
}
2010 Huang, C., Zhou, J. and Guo, Q. The Dynamic Characteristic of Rotor-Active Magnetic Bearings System on Flexible Base subjected to Base Vibration Proceedings of ISMB12  
Abstract: Magnetic bearings are the core and key technology of a multi-electric engine. The aero engine will have no lubrication system, less weight, high reliability and efficiency, and low maintenance costs if magnetic bearings be used instead of rolling bearings. Many papers had been published research results on rotor-AMB system on ground based support, which can not better describe the real condition of aero engine. This paper models the rotor-active magnetic bearing (AMB) system hanging from a cantilever beam to simulate the effect of flexible wing on the rotor dynamic characteristics. Besides, in order to observe the effect of wing vibration on the engine rotor, the beam’s free end receives excitation and the frequency response of rotor is analyzed. From simulation analysis result, it can be found that change of hanging position results in change of the base spatial modal properties (Mand K). Consequently, the modal frequency of some rotor shapes changes irregularly. Under the same excitation conditions, imposed on the flexible base (as opposed to a rigid foundation), the rotor frequency response slightly decreased except in the beam type modal frequencies.
BibTeX:
@inproceedings{ISMB12_105,
  author = {Chunxin Huang and Jin Zhou and Qintao Guo },
  title = {The Dynamic Characteristic of Rotor-Active Magnetic Bearings System on Flexible Base subjected to Base Vibration },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_105.pdf}
}
2010 Mo, N., Fu, X., Zhou, Y. and Yu, S. Study on EMI of Power Amplifiers in Active Magnetic Bearing Systems Proceedings of ISMB12  
Abstract: The problem of electromagnetic compatibility in active magnetic bearing systems is studied, and the aspect of this specific problem is illustrated. The main concern of this work is electromagnetic inference caused by power amplifiers. The modeling methodology of power amplifiers is studied, and a nonideal simulation model with essential distributed parameters considered is obtained. Simulation work is carried out to reveal the mechanisms of the electromagnetic inference signal generation. The results validate the modeling and indicate potential measures to reduce electromagnetic inference of power amplifiers.
BibTeX:
@inproceedings{ISMB12_106,
  author = {Ni Mo and Xiaoming Fu and Yan Zhou and Suyuan Yu },
  title = {Study on EMI of Power Amplifiers in Active Magnetic Bearing Systems },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_106.pdf}
}
2010 Reisinger, M., Grabner, H., Silber, S., Amrhein, W., Redemann, C. and Jenckel, P. A Novel Design of a Five Axes Active Magnetic Bearing System Proceedings of ISMB12  
Abstract: In prospective applications for active magnetic bearings, apart from performance and reliability, system costs are a major concern. The design of the proposed five axes active magnetic bearing system allows low manufacturing and assembly costs. Based on a simple modification, a radial bearing of heteropolar or homopolar type can produce radial as well as axial forces. Radial and axial forces are generated by the same set of permanent magnets and coils. This simplifies power electronics design considerably. Simulation and experimental results demonstrate the characteristics of the proposed design.
BibTeX:
@inproceedings{ISMB12_108,
  author = {Martin Reisinger and Herbert Grabner and Siegfried Silber and Wolfgang Amrhein and Christian Redemann and Peter Jenckel},
  title = {A Novel Design of a Five Axes Active Magnetic Bearing System },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_108.pdf}
}
2010 Sun, F. and Oka, K. Characteristics Analysis of Magnetic Suspension Mechanism with Variable Flux Path Control Proceedings of ISMB12  
Abstract: This paper proposes a magnetic suspension system using a disk-type permanent magnet and a rotary actuator. In this suspension system, the suspension force is controlled by a variable magnetic flux path mechanism where the flux path is changed by varying the angle of the magnet. This system has the characteristics of semi-zero suspension force, variable magnetic poles, and energy-saving suspension. In this paper, the variable flux path control method and an experimental prototype are introduced. Based on the results of the basic experiments, numerical simulation, and suspension experiments, the characteristics of the proposed mechanism are analyzed.
BibTeX:
@inproceedings{ISMB12_11,
  author = {Feng Sun and Koichi Oka},
  title = {Characteristics Analysis of Magnetic Suspension Mechanism with Variable Flux Path Control },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_11.pdf}
}
2010 Jastrzebski, R.P., Hynynen, K.M. and Smirnov, A. Uncertainty Set, Design and Performance Evaluation of Centralized Controllers for AMB System Proceedings of ISMB12  
Abstract: In this paper an industrially recognized modal control approach, a linear-quadratic-Gaussian (LQG) control, and an H8 control designs are compared using automated weights tuning based on a genetic algorithm. The robust stability analysis is carried out based on the uncertainty set, which comprises parametric and nonparametric uncertainties. The uncertainty set is updated to be compliant with the measured frequency responses of the test rig. The studied combination of the uncertainties proves too conservative for the direct application in the H8 control synthesis. However, a robust stability of the controllers synthesized using the nominal plant can be verified using µ-analysis and the very uncertainty set that cannot be used for the controller design directly. It is demonstrated that for the rigid rotor without strong gyroscopic coupling all of the control approaches result in a similar performance. For the more slender rotor with an additional disc and the dynamics dependent on the rotational speed the best results are achieved by the LQG and H8 controllers. When no gain scheduling is applied, the modal control results in the unstable system.
BibTeX:
@inproceedings{ISMB12_110,
  author = {Rafal P. Jastrzebski and Katja M. Hynynen and Alexander Smirnov},
  title = {Uncertainty Set, Design and Performance Evaluation of Centralized Controllers for AMB System },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_110.pdf}
}
2010 Hofer, M., Staffler, W. and Schrödl, M. Sensorless Control of a Three Phase Radial Active Magnetic Bearing Proceedings of ISMB12  
Abstract: This paper presents results of a three phase radial active magnetic bearing architecture combined with a sensorless position control algorithm. Therefore the three coil bearing structure is utilized by a three phase voltage source drive inverter. To reduce bias current consumption permanent magnet bias fluxing is used and iron losses are reduced by gaining homopolar architecture. The sensorless position detection algorithm and the control architecture are presented. Experimental results confirm the sensorless concept by measurements and quality measures for the sensorless method are investigated to show the limits of operation.
BibTeX:
@inproceedings{ISMB12_112,
  author = {Matthias Hofer and Wolfgang Staffler and Manfred Schrödl},
  title = {Sensorless Control of a Three Phase Radial Active Magnetic Bearing },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_112.pdf}
}
2010 Nguyen, Q.D., Shimai, N. and Ueno, S. Control of 6 Degrees of Freedom Salient Axial-Gap Self-Bearing Motor Proceedings of ISMB12  
Abstract: This paper introduces the control of a 6 degree of freedom (DOF) axial-gap selfbearing motor (AGBM), in which a hybrid active magnetic bearing system is in charge of 4 DOFs for radial levitation in x and y directions, and a salient type permanent magnet AGBM takes charge of 2 DOFs for rotation and axial motion in z direction. First, structure and working principle of the hybrid magnetic bearing and the AGBM are analyzed. The radial force equations of the hybrid magnetic bearing, and the electromagnetic torque equation as well as the axial force equation of the AGBM are then given. Finally,control structure is derived to confirm that the complete non-contact levitation can be realized by the simple construction and control system. To demonstrate the proposed technique, a salient 2-pole AGBM has been constructed and tested. The experimental results confirm that the AGBM drive performs well when its rotor is completely levitated.
BibTeX:
@inproceedings{ISMB12_113,
  author = {Quang Dich Nguyen and Nobukazu Shimai and Satoshi Ueno},
  title = {Control of 6 Degrees of Freedom Salient Axial-Gap Self-Bearing Motor },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_113.pdf}
}
2010 Zhou, D. and Zhu, C. Failure Mechanism of Improved Three-Level Power Amplifier for Active Magnetic Bearings Proceedings of ISMB12  
Abstract: In switching power amplifiers used in active magnetic bearings, three-level modulation technique is commonly used to reduce the current ripple of switching power amplifiers, so as to improve the performance of active magnetic bearing system. In our research, it is found that when a modified three-level PWM modulation technique was used in the switching power amplifiers, the output current waveform of the three-level PWM power amplifier was inconsistent with the theoretical waveform sometimes. At the same switching frequency, the current ripple of the modified three-level PWM power amplifier was much bigger than the theoretical value. The failure phenomenon is introduced and the failure mechanism of the modified three-level PWM power amplifier is theoretically analyzed for different carrier waves based on the analysis of the modified three-level PWM modulation technology in this paper. It is found that the deviation of bias voltage setting in the modified three-level PWM circuit results in its failure, and the failure mechanism is different for different carrier waves. Simulation and experimental results are in good agreement with the theoretical analyses. Finally, some suggestions about avoiding the failure of the modified three-level PWM power amplifier are proposed.
BibTeX:
@inproceedings{ISMB12_114,
  author = {Dan Zhou and Changsheng Zhu },
  title = {Failure Mechanism of Improved Three-Level Power Amplifier for Active Magnetic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_114.pdf}
}
2010 Zhang, Y., Liu, S., Guan, Y. and Yan, Y. Design and Optimization of Axial Position Sensing System in Maglev Blood Pump Proceedings of ISMB12  
Abstract: The position sensing system is one of the most important parts in maglev artificial heart pump. This paper describes a newly developed axial position sensor system. The position sensing system is designed to be combined with the radial permanentmagnetic bearing and used for the control of the axial active magnetic bearing. The rotor ring of the radial magnetic bearing is used as field source, which shortens the rotor and saves space for maglev blood pump design. Linear hall sensor is selected due to its low cost and miniature size. The principle of the position sensing system is based on the analysis of the magnetic field of the permanent magnetic bearing and the sensor module is designed via finite-element analysis to optimize sensitivity and accuracy of the measured signals. An applied primary amplifier circuit for the position sensing is designed and its performance is tested. The experimental results demonstrate that the position sensing system has a satisfactory performance and is effective for axial control.
BibTeX:
@inproceedings{ISMB12_115,
  author = {Yunpeng Zhang and Shuqin Liu and Yong Guan and Youpeng Yan },
  title = {Design and Optimization of Axial Position Sensing System in Maglev Blood Pump },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_115.pdf}
}
2010 Jan, Z., Bronislaw, T. and Dawid, W. Discretization Mesh Design for a Magnetic Bearing in the 3D Field Analysis Proceedings of ISMB12  
Abstract: In this paper, nonsymmetrical 12-pole (AMB12) magnetic bearings are analyzed. 3D Finite Element Method (FEM) was used for the magnetic field computations and nonlinear boundary problem was investigated. Discretization process is described for the AMB modeling, [5]. Research applies adaptation meshing method with the aid of high-order finite elements.
BibTeX:
@inproceedings{ISMB12_117,
  author = {Zimon Jan and Tomczuk Bronislaw and Wajnert Dawid},
  title = {Discretization Mesh Design for a Magnetic Bearing in the 3D Field Analysis },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_117.pdf}
}
2010 Kagamiishi, T., Rachmanto, B., Hiura, Y. and Nonami, K. Optimized Design for AMB Based Flywheel Energy Storage and Power Conversion Systems Proceedings of ISMB12  
Abstract: A flywheel energy storage system (FESS) works by accelerating a flywheel to a very high speed and maintaining the energy in the system as rotational energy. An Active magnetic bearing flywheel (AMB-FW) has many advantages such as low friction loss, short time distance, and no chemical waste. They can be expected to replace lead acid batteries as an energy resource. Our research group aimed to construct a new static FESS by using AMB-FW. The charge and discharge unit (CDU) that controls the charge and discharge energy dominates the static system. This paper reports on the result of creating and controlling CDU through simulations and experiments
BibTeX:
@inproceedings{ISMB12_118,
  author = {Takahiro Kagamiishi and Budi Rachmanto and Yuki Hiura and Kenzo Nonami},
  title = {Optimized Design for AMB Based Flywheel Energy Storage and Power Conversion Systems },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_118.pdf}
}
2010 Rachmanto, B., Nonami, K., Hiura, Y. and Kagamiishi, T. Variable Bias Type AMB Flywheel Powered Electric Vehicle without any Touchdown against Load Disturbance Proceedings of ISMB12  
Abstract: This paper deals with a stabilization control of active magnetic bearings (AMBs). Conventionally, zero bias method was chosen in stabilization control for its advantage in minimizing stabilization energy. However stiffness of the method is low, and touchdown may occur when the vehicle moves at high acceleration rate. We introduce bias current in fixed or variable rate using generalized switching rule for zero/nonzero bias control with regards to current saturation. Depending on external disturbance, it acts as a zero bias controller or bias controller.
BibTeX:
@inproceedings{ISMB12_119,
  author = {Budi Rachmanto and Kenzo Nonami and Yuki Hiura and Takahiro Kagamiishi},
  title = {Variable Bias Type AMB Flywheel Powered Electric Vehicle without any Touchdown against Load Disturbance },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_119.pdf}
}
2010 HIijikta, W., Mamiya, T., Shinshi, T. and Takatani, S. Cost-effective Magnetic Bearing System Using a Single-Use Magnet-Less Rotor for an Extracorporeal Centrifugal Blood Pump Proceedings of ISMB12  
Abstract: In the field of rotary blood pumps, contactless support of an impeller by a magnetic bearing has been identified as a promising method to reduce blood damage and enhance the durability. We have developed a two-degrees-of-freedom controlled magnetic bearing system without any permanent magnet in the impeller, so that a single-use pump head of an extracorporeal centrifugal blood pump could be manufactured more easily at a low cost. A prototype blood pump with the magnetic bearing realized stable levitation and contactless rotation of the impeller. The run-out of the impeller position from 1,000 rpm to 3,000 rpm was less than 70 µm (3?) in the radial controlled directions. The total power consumption of the magnetic bearing was less than 1 W at the same rotational speeds. The pump could yield a flow rate of 5 L/min against a head pressure of 590 mmHg (78.7 kPa) at the speed of 4,000 rpm, which provided sufficient performance for an extracorporeal circulation support.
BibTeX:
@inproceedings{ISMB12_12,
  author = {Wataru HIijikta and Taichi Mamiya and Tadahiko Shinshi and Setsuo Takatani},
  title = {Cost-effective Magnetic Bearing System Using a Single-Use Magnet-Less Rotor for an Extracorporeal Centrifugal Blood Pump },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_12.pdf}
}
2010 Wang, X. and Fang, H. The Calculation of the Centripetal Force of a Magnetic Suspension System using ANSYS Proceedings of ISMB12  
Abstract: The centripetal force of a magnetic suspension disc is compared by experimental results, calculating by use ANSYS and calculating by Force-Balance method. Research results show that centripetal force of a magnetic suspension system is related to the structure and control system. For the control currents of the magnetic suspension disc are not known in advance, thus it is impossible to directly adopt ANSYS to calculate centripetal force, the control currents of the magnetic suspended disc measured by experiments is used to form ANSYS calculation model. The calculate results using ANSYS match well with the experimental measurements. The calculation of Force-Balance method is not applicable to calculate centripetal force of the magnetic suspension system. The process of the calculation is introduced and the error in the calculation is analyzed as well.
BibTeX:
@inproceedings{ISMB12_121,
  author = {Xiaoguang Wang and Huijuan Fang },
  title = {The Calculation of the Centripetal Force of a Magnetic Suspension System using ANSYS },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_121.pdf}
}
2010 Zhu, Y. and Xu, L. Influence of Elastic Buffer on Rotor Drop Dynamic Response Proceedings of ISMB12  
Abstract: In an active magnetic bearing (AMB) system, the rolling-element catcher bearings (CBs) are indispensable to protect the magnetic bearing rotor and stator. This paper introduces a new structure with elastic buffers located on the rotor. And numerical analysis for a rotor drop on CBs using detailed CB model on the basis of Hertz contact theory are presented. The backward whirl of the rotor, which may lead to the destructive damage of the machinery, has been analytically predicted when the system without elastic buffers. The displacements of the sleeve and rotor and also the contact force between the sleeve and the inner-race of the back-up bearing have been computed for various buffer stiffness and damping parameters. Furthermore, elastic buffer design guides based on the simulation results are presented.
BibTeX:
@inproceedings{ISMB12_122,
  author = {Yili Zhu and Longxiang Xu },
  title = {Influence of Elastic Buffer on Rotor Drop Dynamic Response },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_122.pdf}
}
2010 Song, C. and Hu, Y. Active Vibration Isolation of Multiple Degree-of-Freedom System Based on the Minimization of the Output Force Control Strategy Proceedings of ISMB12  
Abstract: Vibration isolation technology has been widely used to reduce the vibration transmission from the machinery to the foundation in many different engineering systems. Magnetic suspension vibration isolation technology is an excellent active isolation technology, which has some useful characteristics, such as non-contact, high response frequency, high reliability and long life-span. Hence, the magnetic suspension isolator is designed. The electromagnetic force of the magnetic suspension active isolator is measured in advance by experiment. Multiple degrees of freedom (DOFs) vibration isolation system supported by magnetic suspension isolators and springs is established. The dynamical and state equations of the system are formulated. A control algorithm and the value function of active vibration isolation based on force transmissibility are proposed. The control model based on the control algorithm is established. Output force responses of the active vibration isolation system and passive one under same excitation are simulated. The simulation results indicate the active system possessed much better effect on vibration isolation. Comparing with passive system, the force transmissibility is reduced by 2dB-3dB in low-frequency stage, especially around resonance frequency, the transmissibility is reduced by 10dB-18dB. In order to test the reliability of the active system and control algorithm, an experimental platform is carried out. Experiment results show that the force transmissibility is reduced by 10dB-15dB around resonance frequency. The research indicates that experimental results are found to be in good agreement with simulated results.
BibTeX:
@inproceedings{ISMB12_123,
  author = {Chunsheng Song and Yefa Hu },
  title = {Active Vibration Isolation of Multiple Degree-of-Freedom System Based on the Minimization of the Output Force Control Strategy },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_123.pdf}
}
2010 He, Y., Hu, Y. and Wang, Z. Compact AMB-flywheel structure design and support control system Proceedings of ISMB12  
Abstract: In this paper, an AMB-flywheel energy storage system with 3-electromagnets is developed for minimizing flywheel size and reducing the production cost. The system description and dynamics characteristic of the AMB-flywheel system are discussed. Based on analyzing the dynamic model of the magnetic flywheel disc, the digital control system based on TMS320F2812 via using integral-separated PID control algorithm is designed, which realize the stable suspension of magnetic suspension platform.
BibTeX:
@inproceedings{ISMB12_124,
  author = {Yong He and Yefa Hu and Ziyan Wang },
  title = {Compact AMB-flywheel structure design and support control system },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_124.pdf}
}
2010 Qian, J., Wang, X., Tian, F. and Li, W. Application of Power Amplifier OPA544 in Active Magnetic Bearing Control System Proceedings of ISMB12  
Abstract: Adopt device power amplifier OPA544 to amplify the output load current in order to achieve the system's current increase. According to the completed mechanical analysis and the design of this specific active magnetic system, the controlling model was designed and a PID controlling strategy was selected to achieve a system simulation utilizing the whole module’s parameters. To control the suspension, a PID controlling circuit was designed to attain the full current necessary for maintaining lift. The use of two electronic OPA544 chips allows for push-pull power amplifier control, achieving the establishment of active magnetic plate dynamic equilibrium, as well as better system stability. Experimental data from the study supported the simulation. The system designed represents a practical model based on experimental data. These methods could be used as a reference for power amplifier component selection among similar systems.
BibTeX:
@inproceedings{ISMB12_125,
  author = {Jing Qian and Xiping Wang and Feng Tian and Wanpeng Li},
  title = {Application of Power Amplifier OPA544 in Active Magnetic Bearing Control System },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_125.pdf}
}
2010 Qian, K.X., Lu, M., Xu, Z. and Wang, H. A Novel PM Bearing and Its Application in Permanent Maglev Turbine Machine Proceedings of ISMB12  
Abstract: A prototype of permanent maglev turbine machine was developed. The device has a rotor and a stator, both have two PM rings with a diagonal surface (bevel plane). All rings were magnetized axially and the rotor rings have opposite magnetized direction compared with the stator rings. Their diagonal surfaces are face to face and reject each other, producing a rejection force perpendicular to the diagonal surfaces. The rotor is suspended in such way radially and axially by these two PM bearings. First experiment demonstrated that the rotor maximal eccentric distance, measured by 4 Hall sensors, would be smaller than the gap between the rotor and the stator, if the rotating speed was higher than 1800rpm, indicating that the rotor had no contact with the stator and thus was levitated stably.
BibTeX:
@inproceedings{ISMB12_126,
  author = {K. X. Qian and M.F. Lu and Z.H. Xu and H. Wang },
  title = {A Novel PM Bearing and Its Application in Permanent Maglev Turbine Machine },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_126.pdf}
}
2010 Zheng, K., Liu, H. and Yu, L. Fuzzy Modeling and Output Feedback Stabilization of a Nonlinear Magnetic Bearing with Delayed Feedback Proceedings of ISMB12  
Abstract: This paper presents a robust fuzzy logic-base control scheme for a nonlinear magnetic bearing system that is subject to time delay in feedback loop. A new Takagi-Sugeno fuzzy model is proposed to represent the nonlinear magnetic bearing. Base on the new fuzzy model, a PDC controller is designed in terms of a proposed delay-dependent stability criterion which guarantees the asymptotic stability of the fuzzy model. The results of simulation verify the effectiveness and superiority of the proposed method.
BibTeX:
@inproceedings{ISMB12_130,
  author = {Kai Zheng and Heng Liu and Lie Yu },
  title = {Fuzzy Modeling and Output Feedback Stabilization of a Nonlinear Magnetic Bearing with Delayed Feedback },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_130.pdf}
}
2010 Tian, F., Wang, X., Qian, J., Yang, Y. and Guo, L. Analysis of Structure and Mechanics Feature of Axial Permanent Bearings Based on ANSYS Proceedings of ISMB12  
Abstract: This paper analyzes a single axial permanent bearing and two kinds of symmetrical-mounted axial permanent bearings by ANSYS solving method of magnetic field. The effect of axial dimension and air gap length between two magnetic rings on axial restoring force and stiffness of bearings is calculated, which provides the foundation for further designing and guiding suggestion for application of permanent magnetic bearing constructed by magnetic rings.
BibTeX:
@inproceedings{ISMB12_132,
  author = {Feng Tian and Xiping Wang and Jing Qian and Yumin Yang and Li Guo },
  title = {Analysis of Structure and Mechanics Feature of Axial Permanent Bearings Based on ANSYS },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_132.pdf}
}
2010 Tian, Y., Sun, Y. and Yu, L. LQG Control of Hybrid Foil-Magnetic Bearing Proceedings of ISMB12  
Abstract: A hybrid foil magnetic bearing is a combination of the foil bearing and magnetic bearing, which have the advantages of both and can also share loads between them. In this paper, the model of a rigid rotor supported by two hybrid foil magnetic bearings was established, and a controller based on the Linear Quadratic Gaussian control law was designed for this new type of bearing. Finally, Simulation was performed to verify the performance of the rotor-bearing system, and the results show that the system could work well at situations with strong perturbation forces.
BibTeX:
@inproceedings{ISMB12_135,
  author = {Ye Tian and Yanhua Sun and Lie Yu },
  title = {LQG Control of Hybrid Foil-Magnetic Bearing },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_135.pdf}
}
2010 Tian, Y., Sun, Y. and Yu, L. Harmonic Analysis of Eddy Current Loss for Magnetic Thrust Bearings Proceedings of ISMB12  
Abstract: In MTBs, high eddy current loss will be produced in the solid stator and thrust disk. They play a significant role in limiting the high-speed operation of rotating actuators. In this paper, the flux path of a MTB was divided into six elementary parts according to the distributions of flux. A frequency model of eddy current losses for every iron part was proposed and the boundary condition was defined by a fractional transfer function. Results from FEM show its validity.
BibTeX:
@inproceedings{ISMB12_136,
  author = {Yongsheng Tian and Yanhua Sun and Lie Yu },
  title = {Harmonic Analysis of Eddy Current Loss for Magnetic Thrust Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_136.pdf}
}
2010 Su, W., Geng, H., Liu, H. and Yu, L. Effects and Compensations of Time Delay on the Dynamic Stiffness and Damping Coefficients of Active Magnetic Bearings Proceedings of ISMB12  
Abstract: Aiming at the problem of small time delay in the control system of an active magnetic bearing (AMB), the direct approach is applied to study the effects and compensation of time delay on the dynamic stiffness and damping coefficients of active magnetic bearings. Second-derivative feedback is used to compensate time delay effects, and performance of the controller has been verified. The results indicate that the time delay mainly affects the dynamic performance of AMB system in the upper frequency band, and results in the increasing of bearing dynamic stiffness coefficient and the decreasing of bearing dynamic damping coefficient with the high-speed AMB, respectively. The relationship between second-derivative and bearing performance is investigated, and it is shown that the time delay effects on the bearing properties may be effectively compensated by using the second-derivative feedback.
BibTeX:
@inproceedings{ISMB12_139,
  author = {Wenjun Su and Haipeng Geng and Heng Liu and Lie Yu },
  title = {Effects and Compensations of Time Delay on the Dynamic Stiffness and Damping Coefficients of Active Magnetic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_139.pdf}
}
2010 Liu, B., Fang, J. and Liu, G. Gimballing Control and Its Implementation for a Magnetically Suspended Flywheel Proceedings of ISMB12  
Abstract: The idea of utilizing the gyroscopic effects in rotor dynamics level was proposed to improve the precision of gimbaling control of a magnetically suspended flywheel(MSFW). The dynamics couplings of a rotor are the main problems of tracking control. A feed forward matrix was proposed. Implementations of gimballing control were discussed. Angular displacement stiffness will degrade the precision of gimballing control, and additional currents were added to coils to compensate the disturbance. The experimental results show that adopting the proposed methods, the tested MSFW can generate a torque of 1.92Nm.
BibTeX:
@inproceedings{ISMB12_14,
  author = {Bin Liu and Jiancheng Fang and Gang Liu },
  title = {Gimballing Control and Its Implementation for a Magnetically Suspended Flywheel },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_14.pdf}
}
2010 Tonoli, A., Amati, N., Genta, G., Impinna, F. and Detoni, J.G. A New Stabilization Technique for Electrodynamic Bearings Proceedings of ISMB12  
Abstract: Electrodynamic bearings (EDBs) are a kind of passive magnetic bearing based on the eddy currents that develop between a rotating conductor and a static magnetic field. This type of bearing is capable of providing radial stiffness compatible with high speed rotor requirements, but is intrinsically unstable. The stabilization of the rotor is the greatest challenge to the application of electrodynamic bearings. The present work presents a new stabilization strategy for EDBs. The proposed solution is studied by means of analytic models. Experimental results are shown to prove the validity of the modeling and of the stabilization solution.
BibTeX:
@inproceedings{ISMB12_142,
  author = {Andrea Tonoli and Nicola Amati and Giancarlo Genta and Fabrizio Impinna and Joaquim Girardello Detoni},
  title = {A New Stabilization Technique for Electrodynamic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_142.pdf}
}
2010 Tonoli, A., Amati, N., Impinna, F., Detoni, J.G., Bleuler, H. and Sandtner, J. Dynamic Modeling and Experimental Validation of Axial Electrodynamic Bearings Proceedings of ISMB12  
Abstract: Eddy current effects are the base of electrodynamic bearings principle. They arise when a conductor moves in a magnetic field. As they are passive by nature, no additional instrumentation such as sensor or power electronics are needed, and this implies several advantages such as the reduced complexity, improved reliability and smaller size and cost. Electrodynamic bearings have also drawbacks such as the difficulty in ensuring a stable levitation in a wide speed range, therefore the bearing design must be based on a dynamic analysis to investigate the stability issue. A prediction of the dynamic performance of rotating systems equipped with axial/radial electrodynamic bearings needs a model able to describe the dynamic behavior. The present paper is devoted to describe and validate experimentally the quasi static and the dynamic model of axial electrodynamic bearings.
BibTeX:
@inproceedings{ISMB12_143,
  author = {Andrea Tonoli and Nicola Amati and Fabrizio Impinna and Joaquim Girardello Detoni and Hannes Bleuler and Jan Sandtner},
  title = {Dynamic Modeling and Experimental Validation of Axial Electrodynamic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_143.pdf}
}
2010 Tonoli, A., Bonfitto, A., Genta, G., Silvagni, M. and Bleuler, H. Self-Sensing Active Magnetic Dampers for Vibration Control Proceedings of ISMB12  
Abstract: The aim of this paper is to investigate the potential of a self-sensing strategy in the case of an electromagnetic damper for the vibration control of flexible structures and rotors. The study has been performed in the case of a single degree of freedom mechanical oscillator actuated by a couple of electromagnets. The self-sensing system is based on a Luenberger observer. Two sets of parameters have been used: nominal ones (based on simplifications on the actuator model) and identified ones. In the latter case, the parameters of the electromechanical model used in the observer are identified starting from the open-loop system response. The observed states are used to close a state-feedback loop with the objective of increasing the damping of the system. The results show that the damping performance are good in both cases, although much better in the second one. Furthermore, the good correlation between the closed loop model response and the experimental results validates the modelling, the identification procedure, the control design and its implementation. The paper concludes on a sensitivity analysis, in which the influence of the model parameters on the closed-loop response is shown.
BibTeX:
@inproceedings{ISMB12_144,
  author = {Andrea Tonoli and Angelo Bonfitto and Giancarlo Genta and Mario Silvagni and Hannes Bleuler},
  title = {Self-Sensing Active Magnetic Dampers for Vibration Control },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_144.pdf}
}
2010 Bleuler, H., Bonfitto, A., Tonoli, A. and Amati, N. Miniaturized Gyroscope with Bearingless Configuration Proceedings of ISMB12  
Abstract: One of the current topics in magnetic bearings technology is the exploration of their potential in the field of micro machines. Up to now in literature there are very few examples of realization and most of them are just experimental systems but it seems that further investigations can be performed. In this paper the evaluation of the performance of micro magnetic bearings in an application dealing with the navigation of planes and cars is reported. The realization of a miniaturized gyroscopic sensor based on active magnetic bearings (AMBs) is described from the mechanical to the control design. The mechanical and the actuation systems are analyzed along with the realization of the model and of two different control design strategies: a H(inf) and a decentralized MultiSISO control (a classical Proportional Derivative (PD) on each axis). For both the proposed approaches the modelling and the control design phases are discussed. The H(inf) strategy has been evaluated to perform a robust control and consists in a Plant Non-Inverting GS/T Weighting scheme with an explicit integral action and an anti wind-up action. In the case of decentralized strategy, the model of the system containing the transformation from the center mass coordinates to the actuators coordinates is exposed along with the tuning of the proportional and derivative actions. The numerical and experimental results obtained on the prototype with the two control strategies are compared to evaluate their behaviour in this application. Finally, the principle used to make the rotor spinning is exposed and the rotation results are discussed.
BibTeX:
@inproceedings{ISMB12_145,
  author = {Hannes Bleuler and Angelo Bonfitto and Andrea Tonoli and Nicola Amati},
  title = {Miniaturized Gyroscope with Bearingless Configuration },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_145.pdf}
}
2010 Wu, G., Zhang, X., Zhou, J. and Wang, X. Investigation of Magnetic Field and Force on a Maglev Supporting Structure of Vertical Axis Wind Turbine Proceedings of ISMB12  
Abstract: Vertical Axis Wind Turbine (VAWT) is a type of important electric equipment. A hybrid maglev supporting structure in shaft system of VAWT is mentioned in this paper. The simulation has been conducted to study the magnetic field and force on this structure. The working condition is classified by four different length and magnetic isolated condition, three kinds of exciting currents compound modes is studied at the same time. Through the contrastive analysis of ANSYS simulation, the computed results reveal that the magnetism of pole terminals need to be isolated and face-to-face or back-to-back excitation is appropriate for magnet units in differential mode. The magnetic field and magnetic force are also emulated when the rotor working the position of equilibrium.
BibTeX:
@inproceedings{ISMB12_146,
  author = {Guoqing Wu and Xudong Zhang and Jingling Zhou and Xiping Wang },
  title = {Investigation of Magnetic Field and Force on a Maglev Supporting Structure of Vertical Axis Wind Turbine },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_146.pdf}
}
2010 Deckert, A., Keller, U. and Fasoulas, S. MagBeS-Magnetic Bearing Simulator for Analyzing and Designing Magnetically Levitated Rotors Proceedings of ISMB12  
Abstract: MagBeS is aMatlab based Graphical User Interface that can be used to analyze or design magnetically levitated rotors using a parametric multiphysical algorithm. The paper includes a description of the computation algorithm and shows simulation results for analyzing magnetic bearings using MagBeS, with a focus on the capability of this tool.
BibTeX:
@inproceedings{ISMB12_15,
  author = {Antje Deckert and Uwe Keller and Stefanos Fasoulas},
  title = {MagBeS-Magnetic Bearing Simulator for Analyzing and Designing Magnetically Levitated Rotors },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_15.pdf}
}
2010 Ma, Y., Yu, X., Yu, S., Zhang, Z. and Shi, L. Technical Design of Active Magnetic Bearings for the Helium Turbomachine of HTR-10GT Proceedings of ISMB12  
Abstract: The high temperature gas-cooled reactor (HTGR) coupled with gas turbine cycle is considered as one of the leading candidates for future nuclear power plants. The gas turbine cycle will also play an important role in the six GIV nuclear reactor systems as energy conversion system. The 10MW high temperature gas-cooled test reactor coupled with gas-turbine circle (HTR-10GT) has been carried out by the Institute of Nuclear and New Energy Technology (INET) of Tsinghua University in China since year 2002. In the power convention unit (PCU) of the HTR-10GT, the contact-free and no-lubricating active magnetic bearings (AMB) are adopted to support the vertical high-speed helium turbomachine shaft, because of their numerous advantages over the conventional oil mechanical bearings under the special reactor operating conditions. Based on the previous studie, the final engineering design of helium turbomachine and the AMBs for the HTR-10GT have been finished recently. This paper firstly introduces the design principle and technical futures of the AMBs. Then the main structure, as well as the key dimensions and parameters of the different helium turbomachine and AMB components are illustrated in detail. Further more, the load capacity of AMB and the rotor dynamics of helium turbomachine draft are analysized.
BibTeX:
@inproceedings{ISMB12_151,
  author = {Yunxiang Ma and Xiaoli Yu and Suyuan Yu and Zhijian Zhang and Lei Shi },
  title = {Technical Design of Active Magnetic Bearings for the Helium Turbomachine of HTR-10GT },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_151.pdf}
}
2010 Li, D., Yu, X., Yu, S., Zhang, Z. and Shi, L. Principle Test of Active Magnetic Bearings for the Helium Turbomachine of HTR-10GT Proceedings of ISMB12  
Abstract: The 10MW high temperature gas-cooled test reactor coupled with gas-turbine circle (HTR-10GT) is considered as one of the most important development fields of the future HTR technology due to its simple system, high efficiency and potential economical competitiveness. In the power convention unit (PCU) of the HTR-10GT, the active magnetic bearings (AMB) are adopted to support the vertical high-speed helium turbomachine shaft, its performance affect the layout of gas turbine system related with safety and economics of the nuclear power plant. In order to make a principle test for the design of AMBs of HTR-10GT, a small-scale analogue test rig has been designed and built to simulate the helium turbomachine rotor in compliance with the dynamic similarity principles. Through the test, the advanced control algorithms are validated, design and operation experiences for the next full scale experiment in the near future are accumulated.
BibTeX:
@inproceedings{ISMB12_152,
  author = {Dong Li and Xiaoli Yu and Suyuan Yu and Zhijian Zhang and Lei Shi },
  title = {Principle Test of Active Magnetic Bearings for the Helium Turbomachine of HTR-10GT },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_152.pdf}
}
2010 Chen, X. and Liu, K. A BP Neural Network Controller for Magnetic Suspended Flywheel System Proceedings of ISMB12  
Abstract: A BP neural network controller is proposed for direct suspending control for Magnetic Suspended Flywheel System (MSFS) that is supported by Active Magnetic Bearings (AMB). A one hidden layer configuration is adopted in the BP neural network, and the back propagated algorithm for network weights updating is derived based on AMB’s linear model. The discussed controller is implemented in the MSFS with random initial network weights, and it is trained online as the whole system operated. Simulations show the proposed BP neural network controller is apt to succeed in suspending the flywheel, and better performances such as precise position control, disturbance rejection, vibration suppression and quiet control are achieved under power consumption limitation. The results validate the feasibility and effectiveness of the presented BP neural network controller.
BibTeX:
@inproceedings{ISMB12_18,
  author = {Xiaofei Chen and Kun Liu },
  title = {A BP Neural Network Controller for Magnetic Suspended Flywheel System },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_18.pdf}
}
2010 Zhang, L., Liu, K. and Chen, X. FPGA-Based Implementation for Unbalance Compensation in Active Magnetic Bearings Proceedings of ISMB12  
Abstract: An FPGA implementation for unbalance compensation in AMB is proposed. The compensation method uses a generalized notch filter based on coordinate transformations. In the FPGA implementation, the lookup table is used to get the sine and cosine value, and an incremental algorithm is adopted when calculating sin ?t . The rotation speed of the flywheel rotor is considered as a constant in every iterative step. Detailed skills in HDL coding are presented. Experimental results prove that the compensation is effective over a wide range of operation speeds.
BibTeX:
@inproceedings{ISMB12_19,
  author = {Li Zhang and Kun Liu and Xiaofei Chen },
  title = {FPGA-Based Implementation for Unbalance Compensation in Active Magnetic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_19.pdf}
}
2010 Gruber, W., Huber, M., Jungmayr, G. and Amrhein, W. Passive Tilt Bearings with Zero Translational Stiffness Composed of Two Permanent Magnet Rings Proceedings of ISMB12  
Abstract: This paper presents the current state of art in the control systems applied to levitation control and typical structure of digital control system. A new approach based on programmable analogue devices is proposed and an architecture of the levitation controller is presented. Some advantages and disadvantages of the considered technology are given. Finally the possible application of typical control laws and signal processing are discussed. In the experimenThis paper deals with the computation of the axial, radial and tilt stiffness of two concentric permanent magnetic rings with axial polarization. Such compositions normally correspond to either radial or axial passive magnetic bearings. In contrast to the translational degrees of freedom this paper focuses on therotational and therefore passive tilting stiffness of such systems. An important result is the exact relative position of the concentric rings for which the radial and axial stiffness is zero and the tilt stiffness is positive. Thus, such a configuration represents a pure passive magnetic tilt bearing.
BibTeX:
@inproceedings{ISMB12_20,
  author = {Wolfgang Gruber and Manfred Huber and Gerald Jungmayr and Wolfgang Amrhein},
  title = {Passive Tilt Bearings with Zero Translational Stiffness Composed of Two Permanent Magnet Rings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_20.pdf}
}
2010 Wang, X. and Ding, Q. Current Compensation Controller with Disturbance Acceleration Observer in Bearingless Motor Proceedings of ISMB12  
Abstract: In order to improve the suspension performance of bearingless motors, the disturbances could be not neglected and some measures should be considered in the design of the controllers. In this paper, a disturbance acceleration observer is adopts based on the suspension model of the consequent-pole permanent magnet bearingless motor. And a suspension current compensation controller is proposed with the observer. In this case, an equivalent disturbance-current is utilized to compensate for the suspension current component caused by the disturbance displacement. Simulations are carried out with several kinds of displacement disturbance sources. The results demonstrate the validity of the proposed controller.
BibTeX:
@inproceedings{ISMB12_22,
  author = {Xiaolin Wang and Qiang Ding },
  title = {Current Compensation Controller with Disturbance Acceleration Observer in Bearingless Motor },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_22.pdf}
}
2010 Arredondo, I. and Jugo, J. AMB Vibration Rejection Study: Adaptive Algorithms, Notch filter and Notch Exciter Proceedings of ISMB12  
Abstract: The vibration rejection is one of the main characteristics to study in the AMB based machine’s field, mainly due to the possibility of active control. In this paper four options are studied, on one hand, the well-known solutions utilizing adaptive algorithms and Notch filter, and on the other, the combination of these both (leaving the vibration in open loop) and a new method with a Notch Exciter. As the result of the comparison between them it is concluded that the election of one of the methods depends on the used specific system. Even though, the new proposed solution based on the Notch Exciter seems to be a good alternative for a lot of purposes due to its easy implementation, high working frequency range, low computational cost and high robustness.
BibTeX:
@inproceedings{ISMB12_23,
  author = {Inigo Arredondo and Josu Jugo},
  title = {AMB Vibration Rejection Study: Adaptive Algorithms, Notch filter and Notch Exciter },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_23.pdf}
}
2010 Ueno, S., Okamura, T., Sakagami, M. and Tanaka, S. Development of Miniaturized Regenerative Pump using Axial Self-bearing Motor Proceedings of ISMB12  
Abstract: This paper describes the structure and performance of miniaturized regenerative pumps with an axial self-bearing motor. Two types of pump are introduced: a single-type pump, which has one flow channel on one side of the rotor driven by a single-type axial gap self-bearing motor, and a push-pull-type pump, which has two flow channels on both sides of the rotor driven by a push-pull-type axial gap self-bearing motor. Pump performance and efficiency are evaluated, and the feasibility of the proposed pumps is discussed.
BibTeX:
@inproceedings{ISMB12_24,
  author = {Satoshi Ueno and Toshiyuki Okamura and Masaaki Sakagami and Shigeo Tanaka},
  title = {Development of Miniaturized Regenerative Pump using Axial Self-bearing Motor },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_24.pdf}
}
2010 Zhong, J. and Li, L. Switch-Driving Eddy-Current Displacement Sensing Based on Power Loss Proceedings of ISMB12  
Abstract: The principle of a switch-driving eddy-current displacement sensor is analyzed based on the eddy current power loss. This sensor converts the power loss into a working current by using switching circuits, in which a DC current related to the gap is picked out with a low pass filter. The displacement of the target thus could be obtained. A series of static experiments are carried out with iron, aluminum and nonmagnetic stainless steel as the targets, finally giving promising results.
BibTeX:
@inproceedings{ISMB12_26,
  author = {Jianpeng Zhong and Lichuan Li },
  title = {Switch-Driving Eddy-Current Displacement Sensing Based on Power Loss },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_26.pdf}
}
2010 Smirnov, A., Jastrzebski, R.P. and Hynunen, K.M. Gain-Scheduled and Linear Parameter-Varying Approaches in Control of Active Magnetic Bearings Proceedings of ISMB12  
Abstract: In this paper Linear Parameter Varying, gain-scheduled and robust approaches for a controller synthesis are considered in an application for a highly gyroscopic system. A transient during a rotor start up and a steady state disturbance attenuation are evaluated. Based on these measurements a comparison of different control approaches is done.
BibTeX:
@inproceedings{ISMB12_27,
  author = {Alexander Smirnov and Rafal P. Jastrzebski and Katja M. Hynunen},
  title = {Gain-Scheduled and Linear Parameter-Varying Approaches in Control of Active Magnetic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_27.pdf}
}
2010 van Rensburg, J.J., van Schoor, G. and Vuuren, P.A.V. Delevitation Modelling of an Active Magnetic Bearing Supported Rotor Proceedings of ISMB12  
Abstract: For active magnetic bearings (AMBs) to be used with confidence in industrial applications, the safe failure of the AMB system should be guaranteed. The exact behaviour of the rotor on the backup bearings (BBs) is relatively uncertain [1,2,3]. Uncertainty in a failure situation means that the safe failure of the AMB system cannot be guaranteed. The purpose of the presented rotor delevitation simulation model (RDSim model) is to eliminate some of the uncertainties associated with a rotor delevitation event. The simulation model includes a flexible rotor model [4], a non-linear AMB model [5], a non-linear BB model, stator effects, active rotor braking, rotor free running, inner race speed up, AMB/BB load sharing and sudden unbalance (blade-loss simulation). The RDSim model can be used to simulate any AMB failure on one or more locations. The failure modes include power amplifier (PA) malfunction, AMB coil short-circuit, total power failure and controller failure. This paper will discuss the BBSim model; a brief explanation of each of the sub-models of the BBSim model is also given.
BibTeX:
@inproceedings{ISMB12_28,
  author = {Jan Janse van Rensburg and George van Schoor and Pieter A. Van Vuuren},
  title = {Delevitation Modelling of an Active Magnetic Bearing Supported Rotor},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_28.pdf}
}
2010 Zhao, J., Kasarda, M.E., Spangler, D., Prins, R. and Inman, D.J. Active Magnetic Bearing System Identification Using Current-Position Perturbation Proceedings of ISMB12  
Abstract: Active magnetic bearings (AMBs) are currently in operation in many commercial applications including industrial turbo machines [1] as well as turbo molecular pumps. Since AMBs have important advantages over conventional bearings, new applications of this technology are developed yearly in fields such as commercial heating and air conditioning and space based rotary equipment. A notable advantage of AMBs is the ability to act concurrently as a means of bearing support and as a shaft force sensor. Sensing the force (or reaction) that is applied to the AMB stator through the shaft rotor is achieved by measuring information about the AMB’s magnetic field. This capability has the potential to facilitate advanced health monitoring techniques as well as facilitate improvements in the continuous control of processes used in the production of microfibers and in detailed metal processing [1]. Quality control for such applications can be directly linked to real-time rotor force evaluation. Some researchers have examined the force sensing capability of magnetic bearings by using Hall effect sensors in air gaps between bearing stator and rotor components. In this approach, measured magnetic flux densities are used in force equations to determine applied bearing reactions. Other researchers have employed methods based on measuring magnetic flux density in the bearing electromagnets from electric current data to determine applied bearing reactions, thus eliminating the need for additional sensor hardware. Limitations with both methods include assumptions in the force model associated with leakage, fringing, heterogeneity of magnetic material, and non-uniformity of axial and radial air gaps due to manufacturing tolerances. Misalignment and thermal issues encountered in the field also affect model accuracies [2]. Most magnetic force models assume that these effects are negligible and/or non-measureable. The research presented in this paper introduces a new in situ approach for bearing system identification in an effort to improve magnetic force models and is based on measurement of current and position perturbations. The paper also includes initial proof-of-concept static verification of the proposed method.
BibTeX:
@inproceedings{ISMB12_29,
  author = {Jianhui Zhao and Mary E.F. Kasarda and Dewey Spangler and Robert Prins and Daniel J. Inman},
  title = {Active Magnetic Bearing System Identification Using Current-Position Perturbation},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_29.pdf}
}
2010 Garcia, J.D.G., del Nero Gomes, A.C. and Stephan, R.M. Benchmarking Control Techniques Applied to Magnetic Bearings: Performance Assessment Criteria Analysis Proceedings of ISMB12  
Abstract: Active Magnetic Bearings, due to a plant-intrinsic instability, require a control system for normal operation. Many control strategies have been proposed for the stabilization task, in some instances emphasizing market recognized control approaches, as PID controllers arranged in decentralized structures, and in other instances modern control approaches are envisaged, like LQR or H8 structures. The objective of this paper is to present criteria to assess the performance of such proposed controllers, in order to establish a metric to compare different control schemes. The performance assessment criteria discussed include time domain as well as frequency domain approaches. Such criteria are applied to two control systems used in a laboratory prototype to stabilize a bearingless motor, being one based on PID controllers and the other being a LQR scheme. Discussion of the results is used to select a metric to be applied in the comparison of some controller algorithms, both centralized and decoupled, in order to determine which control law best suits such a bearingless motor.
BibTeX:
@inproceedings{ISMB12_30,
  author = {José Dalvio Ghirello Garcia and Afonso Celso del Nero Gomes and Richard Magdalena Stephan},
  title = {Benchmarking Control Techniques Applied to Magnetic Bearings: Performance Assessment Criteria Analysis },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_30.pdf}
}
2010 Zhu, H. and Tan, E. Direct Suspension Force Control of Bearingless Permanent Magnet Synchronous Motor Proceedings of ISMB12  
Abstract: The bearingless permanent magnet synchronous motor (BPMSM) is a strong-coupled nonlinear system. To solve the difficult problem of dynamic decoupling control among torque and suspension forces, the relationship between rotor radial suspension force and flux linkage are analyzed, the theory and method of direct torque control (DTC) are applied to the suspension control of the BPMSM in the paper. A double closed-loop control system, in which the inner closed-loop is radial suspension force loop and the outer closed-loop is rotor radial displacement loop, is constructed to control the radial suspension forces directly. The direct suspension force control (DSFC) algorithm based on space vector pulse width modulation (SVM) strategy is deduced, and the DSFC system for the BPMSM are designed and simulated using Matlab software. The simulation results show that the rotor can be suspended stability, torque and radial suspension forces can be controlled independently, the structure of control system is simple, and control system has strong robustness.
BibTeX:
@inproceedings{ISMB12_32,
  author = {Huangqiu Zhu and Er Tan },
  title = {Direct Suspension Force Control of Bearingless Permanent Magnet Synchronous Motor },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_32.pdf}
}
2010 Zhang, W., Zhu, H. and Yang, Z. Principle and Control of Radial AC Hybrid Magnetic Bearing Proceedings of ISMB12  
Abstract: In the paper, the configuration and principle of the radial AC hybrid magnetic bearings are expounded, and the mathematical models of suspension forces are deduced by using the method of equivalent magnetic circuits. Nonlinearities of suspension forces and cross coupling between the two degrees of freedom are studied further by calculating the suspension forces at different displacements and control currents to validate the feasibility of the mathematical models. Then based on the mathematics models , the digital control system is designed. The hardware based on TMS320F2812 is developed, and the software of control system is developed. The experiments are completed and the test results have shown that the AC hybrid magnetic bearing has good dynamic and static performance.
BibTeX:
@inproceedings{ISMB12_33,
  author = {Weiyu Zhang and Huangqiu Zhu and Zebin Yang },
  title = {Principle and Control of Radial AC Hybrid Magnetic Bearing },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_33.pdf}
}
2010 Zhang, Q., Deng, Z. and Yang, Y. Influence of Main Winding Connection on Vibration and Acoustic Noise of Bearingless Switched Reluctance Motors Proceedings of ISMB12  
Abstract: Fundamental principle and control strategy of main winding square-wave current of bearingless switched reluctance motors are introduced. Since rotor eccentric exists when operation of BSRM, influence of eccentric on air-gap flux distribution with different main winding connections is analyzed. As pulsation of radial force is origin of vibration and noise of SRM, a radial force mathematic model is introduced considering magnetic saturation. Winding currents are different with different main winding connections even under the same load, thus radial forces of stator poles are different. Influence of main winding connections on vibration of stator is researched and the conclusion of all parallel of main winding coils is in favor of vibration reduction is draw.
BibTeX:
@inproceedings{ISMB12_34,
  author = {Qianying Zhang and Zhiquan Deng and Yan Yang },
  title = {Influence of Main Winding Connection on Vibration and Acoustic Noise of Bearingless Switched Reluctance Motors },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_34.pdf}
}
2010 Herzog, R. and Blanc, P. A Comparison of Linear Periodic and Nonlinear Control Strategies for Self-Sensing Magnetic Bearings Proceedings of ISMB12  
Abstract: In this paper, the controller design for self–sensing magnetic bearings is considered using a linear time periodic (LTP) framework. The time periodicity comes from a deliberate bias flux excitation signal allowing to improve the plant properties. Design trade–offs using periodic controllers are investigated. Three design objectives are considered: 1) low sensitivity norm to ensure good robustness, 2) low controller gain to attenuate current measurement noise and to avoid voltage saturation, and 3) low mechanical compliance against external perturbation forces to ensure high bearing stiffness. Different LTP H8 controllers are designed using lifting techniques and linear matrix inequalities (LMI). The resulting controllers are validated using closed–loop simulations with the nonlinear plant.
BibTeX:
@inproceedings{ISMB12_35,
  author = {Raoul Herzog and Philippe Blanc},
  title = {A Comparison of Linear Periodic and Nonlinear Control Strategies for Self-Sensing Magnetic Bearings},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_35.pdf}
}
2010 Kunxi, Q., Zihao, X. and Hao, W. Relation between Minimal Speed and Rotational Inertia of Stable PM Maglev Bearing Rotator Proceedings of ISMB12  
Abstract: The authors’ former works demonstrated that a passive magnetic (PM) rotator supported merely by PM bearings has a minimal speed, above which it can stabilize its equilibrium, under the function of a so-called Gyro-effect. It is unclear, however, by which factors is this minimal speed determined. To investigate the effect of rotor inertia on minimal speed, three same rotors made of different materials were manufactured: rotor A was made of plastic and its rotary inertia is 6.293×10-5 (kg·m2); rotor B was made of aluminum and its inertia is 1.074×10-4 (kg·m2); rotor C was made of steel and its inertia is 2.081×10-4 (kg·m2).The rotors were tested in a model with PM bearings and the maximal eccentric distance of the rotors was measured. In case the maximal eccentric distance of the rotor was smaller than the gap between the rotor and the stator, the rotor could be considered being suspended. In such way the minimal speed for stable levitation of the rotor A, B and C was obtained to be 4597, 3030 and 2222 rpm respectively. It concluded that the minimal speed increases with the square of decreasing inertia according to a formula: [y=1/(a+bx+cx2), here y: minimal speed, with unit rad/s; x: rotational inertia, with unit kg·m2; a, b, c are constants: a=3.5367×10-5,b= 39.1012,c=-8.8726×104].
BibTeX:
@inproceedings{ISMB12_36,
  author = {Qian Kunxi and Xu Zihao and Wang Hao},
  title = {Relation between Minimal Speed and Rotational Inertia of Stable PM Maglev Bearing Rotator },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_36.pdf}
}
2010 Wang, B., Deng, Z., Wang, S., Li, X., Zhao, X. and Lian, G. Analysis of Cross Feedback Control for the Magnetically Suspended Flywheel Rotor Proceedings of ISMB12  
Abstract: For the magnetically suspended flywheel rotor of big moment of inertia, gyro effect is significant when it is rotating at high speed. Traditional decentralized PD control cannot insure the stability of the system. This paper mainly studies the cross feedback control, analyzes the velocity and displacement cross feedback, explains the control principle of cross feedback. The poles of precession and nutation, and the damping curves are given, showing the trends. And the results of the simulation experiments show that the cross feedback control is effective to restrain the gyro effect. Flywheel systems are widely used in the energy storage, uninterruptible power supply, satellite attitude control, adopting magnetically suspending is an important developing way for the flywheel systems. Magnetic bearing is a new kind of electromagnetic bearing using magnetic force to balance the rotor between the stator. Magnetically suspended machines have the unique advantages of contact-free, without lubrication, adjustable stiffness and damping that traditional bearing cannot substitute. Magnetically suspended flywheel systems are stable in theory adopting decentralized PD control. However, for the flywheel rotor of big moment of inertia, gyro effect is significant when rotating at high speed, constrains to raise the rotating speed, the stability is deteriorated, new control strategy is needed to restrain the gyro effect. This paper mainly studies the cross feedback control aimed at the gyro effect. The control principle of velocity and displacement cross feedback are introduced, analyzed the poles, frequencies and damping of precession and nutation, and the results of simulation experiments are given.
BibTeX:
@inproceedings{ISMB12_38,
  author = {Bo Wang and Zhiquan Deng and Shishan Wang and Xiangsheng Li and Xusheng Zhao and Guangkun Lian },
  title = {Analysis of Cross Feedback Control for the Magnetically Suspended Flywheel Rotor },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_38.pdf}
}
2010 Xiaolin, W., Wang, S., Zhiquan, D. and Shengzou, Y. Analysis of Fault-tolerance Control Strategy of the Single Winding Bearingless PM Slice Motor Proceedings of ISMB12  
Abstract: There always exists a problem towards multi-phase concentrated winding bearingless slice motor that the fault of the windings would lead to the motors’ abnormal running when the control strategy is not changed. Taking the six-phases single winding bearingless slice motor for example. Firstly, the short-circuit current of the fault winding was analyzed while each of the winding worked at short-circuit fault state and the expression of the short-circuit current was derived based on the voltage balance equation of the fault winding. Secondly, every possible fault state in this motor was analyzed, and the corresponding fault-tolerance control strategy was presented based on the stator-current reconfiguration principle. In the strategy, the stator-current mathematical model was derived based on the mathematical model of motor’s levitation force and torque. Finally, the fault-tolerance control strategy was verified by comparing levitation force’s pulse and torque’s pulse in the simulation.
BibTeX:
@inproceedings{ISMB12_42,
  author = {Wang Xiaolin and Sheng Wang and Deng Zhiquan and Yue Shengzou},
  title = {Analysis of Fault-tolerance Control Strategy of the Single Winding Bearingless PM Slice Motor },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_42.pdf}
}
2010 Guo, L., Wan, L. and Yu, S. Theoretical Investigation on Dynamic Behavior of AMB-Rotor System subject to Base Motion Disturbances Proceedings of ISMB12  
Abstract: A theoretical investigation on the dynamic behavior of an AMB-rotor system subject to base motion disturbances was carried out in the present paper. The rotor responses of the AMB-rotor system under the rigid and flexible base supporting conditions were compared, which will provide theoretical basis on the base disturbance rejection performance research of AMB-rotor systems. The results show that under the rigid base supporting condition, the capacity of the AMB’s controller to suppress the base disturbances is very limited. In order to attenuate the disturbance responses, a flexible base with specified mass and stiffness should be adopted in the AMB-rotor system.
BibTeX:
@inproceedings{ISMB12_43,
  author = {Leilei Guo and Li Wan and Suyuan Yu },
  title = {Theoretical Investigation on Dynamic Behavior of AMB-Rotor System subject to Base Motion Disturbances },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_43.pdf}
}
2010 Zhang, S., Xie, Z. and Shi, Q. Research on H(inf) Control for Flexible Rotor System Supported by Active Magnetic Bearings and Metal Rubber Rings Proceedings of ISMB12  
Abstract: To lighten burden for Active Magnetic Bearing (AMB), Metal Rubber Ring (MRR) is introduced into the AMB system. Based on mixed-sensitivity H? control theory, the H? controller is designed and realized based on TMS320F2812DSP for the system. The influence of Weight Functions on dynamic characteristics of the system is investigated in this paper. The theoretical analysis and experimental results show that H? control can help the system operate over the first two bending critical speeds safely and stably.
BibTeX:
@inproceedings{ISMB12_47,
  author = {Shuying Zhang and Zhenyu Xie and Qingcai Shi },
  title = {Research on H(inf) Control for Flexible Rotor System Supported by Active Magnetic Bearings and Metal Rubber Rings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_47.pdf}
}
2010 Maruo, E. and Komori, M. Basic Study on Superconducting Magnetic Bearing using Superconducting Bulk and Coil Proceedings of ISMB12  
Abstract: Our group has developed a superconducting magnetic levitation (SML) with superconducting coil for magnetically levitated conveyers used for clean environments. In this paper, dynamic characteristics of the SML with superconducting coil are discussed. The damping for the SML with superconducting coil is compared with the SML without superconducting coil. The damping for the SML with PD control is also discussed.
BibTeX:
@inproceedings{ISMB12_48,
  author = {Eijiro Maruo and Mochimitsu Komori},
  title = {Basic Study on Superconducting Magnetic Bearing using Superconducting Bulk and Coil },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_48.pdf}
}
2010 Wang, H., Liu, K. and Xiao, K. Design, Analysis and Simulation of a Triaxial Spacecraft Attitude Control Testbed Based on Magnetic Bearing Proceedings of ISMB12  
Abstract: Because of its technological significance, spacecraft attitude control testbed, have been widely used for the Earth-based testing of the spacecraft attitude systems. Traditionally, the spacecraft attitude control testbed is based on spherical air bearing, in this paper, a new kind of triaxial attitude control testbed (TACT) based on magnetic bearing is designed. The structure of the TACT is introduced, including it working principle. This paper especially described the hemispherical magnetic bearing applied in the TACT, designed a new kind of hemispherical magnetic bearing, and analyzed the distribution of the magnetic field in the bearing. In this paper, the magnetic force of the magnetic bearing is obtained by electromechanical-energy-conversion principles, the analytical equation of the mathematical model of the TACT is deduced, which make the feasibility of this design is verified.
BibTeX:
@inproceedings{ISMB12_50,
  author = {Haoze Wang and Kun Liu and Kai Xiao },
  title = {Design, Analysis and Simulation of a Triaxial Spacecraft Attitude Control Testbed Based on Magnetic Bearing },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_50.pdf}
}
2010 Jastrzebski, R.P., Tolsa, K. and Iskanius, M. Customization of Digital Circuit for Material-Independent Eddy Current Proximity Sensor for Active Magnetic Bearings Proceedings of ISMB12  
Abstract: The state of the art, commercial eddy current sensors can provide excellent quality of the measured position; however, the easier system integration, size of the conditioning electronics, cost, and interfacing delays are unfavorable. In this paper, a customization of the basic conventional single-coil eddy current proximity sensor for active magnetic bearings is presented. The signal conditioning is designed to be integrated with the main signal processing unit, which can also incorporate the active magnetic bearing system controller. The nonlinearities and dependencies on the electromagnetic properties of the target material are eliminated using software implementation. The highest signal to noise ration is observed for the aluminium-alloy target. It is shown that for the studied sensor the measuring range and accuracy are limited when under the materialindependent operation.
BibTeX:
@inproceedings{ISMB12_51,
  author = {Rafal P. Jastrzebski and Kimmo Tolsa and Matti Iskanius},
  title = {Customization of Digital Circuit for Material-Independent Eddy Current Proximity Sensor for Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_51.pdf}
}
2010 Zhang, K. and Zhang, X. Experimental Research on Unbalance Control of Active Magnetic Bearings Proceedings of ISMB12  
Abstract: Two unbalance control methods, General Notch Filter (GNF) and LMS (least mean square), for active magnetic bearings (AMBs) were applied to a high speed rotor supported by AMBs. The rotor operation was greatly influenced by a large residual unbalance in the rotor and some low frequency vibration modes from the structure of the rotor system. GNF was used to help the rotor to increase its dynamic balance efficiency with two different methods. To achieve a better unbalance cancellation effect for the rotor in a large rotation speed range, GNF and LMS methods were combined in a single unbalance controller and performed in different speed ranges. A simple but effective method was used to achieve a smooth switching of the two methods. Corresponding experiment results are provided. GNF algorithm increased the balance efficiency. The smooth switching of GNF and LMS was successful and the unbalance control effects were improved.
BibTeX:
@inproceedings{ISMB12_52,
  author = {Kai Zhang and Xiaozhang Zhang },
  title = {Experimental Research on Unbalance Control of Active Magnetic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_52.pdf}
}
2010 Lei, Z. and Hawkins, L. A Model Based Digital PI Current Loop Control Design for AMB Actuator Coils Proceedings of ISMB12  
Abstract: This paper presents a digital PI current loop control design method for AMB actuator coils. The design takes into consideration the dynamics of each function block in the current loop. For the control of radial bearing actuator current, the digital redesign approach is used: an analog PI controller is designed first with root locus method and then discretized to obtain its digital counterpart. For the control of thrust bearing actuator current, eddy current effects are also considered as they cause frequency dependant inductance and resistance of the thrust coil. A swept sine test is conducted to measure the impedance of the thrust coil. Then a Matlab/Simulink model is built to carry out a frequency domain design of the digital PI controller with the measured impedance.
BibTeX:
@inproceedings{ISMB12_53,
  author = {Zhu Lei and Larry Hawkins},
  title = {A Model Based Digital PI Current Loop Control Design for AMB Actuator Coils },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_53.pdf}
}
2010 Subkhan, M. and Komori, M. Improvement of Compact Energy Storage Flywheel System Using SMB and PMB Proceedings of ISMB12  
Abstract: Since few years ago, electrical energy storage had been attracted as an effective use of electricity and coping with the momentary voltage drop. Above all, energy storage flywheel systems using superconductor have advantages of long life, high energy density, and high efficiency. Our experimental machine uses a superconducting magnetic bearing (SMB) together with a permanent magnet bearing (PMB) and plans to reduce the overall cost and cooling cost. Energy storage flywheel systems operate by storing energy mechanically in a rotating flywheel. The generating motor is used to rotate flywheel and to generating electricity from flywheel rotational. The generating motor consists of 2-phase 4-poles brush-less DC motor and a Hall sensor. A purpose of this research is the development of a compact energy storage flywheel system using SMB and PMB. This paper shows the new model of flywheel by using yajirobei (balancing toy) principle that has higher storage energy comparing with conventional one, the improvement and evaluation of motor drive (DC motor) to increase the speed rotating, and estimating the system at momentary voltage drop.
BibTeX:
@inproceedings{ISMB12_54,
  author = {Mukhamad Subkhan and Mochimitsu Komori},
  title = {Improvement of Compact Energy Storage Flywheel System Using SMB and PMB },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_54.pdf}
}
2010 He, D., Shinshi, T., andTakashi Yuzawa, X.Z. and Sato, T. Cooperative Control of a Maglev Local Actuator with a Conventional EDM Machine for High Speed Electrical Discharge Machining Proceedings of ISMB12  
Abstract: During the process of electrical discharge machining (EDM), the distance between a work-piece and an electrode, which are submerged in dielectric machining fluid, changes as material is being removed from the work-piece and the electrode. In order to maintain a suitable distance to the work-piece to achieve a constant electrical discharge, a cooperative control system, consisting of a maglev local actuator and a conventional EDM machine, re-positions the electrode precisely and speedily.
BibTeX:
@inproceedings{ISMB12_55,
  author = {Dongjue He and Tadahiko Shinshi and Xiaoyou Zhang andTakashi Yuzawa and Tatsushi Sato},
  title = {Cooperative Control of a Maglev Local Actuator with a Conventional EDM Machine for High Speed Electrical Discharge Machining },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_55.pdf}
}
2010 Zhuang, Z., Deng, Z., Cao, X., Yao, T., Zhou, Q. and Fan, N. Modeling and Simulation of Bearingless Switched Reluctance Motor in Full-period Generating Mode Based on Matlab Proceedings of ISMB12  
Abstract: In this paper, the model of bearingless switched reluctance motor in full-period generating mode is established using relative blocks of MATLAB/SIMULINK. The validity of simulation model is tested and verified through the derived waveform without considering levitation force. The model is simulated to analyze the influence of chopper current and speed on output voltage. Relations between radial forces and winding currents are studied from the simulation results.
BibTeX:
@inproceedings{ISMB12_56,
  author = {Zheng Zhuang and Zhiquan Deng and Xin Cao and Tian Yao and Qin Zhou and Na Fan },
  title = {Modeling and Simulation of Bearingless Switched Reluctance Motor in Full-period Generating Mode Based on Matlab },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_56.pdf}
}
2010 Pilat, A. Testing of the Programmable AMB Spring and Damping Forces in a Flexible Rotor Test-Rig Mode Proceedings of ISMB12  
Abstract: This paper presents the 3 coils Active Magnetic Bearing (AMB) applied to the spring and damping forces generation in the flexible rotor mode. A nonlinear model is linearized for the rotor located at the bearing center. A state feedback controller is proposed and a closed loop matrix is given in the final form. Stiffness and damping factors are adjusted for experimental purposes to show effects of the programmable advantages of the AMB. The experimental results illustrate the damped rotor vibrations under an external pulse excitation generated by one of electromagnets.
BibTeX:
@inproceedings{ISMB12_57,
  author = {Adam Pilat},
  title = {Testing of the Programmable AMB Spring and Damping Forces in a Flexible Rotor Test-Rig Mode },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_57.pdf}
}
2010 Pilat, A. Features and Limitation of the Programmable Analogue Signal Processing for Levitated Devices Proceedings of ISMB12  
Abstract: This paper presents the current state of art in the control systems applied to levitation control and typical structure of digital control system. A new approach based on programmable analogue devices is proposed and an architecture of the levitation controller is presented. Some advantages and disadvantages of the considered technology are given. Finally the possible application of typical control laws and signal processing are discussed. In the experimen
BibTeX:
@inproceedings{ISMB12_58,
  author = {Adam Pilat},
  title = {Features and Limitation of the Programmable Analogue Signal Processing for Levitated Devices },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_58.pdf}
}
2010 Zhang, G., Yin, Q., Jiang, D. and Gao, G. Dynamic Analysis of the Permanent Magnetic Bearing-Rotor System Proceedings of ISMB12  
Abstract: The permanent magnetic bearings have many advantages: simple structure, free-friction, low-cost, etc. They can make up various magnetic bearing systems with mechanical bearings or electromagnetic bearings combined, thus have broad prospects. In the paper, the permanent magnet bearings - rigid rotor dynamics model is established. The stiffness matrix is built based on the equivalent electricity model and the preliminary dynamic analysis of permanent magnet bearing-rotor system is drawn. It laid a good foundation for the further researches on permanent magnetic bearing-rotor system.
BibTeX:
@inproceedings{ISMB12_59,
  author = {Gang Zhang and Qingzhen Yin and Dede Jiang and Gang Gao},
  title = {Dynamic Analysis of the Permanent Magnetic Bearing-Rotor System },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_59.pdf}
}
2010 Masala, A., Vannini, G., Lacour, M., Tassel, F.-M. and Camatti, M. Lateral Rotordynamic Analysis and Testing of a Vertical High Speed 12.5MW Motorcompressor Levitated by Active Magnetic Bearings Proceedings of ISMB12  
Abstract: A new high performance motorcompressor for subsea application, equipped with Active Magnetic Bearings (AMBs) from S2M, was developed by GE Oil&Gas. This paper presents the main steps of AMBs integration and rotordynamic assessment of Blue-C motorcompressor. A brief summary of acceptance test results and rotordynamic performances is finally illustrated.
BibTeX:
@inproceedings{ISMB12_60,
  author = {Andrea Masala and Giuseppe Vannini and Michel Lacour and Francois-Marie Tassel and Massimo Camatti},
  title = {Lateral Rotordynamic Analysis and Testing of a Vertical High Speed 12.5MW Motorcompressor Levitated by Active Magnetic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_60.pdf}
}
2010 Arkadiusz, M. and Zdzislaw, G. Energy Save Robust Control of Active Magnetic Bearings in Flywheel Proceedings of ISMB12  
Abstract: The paper reports on the investigation and developed of flywheel device as energy storage prototype. The FESS is designed to run in vacuum and is supported on low energy controlled active magnetic bearings (AMBs). The goal was to design and experimental verification of the self integrated flywheel conception with smart control of energy flow and accumulation. The low power control, with reduced bias current, approach of the flywheel active magnetic bearings is used. The weighting functions are designed in order to meet robust control conditions. The laboratory investigations of the flywheel with high gyroscopic effects operated at low speed meet the control and energy performances requirements.
BibTeX:
@inproceedings{ISMB12_61,
  author = {Mystkowski Arkadiusz and Gosiewski Zdzislaw},
  title = {Energy Save Robust Control of Active Magnetic Bearings in Flywheel },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_61.pdf}
}
2010 Wei, C. and Söffker, D. MIMO-control of a Flexible Rotor with Active Magnetic Bearing Proceedings of ISMB12  
Abstract: The paper presents a comparison of different selected MIMO (Multi Input – Multi Output)-control algorithms applied to a test rotor supported by magnetic bearings in the lateral direction. Here, the contribution is focused on the lateral direction. The rotor is considered as flexible, correspondingly, a FE-model is created, and digital controllers are employed. Moreover, a challenge of controlling the rotors of turbocompressors is to take into account the effects of the fluid forces, which destabilize the first forward mode shape in high pressure applications.
BibTeX:
@inproceedings{ISMB12_65,
  author = {Chunsheng Wei and Dirk Söffker},
  title = {MIMO-control of a Flexible Rotor with Active Magnetic Bearing},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_65.pdf}
}
2010 Wu, X., Hu, Y., Zhu, W. and Zhang, J. Research on the Principle of Suspension-Type Needle Selection and Its Modeling Proceedings of ISMB12  
Abstract: This paper has proposed a kind of suspension-type needle selecting device,designed its 3D model method and the needle alignment on the circular knitting machine. By making finite element analysis on suspension-type needles based on the driving principles, we can get the needles’ force situation and available thickness under conditions of different permanent-magnet thickness and air gaps. The dynamic response experiment model of the suspension-type needle is also given.
BibTeX:
@inproceedings{ISMB12_66,
  author = {Xiaoguang Wu and Yefa Hu and Wenbin Zhu and Jiangang Zhang },
  title = {Research on the Principle of Suspension-Type Needle Selection and Its Modeling },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_66.pdf}
}
2010 Lima, F., Rosa, F.C. and Fumagalli, M.A. Simulation of a Neurofuzzy High Speed Estimation Applied to Magnetic Bearing Systems Proceedings of ISMB12  
Abstract: The tendency to build light and high-speed rotors, to achieve a high performance of the machine, has as consequence a possible interaction between the rotor and its stator. During this interaction, the friction between the rotor and its stator, and the high energy of the former, can produce very complicated dynamical behavior. During contact the high energy of the rotor, which is dissipated by the frictional force, can severely damage both parts [1]. Estimating the rotor speed is an important task in conventional asynchronous motors. The elimination of the mechanical sensor as an encoder or a tachometer reduces the cost, improves the precision and the reliability of the whole system. Magnetic bearings systems always use a velocity sensor. In the case of failure of this sensor, rotor speed estimation could be used, in order to bring the rotor to still stand in a safety away, avoiding the situation mentioned above, therefore, the contact between the rotor and its retainer bearings. Several techniques are available in the literature for estimating the rotor speed of asynchronous motors. Recently, soft computing techniques are carried out to cover this proposal. The adaptive neuro-fuzzy inference system (ANFIS) technique has been successfully applied to estimating the speed of a conventional asynchronous motor. This work presents a simulation of a neuro-fuzzy speed estimator for a high speed asynchronous motor within a magnetic bearing system. As mentioned, the reliability of the system can be increased.
BibTeX:
@inproceedings{ISMB12_67,
  author = {Fábio Lima and Fabiano Camargo Rosa and Marco A. Fumagalli},
  title = {Simulation of a Neurofuzzy High Speed Estimation Applied to Magnetic Bearing Systems },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_67.pdf}
}
2010 Mushi, S.E., Lin, Z. and Allaire, P.E. Stability Analysis for a Flexible Rotor on Active Magnetic Bearings subject to Aerodynamic Loads Proceedings of ISMB12  
Abstract: The development of advanced control algorithms to guarantee stability and high performance of a rotor-AMB system subject to uncertainties and disturbances is an active area of research. The model based control paradigm entails consideration of the dynamics of all components that will affect the stability and performance of a system. Control design for a flexible rotor supported on active magnetic bearings provides an additional challenge since uncertainties such as the magnitudes of cross-coupled stiffness forces strongly affect the stability of the closed-loop system. Recent work has highlighted the use of sensitivity functions in determining stability margins for AMB supported turbomachinery. The output sensitivity function provides a means of quantifying the disturbance rejection and reference command tracking properties of the closed-loop system. Our work presents an analysis of the closedloop AMB sensitivity functions of the rotor-AMB system. We present simulations of the effects of varying mid-span aerodynamic cross-coupled stiffness on stability and performance of several µ-optimal controllers designed in a mixed-sensitivity framework, measurements of experimental sensitivity functions from the levitated rotor, and recommendations on the selection of weighting functions to improve the performance.
BibTeX:
@inproceedings{ISMB12_68,
  author = {Simon E. Mushi and Zongli Lin and Paul E. Allaire},
  title = {Stability Analysis for a Flexible Rotor on Active Magnetic Bearings subject to Aerodynamic Loads },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_68.pdf}
}
2010 Schaede, H., Butzek, N. and Rinderknecht, S. Model Based Fault-Detection and -Diagnosis using Active Magnetic Bearings Proceedings of ISMB12  
Abstract: This paper shows how model based fault detection and diagnosis can be integrated into the active magnetic bearing system. It describes two appropriate fault-detection methods on the example of centrifugal pumps in magnetic bearings and shows how typical fault states occurring on these pumps can be detected and diagnosed. Prior to the fault detection the modeling of the magnetic bearing system is described. The investigated multi model method contains a bank of models representing the systems transfer behavior for the different fault. With this method the error between the outputs of the models and the output of the plant are provided as features for the fault diagnosis. Abalancing filter is described helping to separate the different features more clearly. Instead of computing the complete frequency behavior of the plant the transfer factor method uses the Goertzel algorithm to compute only significant discrete frequency points and provides the complex transfer factor as feature. It is shown that fault detection and diagnosis could be integrated within AMB systems. Both methods are well suited to provide reliable information about the system state.
BibTeX:
@inproceedings{ISMB12_69,
  author = {Hendrik Schaede and Norman Butzek and Stephan Rinderknecht},
  title = {Model Based Fault-Detection and -Diagnosis using Active Magnetic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_69.pdf}
}
2010 Jiang, K. and Zhu, C. Multi-Frequency Periodic Vibration Suppressing With FBLMS Algorithm in Active Magnetic Bearing-Rotor System Proceedings of ISMB12  
Abstract: In active magnetic bearing (AMB)-rotor system, a method for the multi-frequency periodic vibration suppressing is proposed by an adaptive structure with the finite-duration impulse response (FIR) filter. To cater for the requirement of the long duration impulse response filter arisen in the AMB-rotor system, the Fast Block Least Mean Square (FBLMS) algorithm is adopted to efficiently implement the computation of linear convolution and linear correlation at a computational cost far less than that of the conventional FIR filter of time domain. The unique feature of the FBLMS algorithm is characterized by no influence on the computational complexity, regardless of the number of the vibration frequency components within the range of sampling frequency. The convergence rate of each frequency component can be adjusted by assigning the individual step size parameter for each filter weight. Furthermore, each harmonic component of the vibration can be addressed respectively or together. The experimental results of the reciprocating simulating disturbance test and the rotating harmonic vibration test show that the proposed adaptive structure with the FBLMS algorithm can achieve the good effectiveness for suppressing the multi-frequency periodic vibration.
BibTeX:
@inproceedings{ISMB12_70,
  author = {Kejian Jiang and Chuangsheng Zhu },
  title = {Multi-Frequency Periodic Vibration Suppressing With FBLMS Algorithm in Active Magnetic Bearing-Rotor System },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_70.pdf}
}
2010 Reichert, T., Nussbaumer, T. and Kolar, J.W. Performance Comparison of Bearingless Motor Topologies in Exterior Rotor Construction Proceedings of ISMB12  
Abstract: This paper presents several feasible slot/pole combinations for a bearingless motor in exterior rotor construction. Due to the limited available stator space, the slot number of the stator has to be chosen small in order to provide sufficient winding space. The characteristics of each possible topology are discussed in great detail and for each setup the optimal design parameters are derived using 3D-FEM analysis. In the end, a fair comparison between the presented topologies is undertaken and the optimal motor topology is implemented in a real-size prototype setup.
BibTeX:
@inproceedings{ISMB12_71,
  author = {Thomas Reichert and Thomas Nussbaumer and Johann W. Kolar},
  title = {Performance Comparison of Bearingless Motor Topologies in Exterior Rotor Construction },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_71.pdf}
}
2010 Niemann, A. and van Schoor, G. Self-Sensing Algorithm for Active Magnetic Bearings; Using Direct Current Measurements Proceedings of ISMB12  
Abstract: In the field of active magnetic bearings (AMBs) the self-sensing theme attracts attention due to the ongoing drive for compact integration and cost reduction. Self-sensing makes use of the AMB’s actuator to sense the position and to convert electrical energy to mechanical energy. The aim of the direct current measurement method (DCM) is to reduce phase shift produced by demodulation methods used in the past. The DCM self-sensing scheme makes use of a specific PWM switching method, which enables the estimation of the rotor position by only measuring the power amplifier ripple current. The DCM technique also has the added benefit of less sensitivity for cross-coupling effects. In this paper the PWM switching method, the method used to extract the current ripple and scaling are discussed. Simulations are done on a transient AMB model which resembles the physical system and practical results are obtained from the practical implementations.
BibTeX:
@inproceedings{ISMB12_72,
  author = {Andre Niemann and George van Schoor},
  title = {Self-Sensing Algorithm for Active Magnetic Bearings; Using Direct Current Measurements},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_72.pdf}
}
2010 Zhou, Y., Zhao, J., Xu, Y. and Sun, Z. The Preliminary Study of Reliability of AMB System with FTA Method Proceedings of ISMB12  
Abstract: Because of a lot of advantages, Active Magnetic Bearing (AMB) is widely applied in many fields especially for high-speed rotary machines. The reliability of the system is one of the most important indicators to measure AMB’s performance. With the way of Fault Tree Analysis, the potential probability of the whole system broken down can be calculated, which could provide some theory basis for the designer.
BibTeX:
@inproceedings{ISMB12_73,
  author = {Yan Zhou and JIngjing Zhao and Yang Xu and Zhuo Sun },
  title = {The Preliminary Study of Reliability of AMB System with FTA Method },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_73.pdf}
}
2010 Xin, G., Zhengang, S., Yang, X. and Lei, S. Research Status and Development of Fault Diagnosis for Active Magnetic Bearings Proceedings of ISMB12  
Abstract: Active magnetic bearings (AMB), a typical mechatronic product, have been successfully applied in industrial turbo machinery. Their main advantages are high speed, non-contact, no friction without lubrication, low noise, low power consumption, which give magnetic bearings broad application prospects. If magnetic bearings are to be applied to industry, the problems of condition monitoring and fault diagnosis must be solved. This paper analyzes the basic principles of fault diagnosis and fault diagnosis technology for rotating machinery, introduces the status quo of fault diagnosis for magnetic bearings, and proposes research directions and applications in the future.
BibTeX:
@inproceedings{ISMB12_74,
  author = {Gao Xin and Shi Zhengang and Xu Yang and Shi Lei},
  title = {Research Status and Development of Fault Diagnosis for Active Magnetic Bearings },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_74.pdf}
}
2010 Zürcher, F., Nussbaumer, T., Walter, S., Wegmüller, C. and Kolar, J.W. Comparison of Different Control Concepts for Bearingless Brushless Motors Proceedings of ISMB12  
Abstract: Bearingless motors offer various advantages compared to classical motors with mechanical bearings. However, they make great demands on the control algorithms. Due to the availability of very fast low-cost DSP, a lot of new control strategies can be implemented, which offer a lot of different benefits. In this paper, various control algorithms are compared regarding adequate criteria.
BibTeX:
@inproceedings{ISMB12_75,
  author = {Franz Zürcher and Thomas Nussbaumer and Stefan Walter and Christoph Wegmüller and Johann W. Kolar},
  title = {Comparison of Different Control Concepts for Bearingless Brushless Motors },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_75.pdf}
}
2010 Jan, Z., Bronislaw, T. and Dawid, W. Eddy Current Influence on the Parameters of Active Magnetic Bearing Proceedings of ISMB12  
Abstract: In this work, a symmetrical 8-pole (AMB8) magnetic bearing has been analyzed. The 3D Finite Element Method (FEM) was used for magnetic field computations and nonlinear boundary problem was investigated. We describe discretization process for the AMB modeling, [1]. The power losses and the force of the magnetic suspension have been calculated.
BibTeX:
@inproceedings{ISMB12_76,
  author = {Zimon Jan and Tomczuk Bronislaw and Wajnert Dawid},
  title = {Eddy Current Influence on the Parameters of Active Magnetic Bearing },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_76.pdf}
}
2010 Baumann, K., Dohnal, F. and Markert, R. Active Magnetic Bearings as Actuators and Sensor in Journal Bearing Measurements Proceedings of ISMB12  
Abstract: The present paper shows the successful usage of active magnetic bearings (AMBs) to identify the dynamic characteristics of journal bearings in the frequency domain. A test rig is operated using two AMBs supporting a rigid rotor with a centric journal bearing. An identification procedure for the stiffness and damping coefficients of journal bearings is presented. This procedure incorporates the successful application of AMBs for positioning, supporting, sensing and actuating the rotor simultaneously. For identification the real excitation force is needed. Two methods to derive a force-current-position relationship are outlined and compared: an idealized mathematical relation and a measured force-current-position map. Finally, results for applying the pre-measured map and an example of the identified stiffness and damping coefficients are given.
BibTeX:
@inproceedings{ISMB12_77,
  author = {Katrin Baumann and Fadi Dohnal and Richard Markert},
  title = {Active Magnetic Bearings as Actuators and Sensor in Journal Bearing Measurements },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_77.pdf}
}
2010 Wiedemann, D., Koch, U. and Ulbrich, H. Development of Magnetic Reluctance Actuators for Vibration Excitation Proceedings of ISMB12  
Abstract: The development and application of electromagnetic reluctance actuators for vibration excitation are presented. Main advantages are a compact and robust design with low thermal losses. The paper proposes a polarized actuator topology and describes the design procedure. An analytical method based on magnetic networks allows for a fast determination of machine parameters. finite element computations are carried out for a detailed magnetic circuit design. The combination of both methods leads to a straightforward development process for controlled reluctance actuators.
BibTeX:
@inproceedings{ISMB12_78,
  author = {Daniel Wiedemann and Ulrich Koch and Heinz Ulbrich},
  title = {Development of Magnetic Reluctance Actuators for Vibration Excitation },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_78.pdf}
}
2010 Chen, J., Liu, K., Xiao, K., Wang, H. and Ruan, Y. Analysis of Unbalanced Force for Flywheel Energy Storage System Based on Active Magnetic Bearing Considering Rotor Eccentricity Effects Proceedings of ISMB12  
Abstract: Flywheel energy storage system(FESS) based on active magnetic bearing(AMB) can be used to generate impulse electric power. The unbalanced forces considering rotor eccentricity need to be calculateded, especially when the discharging current is high. This paper investigates the unbalanced forces in FESS considering rotor eccentricity. The analytic solution for the magnetic flux density distribution in the airgap region is used to calculate the unbalanced Lorentz forces and magnetic forces, which are compared with that of finite element method(FEM). The results show that the unbalanced forces should be calculated for FESS to guarantee the flywheel safe whirling and provide reference to the control system design of AMB.
BibTeX:
@inproceedings{ISMB12_79,
  author = {Junfeng Chen and Kun Liu and Kai Xiao and Haoze Wang and Yigao Ruan },
  title = {Analysis of Unbalanced Force for Flywheel Energy Storage System Based on Active Magnetic Bearing Considering Rotor Eccentricity Effects },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_79.pdf}
}
2010 Dimond, T., Rockwell, R., Simmons, G. and Allaire, P. Comparison of Load Capacity and Inductance for Common Active Magnetic Bearings Designs Proceedings of ISMB12  
Abstract: Active magnetic bearings have become more popular as an alternative to fluid-film or rolling element bearings in rotating machinery. They have also become a method for force excitation for rotordynamic experiments, including system identification experiments. The current work considers alternate active magnetic bearing designs for a fluid film bearing test rig. The three designs considered include a conventional 8-pole design with equal widths, a 12-pole bearing with e-core quadrants, and a 16-pole alternate with two exterior auxiliary poles and two interior main poles per quadrant. Several previous studies have considered equal pole widths in optimizing magnetic bearing stator geometry. While not an optimization study, this analysis presents a comparison of popular AMB geometries commonly used in industrial applications. The load capacity, magnetic field energy, and inductance were compared. The 16-pole bearing was shown to have the highest load capacity of the three designs. The inductive load also increased with increasing number of poles. The 12 and 16 pole designs, with reduced auxiliary pole width, also exhibited better containment of the magnetic flux within each active magnetic bearing quadrant, which simplifies the control problem. The results are of use for AMB designers and provide guidance for future stator optimization studies.
BibTeX:
@inproceedings{ISMB12_80,
  author = {Timothy Dimond and Robert Rockwell and Gregory Simmons and Paul Allaire},
  title = {Comparison of Load Capacity and Inductance for Common Active Magnetic Bearings Designs },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_80.pdf}
}
2010 Grabner, H., Reisinger, M., Silber, S., Amrhein, W., Redemann, C. and Jenckel, P. Nonlinear Feedback Control of a Five Axes Active Magnetic Bearing Proceedings of ISMB12  
Abstract: The demands on active magnetic bearings concerning performance as well as costs are high. The proposed five axes active magnetic bearing has a compact design and runs with simplified power electronics. Owing to the nonlinearity of the plant, the use of linear control design methods alone is not suitable for achieving a high operation performance. This paper introduces a novel combined radial and axial position control algorithm. Experimental results demonstrate the effectiveness of the proposed approach.
BibTeX:
@inproceedings{ISMB12_81,
  author = {Herbert Grabner and Martin Reisinger and Siegfried Silber and Wolfgang Amrhein and Christian Redemann and Peter Jenckel},
  title = {Nonlinear Feedback Control of a Five Axes Active Magnetic Bearing },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_81.pdf}
}
2010 Chinan, P., Hijikata, W. and Shinshi, T. Fault-Tolerance for a Centrifugal Blood Pump using a Two-DOF Controlled Magnetic Bearing Proceedings of ISMB12  
Abstract: In our laboratory, an implantable centrifugal blood pump (CBP) with a two degrees-of-freedom controlled magnetic bearing (MB) to support the impeller without contact has been developed to assist the pumping function of a weakened heart ventricle. In order to maintain the function of the CBP after damage to the electromagnets (EMs) of the MB, fault-tolerant strategies for the CBP are proposed in this study. Using a redundant design of the MB, the magnetic levitation of the impeller was maintained with damage to up to two out of a total four EMs of the MB. Furthermore, with damage to three EMs, contact-free support of the impeller was also achieved by using hydrodynamic and electromagnetic forces.
BibTeX:
@inproceedings{ISMB12_82,
  author = {Pai Chinan and Wataru Hijikata and Tadahiko Shinshi},
  title = {Fault-Tolerance for a Centrifugal Blood Pump using a Two-DOF Controlled Magnetic Bearing },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_82.pdf}
}
2010 Marth, E., Jungmayr, G. and Amrhein, W. Influence of Viscoelastic Elements on Magnetically Passive Stabilized Degrees of Freedom Proceedings of ISMB12  
Abstract: Magnetic bearing technology is one of the most promising future technologies in the area of electrical drive systems. Due to the contact-free rotor suspension numerous advantages arise. The utilization of passive magnetic bearings is a very effective way of realizing magnetic levitation. Thereby, systems with a minimal constructive complexity can be obtained. However, such constructions have a main drawback: the damping of the passively stabilized degrees of freedom is negligibly small. External excitations or resonant vibrations may cause considerable damage to the bearing system. This study describes an effective way to damp vibrations by means of viscoelastic elements. The mathematical formulation of the overall dynamic system is derived and the analytic results are verified by measurements.
BibTeX:
@inproceedings{ISMB12_83,
  author = {Edmund Marth and Gerald Jungmayr and Wolfgang Amrhein},
  title = {Influence of Viscoelastic Elements on Magnetically Passive Stabilized Degrees of Freedom },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_83.pdf}
}
2010 Jungmayr, G., Marth, E., Amrhein, W. and Weidenholzer, G. Influence of Viscoelastic Damping Elements on Magnetically Active Stabilized Degrees of Freedom Proceedings of ISMB12  
Abstract: The application of viscoelastic damping elements is well suited for the minimization of radial and tilt vibrations of rotors featuring radial passive magnetic bearings. This paper discusses the influence of the damping element on the axial, magnetically active stabilized degree of freedom of such systems. The stabilizable axial excitations are calculated for the case of a rigid and for the case of an elastical stator-housing connection and are verified by means of measurements. Furthermore, the influence of the control parameters is discussed. In order to acquire an optimal stability against external vibrations, a genetic optimization of the controller parameters was carried out.
BibTeX:
@inproceedings{ISMB12_84,
  author = {Gerald Jungmayr and Edmund Marth and Wolfgang Amrhein and Günther Weidenholzer},
  title = {Influence of Viscoelastic Damping Elements on Magnetically Active Stabilized Degrees of Freedom },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_84.pdf}
}
2010 Osa, M., Masuzawa, T. and Tatsumi, E. Miniaturized Magnetically Levitated Motor for Pediatric Artificial Heart Proceedings of ISMB12  
Abstract: An axially levitated motor has been developed for use in pediatric artificial hearts. The developed axially levitated motor consists of a top stator, bottom stator, and levitated rotor impeller. The developed motor has an outer diameter of 24 mm and a total length of 41 mm. The motor was designed based on three dimensional magnetic field analysis. The target axial attractive force of the levitated motor is 10 N, and a torque of 1 mNm at a rotational speed of 4000 rpm. The developed motor produces an axial attractive force of 10.6 N, and a torque of 5.8 mNm respectively. Experimental results display sufficient magnetic suspension capability and rotational performance of the levitation system for a pediatric ventricular assist device.
BibTeX:
@inproceedings{ISMB12_85,
  author = {Masahiro Osa and Toru Masuzawa and Eisuke Tatsumi},
  title = {Miniaturized Magnetically Levitated Motor for Pediatric Artificial Heart },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_85.pdf}
}
2010 Gronek, M., Worlitz, F. and Lindenau, B.E. Experimental Investigations on the Properties and Dynamic Behaviour of a Hybrid Bearing System for Turbo Machines Proceedings of ISMB12  
Abstract: Within the frame of an international research program that was supported by the European Commission, one subtask was to determine the dynamic behaviour of rotating shafts of turbo machines using a Hybrid Magnetic Bearing Concept (HMBC). This HMBC denotes the combination of Active Magnetic Bearings (AMB) with an additional Permanent Magnetic Bearing (PMB). For the present investigations a permanent magnetic radial shear force bearing was used. Due to their characteristics the conventional active magnetic suspension and the permanent magnetic support affect each other. This mutual action has to be considered at the benefit analysis of a hybrid bearing system. This contribution outlines the scientific approach of these studies. The overarching objective was to make the results sustainable to use. Therefore validated models will be necessary that are able to recreate the dynamic behaviour of a magnetic suspended rotor with the support of an additional permanent magnetic bearing. The basis of this approach is the application of methods of theoretical and experimental modelling. The validation of the created models was made with reference to experimental tests on the FLP 500 test facility in Zittau, Germany. For the necessary experiments the completely AMB-supported test rig was equipped with an additional permanent magnetic radial bearing.
BibTeX:
@inproceedings{ISMB12_86,
  author = {Martin Gronek and Frank Worlitz and Bernd E. Lindenau},
  title = {Experimental Investigations on the Properties and Dynamic Behaviour of a Hybrid Bearing System for Turbo Machines },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_86.pdf}
}
2010 Rottenbach, T. and Worlitz, F. Revision of the AMB-Supported Coolant Pump after the Long-Term Operation in the Power Plant Proceedings of ISMB12  
Abstract: with active magnetic bearings (AMBs). This AMB-supported pump was installed and tested in the inter-cooling circuit of a 500 MW block-unit in a lignite power station as a demonstration plant. The aim was to proof the suitability of magnetic bearings for using on turbo machines under operation conditions in a power station [1]. After the phase of commissioning the pump was used in a long term operation as the main operation pump [2]. The pump was subjected to a revision after an approx. three and a half year running time. Thereby the condition of the pump, especially of the bearing components was checked. The disassembling of the pump was covered by some difficulties, caused by corrosion of mechanical parts. In addition with detected damages on single components, countermeasures for prevention had to be derived. Furthermore design criterions, applicable materials and requirements e. g. for the shaft seals can be concluded. This report gives an insight into the increase of experience and knowledge collected during the revision of the AMB-supported coolant pump.
BibTeX:
@inproceedings{ISMB12_87,
  author = {Torsten Rottenbach and Frank Worlitz},
  title = {Revision of the AMB-Supported Coolant Pump after the Long-Term Operation in the Power Plant },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_87.pdf}
}
2010 Imoberdorf, P., Nussbaumer, T. and Kolar, J.W. Analytical Model of Current-Force Characteristics of a Combined Radial-Axial Magnetic Bearing Proceedings of ISMB12  
Abstract: In today’s industry high-speed and high-power-density drives are attracting much interest, e.g. for applications with mesoscale gas turbine generator systems or turbocompressors for fuel cells. In all high-speed drive systems the bearing technology is a key component. Therefore, this paper presents the analysis of an active magnetic bearing suitable for a permanent magnet machine, being part of a high-speed electrical drive system. The analysis has its focus on the detailed characterization of the magnetic forces, the coupling between the different axes and the verification of the theoretical considerations by means of 3D-FEM simulations. To understand the behavior of the bearing forces is needed to implement the position control to the prototype of the bearing system, which already has been built.
BibTeX:
@inproceedings{ISMB12_88,
  author = {Philipp Imoberdorf and Thomas Nussbaumer and Johann W. Kolar},
  title = {Analytical Model of Current-Force Characteristics of a Combined Radial-Axial Magnetic Bearing },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_88.pdf}
}
2010 Xu, Y., Yu, H., Zhao, L. and Yu, S. Development of a Magnetic Bearing Rotor Dynamics Analysis Software Package Proceedings of ISMB12  
Abstract: During the design and research stage of magnetic bearings, often need to solve numerous of the rotor dynamics problems. Sometimes, to process these issues quickly and get preliminary conclusions is very help for its design. Just for this reason, a finite element software package running in the ANSYS environment is designed. It could highly improve efficiency through some simplifications of analysis, and could still achieve acceptable accuracy.
BibTeX:
@inproceedings{ISMB12_89,
  author = {Yang Xu and Hao Yu and Lei Zhao and Suyuan Yu },
  title = {Development of a Magnetic Bearing Rotor Dynamics Analysis Software Package },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_89.pdf}
}
2010 Suzuki, T., Ueno, S. and Takeda, T. Development of a Vacuum Pump using Axial-Gap Self-Bearing Motor and Superconducting Magnetic Bearing Proceedings of ISMB12  
Abstract: In recent years, superconducting technology has rapidly advanced and has been applied to several devices like magnetoencephalography(MEG) and magnetic resonance imaging(MRI). Superconductivity occur at extremely low temperatures, hence liquid helium is always used to achieve it. In order to conserve liquid helium, a circulation system has been recently developed. In the developed system, a pump will be used for cooling liquid helium. In addition, this pump will improve the capability of medical devices that use superconducting coils. In this paper, we propose the development of a vacuum pump that can be used at extremely low temperatures by using axial self bearing motor (ASBM) and superconducting magnetic bearing (SMB). The pump has the advantages of no friction, as there is no contact, high efficiency and no maintenance. The design of the pump is presented, and the control method is theoretically and practically analyzed. We performed an experiment to confirm that the reliability of the proposed vacuum pump.
BibTeX:
@inproceedings{ISMB12_90,
  author = {Tatsushi Suzuki and Satoshi Ueno and Tsunehiro Takeda},
  title = {Development of a Vacuum Pump using Axial-Gap Self-Bearing Motor and Superconducting Magnetic Bearing },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_90.pdf}
}
2010 Mitterhofer, H., Amrhein, W. and Gruber, W. Towards High Speed Bearingless Drives Proceedings of ISMB12  
Abstract: The design of a high speed bearingless drive shows special requirements concerning topology and loss minimization. This paper discusses the use of a bearingless disc motor for such a purpose. The effects of the selected geometric dimensions on the ability to produce passive and active bearing forces are studied in 3D-FEM simulations. Furthermore, a toroid winding, suitable for the chosen flat motor geometry, and an adequate 5-phase winding scheme are proposed. In an analytical part, the copper losses due to the motor and bearing currents, as well as due to the external rotor magnet field are calculated. The results lead to the selection of a preferable litz wire gauge which is finally used in the construction of a first motor prototype.
BibTeX:
@inproceedings{ISMB12_91,
  author = {Hubert Mitterhofer and Wolfgang Amrhein and Wolfgang Gruber},
  title = {Towards High Speed Bearingless Drives },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_91.pdf}
}
2010 Mizuno, T., Furutachi, M., Ishino, Y. and Takasaki, M. Proposal of Wind Tunnel for Spinning Body Using Magnetic Suspension Proceedings of ISMB12  
Abstract: A wind-tunnel system for spinning body is proposed to measure hydrodynamic forces acting on the body. In the proposed system, the body is suspended and rotated by electromagnets. The forces are measured from the control signal for suspension. An experimental apparatus is fabricated to demonstrate the feasibility. In the apparatus, eight electromagnets are placed around the wind-tunnel. A photo sensor using four lens and phototransistors was manufactured for detecting three-dimensional positions of the body. In the experiment, stable suspension and three-dimensional positioning of the body were achieved. Spinning of the body was realized by superimposing two-phase AC signals on the control signal. The fluid drag force was measured from the control input of PID controller. It was ascertained that the drag force increases as the flow velocity increases.
BibTeX:
@inproceedings{ISMB12_92,
  author = {Takeshi Mizuno and Munehiro Furutachi and Yuji Ishino and Masaya Takasaki},
  title = {Proposal of Wind Tunnel for Spinning Body Using Magnetic Suspension },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_92.pdf}
}
2010 Hynynen, K.M., Jastrzebski, R.P. and Smirnov, A. Experimental Analysis of Frequency Response Function Estimation Methods for Active Magnetic Bearing Rotor System Proceedings of ISMB12  
Abstract: System identification can be used in automated retuning of an active magnetic bearing (AMB) rotor system during commissioning. In the case of good signal-to-noise ratio (SNR), the identification measurements are more time effective using multisine excitation than stepped sine excitation. A multisine signal contains selected frequencies in the desired frequency range. Since in multisine excitation the signal distributes the power over F frequencies, the SNR of the measurement deteriorates. The SNR is improved by averaging the measured frequency response function (FRF) over several measurements. The purpose of this study is to investigate the suitability of different frequency response function estimators for an AMB rotor system identification. The results show that the most accurate estimator for this setup with non-synchronous measurements and the excitation used, is a joint-input-output estimator.
BibTeX:
@inproceedings{ISMB12_94,
  author = {Katja M. Hynynen and Rafal P. Jastrzebski and Alexander Smirnov},
  title = {Experimental Analysis of Frequency Response Function Estimation Methods for Active Magnetic Bearing Rotor System },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_94.pdf}
}
2010 da Costa, E.A., Chabu, I.E. and da Cruz, J.J. Active Magnetic Bearing for Tubular Linear Induction Motor Applied to Onshore Oil Exploitation Proceedings of ISMB12  
Abstract: A tubular linear induction motor applied to onshore oil exploitation was proposed recently. Its purpose is to directly drive the sucker-rod pump installed in the down hole of the oil well. In continuing the research an active magnetic bearing (AMB) was developed and applied to the motor in substitution to the existing mechanical bearing. Instead of the usual eight-pole AMB, a different concept is adopted where a DC-excited primitive bearingless machine is used as a magnetic bearing. The magnetic bearing levitation control is executed by a digital controller using an AD/DA converter and a control algorithm implemented in FPGA hardware. A linear model is written to describe its dynamics. In this work the AMB system is studied with particular emphasis to the experimental results obtained with the prototype in operation. Tests performed on this prototype show that the AMB can be an interesting alternative to be considered in this context.
BibTeX:
@inproceedings{ISMB12_97,
  author = {Eduardo Alves da Costa and Ivan Eduardo Chabu and Jose Jaime da Cruz},
  title = {Active Magnetic Bearing for Tubular Linear Induction Motor Applied to Onshore Oil Exploitation },
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_97.pdf}
}
2010 Bleuler, H. Recent Activities in European AMB Research Proceedings of ISMB12  
Abstract: This presentation will give an overview of current activities of research institutes as well as industrial actors in the magnetic bearing field. The technical domains covered will be on various active magnetic bearing projects, on passive magnetic bearings and also on superconducting rotor bearings These various types of AMB will be placed in the context of a basic classification of magnetic levitation principles. Finally some activities on diamagnetic levitation will be included as well. European research on rotor bearings is mainly being done in France, Germany, Italy and Switzerland, examples from all of these will be presented. The application fields cover various industrial activities, biomedical devices, energy and micromanipulation.
BibTeX:
@inproceedings{ISMB12_key01,
  author = {Hannes Bleuler},
  title = {Recent Activities in European AMB Research},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_key01.pdf}
}
2010 Ueyama, H. and Taniguchi, M. Thermal Simulation of Rotating Machine Equipped with Active Magnetic Bearings Proceedings of ISMB12  
Abstract: Lately higher speed and higher power drive technology is more demanding in many industrial application such as several kinds of turbo machinery ex. compressor, expander and generator relating to various kind of gas processing. Active magnetic bearing should be a one of potential device to support such high power density rotor. On the other hands, high power densitywill induce several technical problems. One of these technical problems is thermal problem. Hence the rotor supported by active magnetic bearing can only dissipate generated heat by means of convection and radiation (no conduction), elongation of the rotor may cause serious change in mechanical air gap, especially axial air gap between rotor and touch down bearings shall be carefully considered. For handling this problem, thermal analysis of entire machine is needed.[1] The mathematical model of entire machine shall be consisting of rotor and all of non-rotating components such as activemagnetic bearing’s actuator,motor stator, housing and cooling jacket. Further more it is better to simulate transient thermal behavior of each machine components, author has developedMatlab/simlink based simulation tool for this purpose.
BibTeX:
@inproceedings{ISMB12_key02,
  author = {Hirochika Ueyama and Manabu Taniguchi},
  title = {Thermal Simulation of Rotating Machine Equipped with Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_key02.pdf}
}
2010 Allaire, P. Design and Analysis of Magnetic Suspension for New Artificial Heart Proceedings of ISMB12  
Abstract: Artificial hearts have been developed with magnetic suspension for the last 20 years, starting at the University of Virginia. A new axial flow path, magnetically suspended artificial heart-the Lifeflow-is currently under development. The magnetic suspension consists of two permanent magnet biased active radial bearings and an axial permanent magnet thrust bearing. The radial bearings are six pole bearings which employ self sensing. The pump rotates at approximately 7,000 rpm with a flow rate of approximately 5 liters/min and a pressure rise of 100 mm of Hg. The magnetic suspension system consumes only about 2 watts due to the combined use of the permanent and active magnetic bearings. A finite element analysis has been carried out to determine the magnetic properties of the magnetic suspension system. The thrust bearing has been constructed to not require a thrust disk-which permits a very streamlined flow path for the blood through the pump. The properties of the permanent magnetic thrust bearing-magnetic flux, load capacity, axial/radial stiffness have been determined. For the active radial bearings, the bias flux, radial load capacity, open loop stiffness and current gain have been calculated. A magnetic suspension test rig has been constructed and experimental tests are ongoing. One of the features of most current artificial heart pumps available for human implantation is that only the motor current is available to monitor the operating condition in the pump when implanted. This low level of monitoring is not sufficient to effectively monitor heart pump performance when implanted. For example, many current artificial heart pumps are subject to thrombus formation which can lead to strokes. New features of the Lifeflow pump include pressure sensors to determine the pressure at the inlet and the discharge regions of the pump, impeller radial displacements during implanted pump operation. These operating system measurements, as well as motor currents, will be sent via wifi to the monitoring medical team. It is expected that active, remote monitoring of these pumps will assist in maintaining safe pump operation.
BibTeX:
@inproceedings{ISMB12_key03,
  author = {Paul Allaire},
  title = {Design and Analysis of Magnetic Suspension for New Artificial Heart},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_key03.pdf}
}
2010 Li, L. New Displacement-Sensing Techniques for Magnetic Bearings Proceedings of ISMB12  
Abstract: We report three new displacement-sensing techniques for magnetic bearings. An outstanding feature is that a carrier wave or demodulation is not needed, while performances comparable to that of existing techniques are obtained. The first is based on eddy-current energy loss, and has very simple sensor electronics. The second is capacitance type. It works by cyclic charge and discharge of a capacitor, and allows for direct fabrication on printed circuit board. The third is inductance type. It permits sensing across a 0.5-mm thickness wall of non-magnetic stainless-steel material, while the bandwidth is a few kHz.
BibTeX:
@inproceedings{ISMB12_key04,
  author = {Lichuan Li},
  title = {New Displacement-Sensing Techniques for Magnetic Bearings},
  booktitle = {Proceedings of ISMB12},
  year = {2010},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb12/ismb12_submission_key04.pdf}
}
2008 Murakami, S., Ikeda, T. and Watanabe, T. Numerical Simulations and Experiments on Vibration at Major Critical Speed of Rotor Suspended by Magnetic Bearing-Influence of Decrement of Magnetic Force Due to Eddy Current Caused by Rotation Proceedings of ISMB11  
Abstract: Vibration characteristic of a rotor supported by a PID controlled magnetic bearing is investigated. The differential equation of motion is derived with nonlinearities of the magnetic force for the gap, the current, and the characteristics of a current ampli?er together with the decrement of magnetic force due to surface eddy current caused by rotation of the rotor. The in?uence of the rotational speed on the magnetic force is approximated by a fractional function and the coef?cients are determined by experiments. By this approximation, the resonance curves for a major critical speed by the shooting method have good agreements with the experimental results.
BibTeX:
@inproceedings{ISMB11_1,
  author = {Shin Murakami and Takashi Ikeda and Tsubasa Watanabe},
  title = {Numerical Simulations and Experiments on Vibration at Major Critical Speed of Rotor Suspended by Magnetic Bearing-Influence of Decrement of Magnetic Force Due to Eddy Current Caused by Rotation},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_1.pdf}
}
2008 Paiva, J.A.D., Salazar, A.O., Maitelli, A.L. and Stephan, R.M. Performance Improvement of a Split Winding Bearingless Induction Machine Based on A Neural Network Flux Observer Proceedings of ISMB11  
Abstract: This work describes the performance improvement of a 4 poles 1,1 kW split winding bearingless induction machine based on a neural rotor flux observer. The system control executes simultaneously the vector speed control, the radial positioning control and the stator winding current control. The neural flux observer compensates for parameter variations due to temperature changes or due to the rotor magnetic saturation. A program developed in the ANSI C language executes all the system control. The used DSP resources are the Analog/Digital converters, the PWM outputs and the parallel and RS-232 serial interfaces, which are responsible, respectively, for the DSP programming and the data capture through the supervisory system. Comparisons with a fixed parameter observer validate the proposed method.
BibTeX:
@inproceedings{ISMB11_10,
  author = {Jose Alvaro De Paiva and Andres Ortiz Salazar and Andre Laurindo Maitelli and Richard Magdalena Stephan},
  title = {Performance Improvement of a Split Winding Bearingless Induction Machine Based on A Neural Network Flux Observer},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_10.pdf}
}
2008 Ranft, E.O. and van Schoor, G. A Coupled Reluctance Network Approach to Self-Sensing Proceedings of ISMB11  
Abstract: Although self-sensing is not a new concept and the topic has been researched in the past, it remains a challenge. Self-sensing performance is degraded due to problems such as magnetic cross-coupling, eddy currents, saturation and high losses, to name but a few. In this paper the amplitude modulation self-sensing approach using the switching amplifier ripple as high frequency source is adopted. A coupled reluctance network model (RNM) is developed which models the coil impedance at the switching frequency. The model is refined, to accurately include the mentioned degrading effects, and incorporated into a multiple input multiple output (MIMO) parameter estimation self-sensing scheme. Simulation results show that it is possible to address saturation and magnetic cross-coupling with the RNM incorporated into a MIMO parameter estimation scheme. System sensitivity levels satisfactory for long term operation are achieved.
BibTeX:
@inproceedings{ISMB11_100,
  author = {Eugen Otto Ranft and George van Schoor},
  title = {A Coupled Reluctance Network Approach to Self-Sensing},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_100.pdf}
}
2008 Sawicki, J.T. and Maslen, E.H. Toward Automated AMB Controller Tuning: Progress in Identification and Synthesis Proceedings of ISMB11  
Abstract: A significant impediment to low cost commercial deployment of magnetic bearing systems in many applications is the engineering process of tuning. In applications where the dynamics of the platform contribute significantly to overall system dynamics, AMB tuning in the vendor factory may not be sufficient to provide satisfactory performance once installed. In this case, on-site retuning is done ?by hand? by a skilled engineer and the associated cost can be substantial. In addition, later alterations in the plant, the process, or the internal machine dynamics may dictate retuning of the AMB controller, again requiring costly engineering intervention. In this paper, we examine the general characteristics of the plant that govern the requirements of an automated tuning process. The AMB machine tool spindle will serve as an example to illustrate results and outline the approach to the robust control model validation problem.
BibTeX:
@inproceedings{ISMB11_11,
  author = {Jerzy T. Sawicki and Eric H. Maslen},
  title = {Toward Automated AMB Controller Tuning: Progress in Identification and Synthesis},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_11.pdf}
}
2008 Tanaka, N., Watanabe, T. and Seto, K. Levitation and Vibration Control of a Flexible Rotor by Using Active Magnetic Bearing Proceedings of ISMB11  
Abstract: This paper presents a new modeling method and a control system design procedure for a flexible rotor with many elastic modes by using active magnetic bearings. The purpose of our research is to rotate the rotor for passing through critical speeds caused by flexible modes. To achieve this, it is necessary to control motion and vibration of the flexible rotor simultaneously. The new modeling method named as Extended Reduced Order Physical Model is presented to express its motion and vibration uniformly. By using this model, a PID (Proportional-Integral-Derivative) controller to levitate the rotor and a LQ (Linear-Quadratic) controller to suppress its vibration are designed.
BibTeX:
@inproceedings{ISMB11_12,
  author = {Naoyuki Tanaka and Toru Watanabe and Kazuto Seto},
  title = {Levitation and Vibration Control of a Flexible Rotor by Using Active Magnetic Bearing},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_12.pdf}
}
2008 Janssen, J., Paulides, J. and Lomonova, E. Passive Magnetic Suspension Limitations for Gravity Compensation Proceedings of ISMB11  
Abstract: The development of sophisticated advanced vibration isolation is important, since even the minutest vibrations have disastrous effects on the performance of static and moving parts in high-precision machines. This paper concerns with the isolation of these vibrations for a large static body in an advanced micro-lithographic system, where a passive/active electromagnetic solution is presented. In these configurations passive permanent magnets (PM) provide the gravity compensation and active electromagnets the accurate positioning. However, this paper only considers the applicability of a passive magnetic solution for this high force gravity compensation application, or, more specifically, the influence of various PM array topologies on the force density. Further, fast-solving analytical models will be presented and will consequently be used to illustrate the feasibility of using passive permanent magnets for gravity compensation in this demanding high precision industrial application.
BibTeX:
@inproceedings{ISMB11_13,
  author = {J.L.G. Janssen and J.J.H. Paulides and E. Lomonova},
  title = {Passive Magnetic Suspension Limitations for Gravity Compensation},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_13.pdf}
}
2008 Jose, S.A., Andre, P. and das Neves Vagner Modeling and Control of an Axial Magnetic Bearing for a Prototype of Electric Motor Supported by Radial Magnetic Bearings Proceedings of ISMB11  
Abstract: Research on magnetic bearings is being conducted in universities and research centers all over the world. Among the main advantages of the use of these devices are the reduction of friction losses and their corresponding necessity for maintenance. Magnetic bearings can already be found in rotating machines in medical, food, oil, and military industries. As to electric machines, the use of such electromagnets provides a natural instability to the system. Therefore, controllers become necessary to hold the rotor in an equilibrium position, without contact with the stator. In this work, modeling, implementation, and practical results of an axial position controller is presented. An axial controller has been designed to be implemented on an experimental prototype that consists of an induction motor, arranged in the horizontal position, already supported by radially controlled magnetic bearings. Different from other approaches, the experimental stiffness and damping observed along the axial direction, when only the radial magnetic bearings are acting, was taken into account for the controller design.
BibTeX:
@inproceedings{ISMB11_14,
  author = {Santisteban Andres Jose and Plaisant Andre and das Neves Vagner},
  title = {Modeling and Control of an Axial Magnetic Bearing for a Prototype of Electric Motor Supported by Radial Magnetic Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_14.pdf}
}
2008 Hu, Y., Wu, H., Wei, L. and Wang, X. Study on the Unbalance of Magnetic Suspended Rotor Based on Holospectrum Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_15,
  author = {Yefa Hu and Huachun Wu and Li Wei and Xiaoguang Wang},
  title = {Study on the Unbalance of Magnetic Suspended Rotor Based on Holospectrum},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_15.pdf}
}
2008 Chen, S.-L. and Hsu, S.-Y. Analysis and Control of a Three-Pole Permanent Magnet Type Bearingless Motor Proceedings of ISMB11  
Abstract: The active magnetic bearing (AMB) possesses several advantages such as no friction, high rotational speed, less energy loss, and long life span etc. In rotation application, however, it must be connected to a motor, which may degrade its performance. Bearingless motor is the combination of the active magnetic bearing and motor. It saves software and hardware facilities, resulting in lower costs. This paper mainly designed a three-pole permanent-magnet type bearingless motor, and analyzed the rotational magnetic field, magnetic force of the bearing, and resulting torque of the motor. Finally, we established system dynamic mathematical model. The controller design and numerical simulations are implemented, and reach the last target.
BibTeX:
@inproceedings{ISMB11_16,
  author = {Shyh-Leh Chen and Shang-Yu Hsu},
  title = {Analysis and Control of a Three-Pole Permanent Magnet Type Bearingless Motor},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_16.pdf}
}
2008 Nguyen, D.Q. and Ueno, S. Sensorless Speed Control of a Permanent Magnet Type Axial Gap Self-Bearing Motor Proceedings of ISMB11  
Abstract: This paper presents an analytical and experiment evaluation of sensorless speed vector control of a permanent magnet type axial gap self bearing motor, in which rotor speed and position are estimated by using state observer, not by using mechanical encoder or resolver... The approach is based on the estimation of the motor back-EMF (or induced voltage) through a state observer with help of measured stator currents and reference voltages. In order to achieve an accurate estimation of the rotor speed and position, adaptive gain of observer controller is proposed. The experiment is implemented based on dSpace1104 with two three phase inverters. Results confirm that axial force and rotating torque can be controlled independently and motor can get the good performance in steady state at the average and high speed range. <
BibTeX:
@inproceedings{ISMB11_17,
  author = {Dich Quang Nguyen and Satoshi Ueno},
  title = {Sensorless Speed Control of a Permanent Magnet Type Axial Gap Self-Bearing Motor},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_17.pdf}
}
2008 Nakano, Y., Asami, T., Asama, J., Chiba, A., Fukao, T., Hoshino, T. and Nakajima, A. Basic Characteristics of Improved Bearingless Motor with Passive Magnetic Bearings Proceedings of ISMB11  
Abstract: In this paper, basic characteristics of a bearingless motor with passive magnetic bearings (PMBs) are presented. A bearingless motor is actively controlled in two perpendicular radial movements, and is passively stable in the other three degrees of freedom, i.e., axial and conical movements. With PMBs, the stiffness is enhanced in axial and conical movements. To enhance stiffness, an improved machine has been designed. The experimental results of basic characteristics in the proposed machine are presented. The experimental results are compared to the calculated ones using three-dimensional finite element method (3D-FEM). The experimental results of the proposed machine with and without PMBs are compared. It is presented that a bearingless motor with PMBs has significantly enhanced the axial and conical stiffness.
BibTeX:
@inproceedings{ISMB11_18,
  author = {Yukiko Nakano and Tetsuro Asami and Junichi Asama and Akira Chiba and Tadashi Fukao and Takeshi Hoshino and Atsushi Nakajima},
  title = {Basic Characteristics of Improved Bearingless Motor with Passive Magnetic Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_18.pdf}
}
2008 Zürcher, F., Nussbaumer, T., Gruber, W. and Kolar, J.W. Comparison of 2- and 3-Phase Bearingless Slice Motor Concepts Proceedings of ISMB11  
Abstract: Several processes in chemical, pharmaceutical, biotechnology and semiconductor industry require contactless levitation and rotation through a hermetically closed process chamber. A highly interesting topology for these applications is the “bearingless slice motor” con-cept, where already some research has been done in the past, especially focusing on topology and implementa-tion issues. However, only little work has been done to evaluate the ideal number of motor phases. In this pa-per, a performance evaluation between 2-phase and 3-phase bearingless slice motor concepts is undertaken. It is shown, that 3-phase systems can supply almost the same power as adequate 2-phase systems and achieve nearly the same acceleration behavior, although they have significantly less complex power electronics.
BibTeX:
@inproceedings{ISMB11_19,
  author = {Franz Zürcher and Thomas Nussbaumer and Wolfgang Gruber and Johann Walter Kolar},
  title = {Comparison of 2- and 3-Phase Bearingless Slice Motor Concepts},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_19.pdf}
}
2008 Ooshima, M. and Kitada, H. Development of an Axial Magnetic Bearing for Vertical-Type Centrifugal Separators Proceedings of ISMB11  
Abstract: This paper presents a new axial magnetic bearing for the centrifugal separators, which are used to separate into liquids and solids in chemical, material industries, and so on. In order to separate much original liquid into the liquid and the solid for a short time, the centrifugal separators with large volume and large capability are required. To satisfy the requirements, the large axial magnetic bearing with the maximum axial magnetic force of 7,200 N is proposed. The features are as follows: 1) the magnetic field does not influence on the flow of the original liquid, and 2) the stiffness is relatively high also in the radial direction. The structure of the proposed axial magnetic force is shown and the control system configuration is also introduced. The optimal sizes of the electromagnets and permanent magnets are derived by the analysed results using Finite Element Method (FEM). The radial and axial forces are also computed by FEM for the rotor motion in the parallel and conical modes, respectively. It is confirmed that the enough suspension force is generated to support the rotor suspension part in the proposed axial magnetic bearing, which is quite suitable as the axial magnetic bearing in the vertical-type centrifugal separator.
BibTeX:
@inproceedings{ISMB11_2,
  author = {Masahide Ooshima and Hiroshi Kitada},
  title = {Development of an Axial Magnetic Bearing for Vertical-Type Centrifugal Separators},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_2.pdf}
}
2008 Laiho, A., Tammi, K., Orivuori, J., Sinervo, A., Zenger, K. and Arkkio, A. Electromechanical Interaction in Eccentric-Rotor Cage Induction Machine Equipped with a Self-Bearing Force Actuator Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_20,
  author = {Antti Laiho and Kari Tammi and Juha Orivuori and Anssi Sinervo and Kai Zenger and Antero Arkkio},
  title = {Electromechanical Interaction in Eccentric-Rotor Cage Induction Machine Equipped with a Self-Bearing Force Actuator},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_20.pdf}
}
2008 Ransom, D., Masala, A., Moore, J., Vannini, G. and Camatti, M. Numerical and Experimental Simulation of a Vertical High Speed Motorcompressor Rotor Drop onto Catcher Bearings Proceedings of ISMB11  
Abstract: A new research program was jointly set up between GE Oil&Gas and Southwest Research Institute (SwRI), to predict and test the dynamics of a vertical rotor drop on catcher bearings. A numerical tool able to account for flexible rotor and stator dynamics, catcher bearing stiffness and damping mechanism was developed. An experimental activity on a new vertical rotor test rig was carried out. A first analysis of numerical simulations and experimental analysis is presented in this paper.
BibTeX:
@inproceedings{ISMB11_21,
  author = {David Ransom and Andrea Masala and Jeff Moore and Giuseppe Vannini and Massimo Camatti},
  title = {Numerical and Experimental Simulation of a Vertical High Speed Motorcompressor Rotor Drop onto Catcher Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_21.pdf}
}
2008 Cade, I.S., Sahinkaya, M.N., Burrows, C.R. and Keogh, P.S. On the Design of an Active Auxiliary Bearing for Rotor/Magnetic Bearing Systems Proceedings of ISMB11  
Abstract: This paper considers the design of an actively controlled auxiliary bearing system for use with magnetic bearings. During rotor/auxiliary bearing contact large frictional contact forces can lead to significant thermal stresses. Furthermore, the nonlinear nature of the contact can induce unfavourable rotor dynamic behaviour. An active auxiliary bearing capable of reducing the contact forces and influencing the rotor dynamics during contact is proposed. Active auxiliary bearing design objectives include reducing the rotor / bearing contact forces during impact and influencing the rotor dynamics to prevent a trapped contact mode from becoming established. A piezo actuated system, using a closed hydraulic coupling, is presented. The dynamic performance of the actuators and hydraulic line are identified. In particular, the transfer function from actuator control signal to auxiliary bearing displacement is identified. Closed loop control of the active auxiliary bearing using local proportional integral differential control is also considered.
BibTeX:
@inproceedings{ISMB11_22,
  author = {Iain Stuart Cade and M. Necip Sahinkaya and Clifford R. Burrows and Patrick S. Keogh},
  title = {On the Design of an Active Auxiliary Bearing for Rotor/Magnetic Bearing Systems},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_22.pdf}
}
2008 Keogh, P.S., Sahinkaya, M.N., Burrows, C.R. and Cade, I.S. Rotor/Auxiliary Bearing Dynamic Contact Modes in Magnetic Bearing Systems Proceedings of ISMB11  
Abstract: Magnetic bearings systems usually incorporate auxiliary bearings so that rotor/stator contact is prevented. The rotor must then make contact with the auxiliary bearings if any clearance boundaries are exceeded. It is then possible for a rotor with a given unbalance condition to exhibit either contact free levitation or to become trapped in various contact modes. For passively mounted auxiliary bearings, the contact modes are determined by the system design parameters. However, it is now feasible to mount the auxiliary bearings in an active system using piezoelectric actuators. If closed loop control is applied, the mounting (e.g. stiffness/damping) characteristics may be varied on-line. The potential also exists to apply open-loop actuation to the auxiliary bearing to make the clearance domain variable. For example, appropriate synchronous translation of a circular auxiliary bearing may cause it to appear as having a different radius or to be elliptical to the rotor. The question that needs to be addressed is whether this is useful in the destabilisation of contact modes so that contact free levitation may be restored. This paper will investigate whether this is a feasible option.
BibTeX:
@inproceedings{ISMB11_23,
  author = {Patrick Sean Keogh and Mehmet Necip Sahinkaya and Clifford Robert Burrows and Iain Stuart Cade},
  title = {Rotor/Auxiliary Bearing Dynamic Contact Modes in Magnetic Bearing Systems},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_23.pdf}
}
2008 Younan, A., Dimond, T. and Allaire, P. Drop Analysis of Auxiliary Bearings in Fluid Film/Magnetic Bearing Supported Rotor Proceedings of ISMB11  
Abstract: The work focuses on the design of the auxiliary bearings for the primary magnetic system in a new fluid film bearing test rig. The design is unique since the rotor is supported by the central tested journal bearing along with the two magnetic bearings. A three mass model for the rig is used to conduct the transient analysis of the rotor drop. Hertz contact theory is used to describe the contact between the rotor and the inner race of the back-up bearings. The analysis included different sets of auxiliary bearings as well as different levels of damping.
BibTeX:
@inproceedings{ISMB11_24,
  author = {Amir Younan and Tim Dimond and Paul Allaire},
  title = {Drop Analysis of Auxiliary Bearings in Fluid Film/Magnetic Bearing Supported Rotor},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_24.pdf}
}
2008 Zhu, C. A Novel Controllable Back-up Bearing for Active Magnetic Bearings Proceedings of ISMB11  
Abstract: All high performances of active magnetic bearings (AMBs) greatly depend on the reliability of the AMBs in normal and emergency conditions. Since the loading capability of the AMBs is limited and the rotating rotor will drop to the stator when the current of the coils is suddenly cut off or some parts of the AMBs, such as sensor, control system, power amplifiers, fail. In order to improve the reliability of the AMBs, a parallel back-up support system, as part of the AMBs design, should be used. Therefore, the back-up bearing is one of key elements to use successfully the AMBs in the rotating machinery and to improve the reliability of the AMBs. In order to develop a good performance back-up bearing for the AMBs, a novel controllable back-up bearing consisted of a general back-up bearing and a controllable flexible support which is based on eddy-current principle is presented in this paper. After shown the basic structure and principle of the novel controllable back-up bearing, the dynamic behaviors of the controllable back-up bearing with a fixed clearance ball bearing to improve the dropping dynamics after the AMBs failure are experimentally investigated, and the effectiveness of the novel controllable back-up bearing in controlling the transient vibration during rotor dropping is validated. It is shown that the dynamic behaviors of the novel controllable back-up bearing can be controlled and the novel controllable back-up bearing can greatly suppress the transient vibration during rotor dropping.
BibTeX:
@inproceedings{ISMB11_25,
  author = {Changsheng Zhu},
  title = {A Novel Controllable Back-up Bearing for Active Magnetic Bearings },
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_25.pdf}
}
2008 Lee, K.-C., Moon, J.-W., Jeong, Y.-H., Kang, D.-W., Koo, D.-H., Na, U.-J., Lee, S.-H. and Lee, M.-C. Digital Control of Magnetic Levitation for Contactless Delivery Applications Proceedings of ISMB11  
Abstract: In recent semiconductor making processes, high-class clean operations of delivery robots without contacts are required more and more. Magnetic levitation system can be applied to semiconductor fabrication applications, for example, which includes clamp-type robot, linear motors for propulsion, contact-less power supply for power sourcing and magnetic levitations for contact-less bearings. In this paper, electromagnetic suspension vehicle model and its decoupled control method is presented. The symmetry of the geometric configuration and space coordinates transformation techniques are used to eliminate the redundancy of electromagnetic force control. Then, each of the three motion states becomes a single-input and single-output (SISO) linear sub-system and a linear proportional, integral and derivative (PID) controller was designed for each sub-system and tested for the constructed electromagnetic suspension (EMS) vehicle simulator.
BibTeX:
@inproceedings{ISMB11_26,
  author = {Ki-Chang Lee and Ji-Woo Moon and Yeon-Ho Jeong and Dae-Wook Kang and Dae-Hyun Koo and Uhn-Joo Na and Seung-Heui Lee and Min-Cheol Lee},
  title = {Digital Control of Magnetic Levitation for Contactless Delivery Applications},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_26.pdf}
}
2008 Yamamoto, A., Kimura, M. and Hikihara, T. A Study on Indirect Suspension of Magnetic Target by Actively Controlled Permanent Magnet Proceedings of ISMB11  
Abstract: This paper discusses an indirect suspension of magnetic target through an actively controlled permanent magnet. This proposed system consists of an electromagnet, a permanent magnet and a target mainly. The dynamics of levitated bodies are restricted in one dimension, and the target issufficiently away from the electromagnet. The target is suspended by a proportional - derivative control with respect to the position and the velocity of the permanent magnet. The aim is to model the dynamics of levitated bodies by magnetic charges. The behav-iors of levitated bodies near the reference positions are studied numerically and experimentally. As a result, it is shown that the behaviors of levitated bodies near the reference positions can be described by the proposed model.
BibTeX:
@inproceedings{ISMB11_27,
  author = {Akihiro Yamamoto and Masayuki Kimura and Takashi Hikihara},
  title = {A Study on Indirect Suspension of Magnetic Target by Actively Controlled Permanent Magnet},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_27.pdf}
}
2008 Inoue, A., Fujioka, H., Morii, S. and Komori, M. Study on Shape Control and Vibration Absorber of Strip in Steel Process Line Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_28,
  author = {Atsushi Inoue and Hironori Fujioka and Shigeki Morii and Mochimitsu Komori},
  title = {Study on Shape Control and Vibration Absorber of Strip in Steel Process Line},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_28.pdf}
}
2008 Wamba, F.F. and Nordmann, R. Active Balancing of a Flexible Rotor in Active Magnetic Bearings Proceedings of ISMB11  
Abstract: Vibrations mostly caused by mass-unbalance reduce the reliability, the operational safety and the life cycle of high speed rotors. This leads to costly outages and un-scheduled maintenances. Commonly used offline bal-ancing processes are very expensive for the machine user. To reduce these costs and to realize an uninter-rupted control of the balancing states during operation, a complete automatic balancing strategy is proposed. It is based on the combination of the active magnetic bear-ings, the active balancing devices, and the drive motor and is applied to a flexible low pressure shaft of a heli-copter engine test rig. Experimental results validate the efficiency of the proposed strategy.
BibTeX:
@inproceedings{ISMB11_29,
  author = {Francis Fomi Wamba and Rainer Nordmann},
  title = {Active Balancing of a Flexible Rotor in Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_29.pdf}
}
2008 Mushi, S.E., Lin, Z., Allaire, P.E. and Evans, S. Aerodynamic Cross-Coupling in a Flexible Rotor on Magnetic Bearings: Control Design and Implementation Proceedings of ISMB11  
Abstract: This paper is concerned with modeling and active vibration control of a 1.23-m long ?exible shaft on active magnetic bearings that is designed to model a small industrial compressor and to serve as a platform for investigating emerging control schemes. Aerodynamic cross-coupled stiffness is one of the main contributors to rotordynamic instability in modern turbo-machines. The destabilizing effects of the cross-coupled stiffness are demonstrated. H2 and H8 synthesis approaches are used to design controllers that may stabilize the rotor-bearing system over a wide range of cross-coupled stiffness. Stability analysis and dynamic simulations of the resulting closed-loop systems are performed and recommendations made on the best means of achieving the desired performance and stability of the rotor-bearing system. The control and data-acquisition are in the process of being implemented in real-time using a DSP system.
BibTeX:
@inproceedings{ISMB11_3,
  author = {Simon E. Mushi and Zongli Lin and Paul E. Allaire and Stephen Evans},
  title = {Aerodynamic Cross-Coupling in a Flexible Rotor on Magnetic Bearings: Control Design and Implementation},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_3.pdf}
}
2008 Kato, T., Tsukada, S., Ishino, Y., Takasaki, M. and Mizuno, T. Electrostatic Suspension in 3-DOF by Using a Variable Capacitor Proceedings of ISMB11  
Abstract: A control system of electrostatic actuators using by variable capacitors has been proposed as one method of avoiding the use of high-speed and high-voltage amplifiers. This control system is applied to electrostatic suspension in this paper. An experimental apparatus is fabricated for demonstrating the feasibility of electrostatic suspension. The experimental results show 3-DOF electrostatic suspension is achieved with the proposed control system using variable capacitors.
BibTeX:
@inproceedings{ISMB11_30,
  author = {Takaaki Kato and Shinya Tsukada and Yuji Ishino and Masaya Takasaki and Takeshi Mizuno},
  title = {Electrostatic Suspension in 3-DOF by Using a Variable Capacitor},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_30.pdf}
}
2008 Maruyama, Y., Mizuno, T., Takasaki, M., Ishino, Y., Kameno, H. and Kubo, A. Application of Rotor Unbalance Compensation to AMB-Based Gyroscopic Sensor Proceedings of ISMB11  
Abstract: An AMB-based gyroscopic sensor is studied in this paper. The sensor has been proposed to realize high-accuracy, compact and low-cost sensors. In this sensor, active magnetic bearing (AMB) is applied to a rate-integrating gyro that measures angular velocity. Two-axis angular velocities are estimated from the control currents canceling gyroscopic torque acting on the AMB rotor. The sensor has detected angular velocity precisely. However, the measured angular velocities include oscillating components due to rotor unbalance. This paper presents an elimination method of the components due to the unbalance.
BibTeX:
@inproceedings{ISMB11_31,
  author = {Yutaka Maruyama and Takeshi Mizuno and Masaya Takasaki and Yuji Ishino and Hironori Kameno and Atsushi Kubo},
  title = {Application of Rotor Unbalance Compensation to AMB-Based Gyroscopic Sensor},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_31.pdf}
}
2008 Chen, H.M., Walter, T.J., Prisco, C.J., Chapman, P.A. and Donahue, A.C. Magnetically Levitated Blood Pump Using LCR Circuits Proceedings of ISMB11  
Abstract: An implantable blood pump has been developed for use as a left ventricular assist device (LVAD). The pump features total magnetic levitation of the shrouded centrifugal impeller. Sensorless levitation is achieved by using three ac magnets with tuned LCR circuits in the axial direction and a pair of permanent magnet rings in the radial direction. This paper describes design issues related to the pump’s magnetic levitation system; pump impact on patient physiology is not addressed.
BibTeX:
@inproceedings{ISMB11_32,
  author = {H. Ming Chen and Thomas J. Walter and Charles J. Prisco and Peter A. Chapman and Arthur C. Donahue},
  title = {Magnetically Levitated Blood Pump Using LCR Circuits},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_32.pdf}
}
2008 Kurita, N., Timms, D.L., Greatrex, N. and Masuzawa, T. Axial Magnetic Bearing Development for the BiVACOR rotary BiVAD/TAH Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_33,
  author = {Nobuyuki Kurita and Daniel Lee Timms and Nick Greatrex and Toru Masuzawa},
  title = {Axial Magnetic Bearing Development for the BiVACOR rotary BiVAD/TAH},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_33.pdf}
}
2008 da Costa, E.A., Chabu, I.E. and da Cruz, J.J. Application of Active Magnetic Bearing for Tubular Linear Induction Motor in Oil Pumping Proceedings of ISMB11  
Abstract: An active magnetic bearing (AMB) to support the shaft of a tubular linear induction motor (TLIM) applied to oil pumping is proposed. Instead of the usual eight-pole AMB, a different concept is adopted where a DC-excited primitive bearingless machine is used as a magnetic bearing. The AMB is a 3-phase one for which a lower number of wires connections and power devices are among its advantages. This paper focuses on the design of the AMB system. A finite element analysis of the flux density and of the relationship between the radial force and the suspension winding current are explored. The magnetic system is modeled and simulation is performed to tune the controller parameters.
BibTeX:
@inproceedings{ISMB11_34,
  author = {Eduardo Alves da Costa and Ivan Eduardo Chabu and Jose Jaime da Cruz},
  title = {Application of Active Magnetic Bearing for Tubular Linear Induction Motor in Oil Pumping},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_34.pdf}
}
2008 Nonami, K., Rachmanto, B., Kuriyama, K., Sato, Y., Kondo, K., Kubo, A. and Takahata, R. AMB Flywheel-Powered Electric Vehicle Proceedings of ISMB11  
Abstract: This paper describes the new cocept and the configuration of AMB Flywheel-powered Electric Vehicle (AMB-FPEV) as the overview paper. In particular,flywheel (FW) energy storage system of AMB system, gimbal system, electric power steering system, circuit system of energy charge and discharge system, and partially autonomous driving control system are described. The real experimental data at outdoor running on the street is also shown with low speed.
BibTeX:
@inproceedings{ISMB11_35,
  author = {Kenzo Nonami and Budi Rachmanto and Kenta Kuriyama and Yukihiko Sato and Keiichiro Kondo and Atsushi Kubo and Ryoichi Takahata},
  title = {AMB Flywheel-Powered Electric Vehicle},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_35.pdf}
}
2008 Yoo, S.-Y., hoon Park, C., kyu Choi, S. and Noh, M.D. Flexible Rotor Modeling for a Large Capacity Flywheel Energy Storage System Proceedings of ISMB11  
Abstract: When we design a controller for the active magnetic bearings that support a large rotor, it is important to have an accurate model of the rotor. For the case of the flywheel that is used to store energy, an accurate rotor model is especially important because the dynamics change with respect to the running speed due to gyroscopic effects. In this paper, we present a procedure of obtaining an accurate rotor model of a large flywheel energy storage system using finite-element method. The system is designed to store 5kWh at maximum speed of 18,000 rpm. The model can predict the first and the second bending mode which match well with the experimental results obtained from a prototype flywheel energy storage system.
BibTeX:
@inproceedings{ISMB11_36,
  author = {Seong-Yeol Yoo and Cheol-hoon Park and Sang-kyu Choi and Myounggyu D. Noh},
  title = {Flexible Rotor Modeling for a Large Capacity Flywheel Energy Storage System},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_36.pdf}
}
2008 Rachmanto, B., Nonami, K. and Kuriyama, K. Attitude Control of Flywheel with Two-Axis Gimbal and Nonlinear Input Shaping Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_37,
  author = {Budi Rachmanto and Kenzo Nonami and Kenta Kuriyama},
  title = {Attitude Control of Flywheel with Two-Axis Gimbal and Nonlinear Input Shaping},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_37.pdf}
}
2008 Xiao, K., Liu, K. and Chen, X. Cross Feedback Control of Hybrid Magnetic Bearings Based on Root Locus Proceedings of ISMB11  
Abstract: The design and analysis method on cross feedback controller is presented for the flat outer-rotor flywheel. Two sets of characteristic equations of rotation are discussed on different bearing condition. Stability analysis is discussed by the comparison between conventional PD controller and controller with cross feedback. And in the end, relationship between controller’s parameters and motion of nutation and precession is investigated by means of root locus analysis. The strong gyroscopic effects are overcome in the after experiments by the implementing of cross feedback control.
BibTeX:
@inproceedings{ISMB11_38,
  author = {Kai Xiao and Kun Liu and Xiaofei Chen},
  title = {Cross Feedback Control of Hybrid Magnetic Bearings Based on Root Locus},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_38.pdf}
}
2008 Kimman, M., Langen, H., Schmidt, R.M., Borislavljevic, A. and Polinder, H. Design and Realization of a Miniature Milling Spindle with Active Magnetic Bearings Proceedings of ISMB11  
Abstract: This paper describes the design of two active magnetic bearing spindle systems. A miniature active magnetic bearing spindle, with two radial bearings, one axial bearing and a permanent magnet synchronous motor has been built. The spindle is controlled by five, decentralized PID controllers. The closed loop bandwidth of the system is 380 Hz. The static positioning error was measured to be below 45 nm (1sigma). This spindle has been tested with rotational speeds up to 120.000 rpm. To reach higher rotational speeds a second miniature active magnetic bearing spindle has been designed. The rotor dimensions are smaller than in the first generation in both length and diameter. The basic design concept is a small disk shaped rotor, which eliminates the passing of one rigid mode and several flexible body modes during startup. The gyroscopic coupling in a disk shaped rotor is larger when a relatively short rotor is applied. In this research, the aim is to use resistance of a gyroscope against tilting to an advantage.
BibTeX:
@inproceedings{ISMB11_39,
  author = {Maarten Kimman and Hans Langen and Rob Munnig Schmidt and Aleksandar Borislavljevic and Henk Polinder},
  title = {Design and Realization of a Miniature Milling Spindle with Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_39.pdf}
}
2008 Okada, Y., Sagawa, K., Suzuki, E. and Kondo, R. Development and Application of Parallel PM Type Hybrid Magnetic Bearings Proceedings of ISMB11  
Abstract: Hybrid magnetic bearing is recognized as an e?cient one even with wide airgap and suitable for low loss and wide gap application. Previously sub-pole type IPM hybrid magnetic bearing has been proposed. However the sub-pole produces bias ?ux and cannot produce any control force. To overcome this problem, two new types of hybrid magnetic bearings are proposed which have permanent magnets within their stator cores. This paper introduces structure and principle of the proposed magnetic bearings. The geometric parameters of these new type magnetic bearings are optimized using FEM analysis. The experimental setups are made based on these analytical results. The fundamental characteristics are measured and compared with the estimated bearing performances. The results show stable levitation and good levitated rotation.
BibTeX:
@inproceedings{ISMB11_4,
  author = {Yohji Okada and Kouji Sagawa and Eisaku Suzuki and Ryou Kondo},
  title = {Development and Application of Parallel PM Type Hybrid Magnetic Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_4.pdf}
}
2008 Zhang, X., Shinshi, T., Morita, H., Shimokohbe, A., Sato, T., Miyake, H. and Nakagawa, T. A maglev Local Actuator for High Speed Electrical Discharge Machining Proceedings of ISMB11  
Abstract: This paper reports on a compact, 5-degrees-of-freedom (5-DOF) controlled maglev local actuator (MLA) for realizing high speed electrical discharge machining (EDM), comprising a magnetic coupling mechanism (MCM) to feed a discharge current to an electrode attached to a spindle, and to transmit a torque from a motor to the spindle. The spindle is supported by a 5-DOF controlled magnetic bearing and is rotated by following the rotation of a power supply ring, utilizing the magnetic coupling. Flexible wires between the power supply ring and the spindle feed the discharge current to the electrode, without transmitting disturbing forces, so that the spindle is free from the direct contact with brushes, used to feed the discharge current. Experimental positioning results show a prototype MLA possesses a positioning resolution of a few microns and several ten micro-radians, bandwidths greater than 100 Hz in the 5-DOF directions, and a positioning stroke of 2mm in the thrust direction. Moreover, the discharge current can be fed to the electrode attached to the spindle, rotating at 2,000min.
BibTeX:
@inproceedings{ISMB11_40,
  author = {Xiaoyou Zhang and Tadahiko Shinshi and Hiroki Morita and Akira Shimokohbe and Tatsushi Sato and Hidetaka Miyake and Takayuki Nakagawa},
  title = {A maglev Local Actuator for High Speed Electrical Discharge Machining},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_40.pdf}
}
2008 Schulz, A., Gross, B., Neumann, M. and Wassermann, J. A sophisticated active magnetic bearing system with supreme reliability Proceedings of ISMB11  
Abstract: Within this work a new active magnetic bearing (AMB)-system offering supreme reliability is presented. It provides bearing capacity even in case of a defect within any sub-assembly over the whole operating time. Each AMB consists of completely decoupled electro-magnet (EM)-channels configured in hot redundancy, comprising a singular EM, controlled and driven by a decentralized hot-swap controller amplifier module (HCA) and one displacement sensor. Each HCA is responsible for controlling the position of the structure towards its dedicated EM and comprises a digital controller, a switching amplifier, local power supplies, and a local error detection unit. All functional EM-channels contribute to support the structure. On occurrence of an error within a certain EM-channel this error is detected by the local error detection unit and the defective EM-channel auto-matically shuts down. The adjacent redundant EM-channels take over the bearing functionality and the defective sub-assembly can be replaced during system operation (hot-swap) without degrading system performance. This paper gives detailed information on the AMB functionality and the HCA design.
BibTeX:
@inproceedings{ISMB11_41,
  author = {Alexander Schulz and Berhard Gross and Manfred Neumann and Johann Wassermann},
  title = {A sophisticated active magnetic bearing system with supreme reliability},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_41.pdf}
}
2008 Shinshi, T., Goto, S., Zhang, X., Shimokohbe, A. and Takatani, S. A Mini-Centrifugal Blood Pump Using 2-DOF Controlled Magnetic Bearing Proceedings of ISMB11  
Abstract: A mini-centrifugal blood pump (CBP) employing a two-degrees-of-freedom (2-DOF) controlled MB has been developed as a ventricular assist device. In this pump, a magnetically suspended impeller is driven by an internal brushless DC motor. The developed maglev CBP (55 mm in diameter, 25 mm in height, 59 ml in total volume and 16 ml in priming volume) is more compact than conventional maglev CBPs (cf. one third of the total volume of ‘DuraHeart’) and it offers the necessary pump performance to provide implantable cardiac assistance to adults.
BibTeX:
@inproceedings{ISMB11_42,
  author = {Tadahiko Shinshi and Shunji Goto and Xiaoyou Zhang and Akira Shimokohbe and Setsuo Takatani},
  title = {A Mini-Centrifugal Blood Pump Using 2-DOF Controlled Magnetic Bearing},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_42.pdf}
}
2008 Elder, N. and Maslen, E. Effect of Long Cables on AMB Systems Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_43,
  author = {Nicholas Elder and Eric Maslen},
  title = {Effect of Long Cables on AMB Systems},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_43.pdf}
}
2008 Park, S.-H. and Lee, C.-W. Decoupled Control Using Redundant Coordinates for Three-pole Hybrid Active Magnetic Bearing System Proceedings of ISMB11  
Abstract: In this paper, we propose a bearing redundant coordinates and decoupled PD controller for 5-axis active magnetic bearing system, which consists of two bearing parts such as three-pole hybrid active magnetic bearing to stabilize the radial direction and ring-type permanent magnetic bearing stabilizing in axial and tilting motion. Based on derived system equation with decoupled control scheme, we examine controllability and observability as well as numerical modal analysis. The experiments are also carried out in order to verify the effectiveness of the proposed controller in stabilizing the transient and steady state response of the rotor.
BibTeX:
@inproceedings{ISMB11_44,
  author = {Sang-Hyun Park and Chong-Won Lee},
  title = {Decoupled Control Using Redundant Coordinates for Three-pole Hybrid Active Magnetic Bearing System},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_44.pdf}
}
2008 Abulrub, A.-H.G., Sahinkaya, M.N., Burrows, C.R. and Keogh, P.S. Robustness of Recursive Auto-Tuning Strategy in Flexible Rotor and Magnetic Bearing Systems Proceedings of ISMB11  
Abstract: Active magnetic bearings offer the capability to control rotor vibration and transmitted forces through the design of adaptive controllers. These controllers can take into account the changing operating conditions and variations in the system dynamics. A Recursive Open-Loop Adaptive Control (ROLAC) algorithm was developed, which minimizes the sum of squares of the measurements in frequency domain. ROLAC is used in addition to local PID controllers, which ensure the stability. Magnetic bearing dynamics depend on the eccentricity of the rotor with respect to magnetic poles. Non-concentric rotation of the rotor within the magnetic bearings causes changes in the bearing dynamic properties. Apart from system faults, non-concentric operation of the rotor can occur due to misalignment of the auxiliary bearings with respect to magnetic poles, changes in sensor calibration, and misalignment of bearings in systems where there are three or more bearings. This misalignment leads to changes in the magnetic bearing characteristics thereby affecting the overall system dynamics. This in turn may necessitate re-tuning of the ROLAC. The paper studies the effect of such misalignments on the controller performance and the robustness of the auto-tuning process.
BibTeX:
@inproceedings{ISMB11_45,
  author = {Abdul-Hadi G Abulrub and M Necip Sahinkaya and Clifford R Burrows and Patrick S Keogh},
  title = {Robustness of Recursive Auto-Tuning Strategy in Flexible Rotor and Magnetic Bearing Systems},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_45.pdf}
}
2008 Zheng, K., Sun, Y. and Yu, L. Robust Fuzzy Control of an Active Magnetic Bearing with Delayed Feedback Proceedings of ISMB11  
Abstract: This paper presented a robust fuzzy logic-base control scheme for a nonlinear magnetic bearing system with delayed feedback. A proper Takagi-Sugeno fuzzy model was chosen to represent the nonlinear magnetic bearing. A fuzzy-model-based PDC controller was designed in terms of a proposed delay-dependent stability criterion which guarantees the asymptotic stability of the fuzzy model. The results of simulation verified the effectiveness and superiority of the proposed method.
BibTeX:
@inproceedings{ISMB11_46,
  author = {Kai Zheng and Yanhua Sun and Lie Yu},
  title = {Robust Fuzzy Control of an Active Magnetic Bearing with Delayed Feedback},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_46.pdf}
}
2008 Eirich, M., Ishino, Y., Takasaki, M. and Mizuno, T. Experimental Study on the Adjustability of Radial Stiffness in a Repulsive Magnetic Bearing Device Proceedings of ISMB11  
Abstract: This paper studies the ability to adjust the stiffness in the radial direction on a non-contact levitated rotor by using an independent motion control of permanent magnets. The method of stabilization in the axial direction, by moving a magnet for support like an inverted pendulum, is applied. The repulsive forces in the radial direction depend not only on the size and physical characteristics of magnets but also on the relative positioning of magnets to each other in the axial direction. This work shows the principles and the one of necessary methods of motion control for successful adjustability of the radial stiffness.
BibTeX:
@inproceedings{ISMB11_47,
  author = {Max Eirich and Yuji Ishino and Masaya Takasaki and Takeshi Mizuno},
  title = {Experimental Study on the Adjustability of Radial Stiffness in a Repulsive Magnetic Bearing Device},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_47.pdf}
}
2008 Lee, J.H. A Controller Design to Suppress the Interference Force of the Propulsion Equipment Acting on the Suspension System in a Magnetically Levitated Train System Proceedings of ISMB11  
Abstract: In this paper we deal with a design of integral sliding mode controller to reject the disturbance force acting on the suspension system in a magnetically levitated system which is propelled by the linear induction motor. The control scheme consists of an integral compensator which is designed to achieve zero steady-state error under step disturbances, and a sliding mode controller which is designed for enhancing robustness under plant uncertainties. A proper continuous design signal is introduced to overcome the chattering problem. The disturbance force produced by the linear induction motor is formularized by using a curve fitting method. Computer simulations show the effectiveness of the designed integral sliding mode controller to reject the disturbance force in comparison with a simple sliding mode controller that does not include the integral compensator.
BibTeX:
@inproceedings{ISMB11_48,
  author = {Jun Ho Lee},
  title = {A Controller Design to Suppress the Interference Force of the Propulsion Equipment Acting on the Suspension System in a Magnetically Levitated Train System},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_48.pdf}
}
2008 Paulides, J.J.H., Janssen, J.L.G. and Lomonova, E. Passive Attraction Force Reduction for Linear Permanent Magnet Actuators Proceedings of ISMB11  
Abstract: With the ever advancement and increased force density of slotted brushless linear permanent magnet (PM) actuators the attraction forces become more dominating. Where in the early years this attraction force was advantageous it now becomes a problem due to reduced bearing lifetime.
BibTeX:
@inproceedings{ISMB11_49,
  author = {J. J. H. Paulides and J. L. G. Janssen and E. Lomonova},
  title = {Passive Attraction Force Reduction for Linear Permanent Magnet Actuators},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_49.pdf}
}
2008 Xie, Z., Xu, L., Gao, H., Zhang, J. and Huang, P. Dynamic Characteristics of the Magnetic Bearing System with Magnetic Damper Proceedings of ISMB11  
Abstract: The magnetic damper is introduced into the ordinary magnetic bearing system. Dynamic characteristics of the magnetic bearing system with the magnetic damper are investigated by the theoretical calculation, the experimental modal analysis, and the actual operation of the system, respectively. Compared with the ordinary magnetic bearing system, the modal damps on the 1st and 2nd bending critical speeds have increased a lot, the vibration of the rotor has been reduced, and the system can get across the first two bending critical speeds, and operate on 16,800 rotations per minute safely.
BibTeX:
@inproceedings{ISMB11_5,
  author = {Zhenyu Xie and Longxiang Xu and Hua Gao and Jingting Zhang and Peizhen Huang},
  title = {Dynamic Characteristics of the Magnetic Bearing System with Magnetic Damper },
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_5.pdf}
}
2008 Wu, Q., Zhu, H., Zhu, D. and Shen, Y. Configuration Design and 3D-FEM Analysis for a Radial-Axial Hybrid Magnetic Bearing Proceedings of ISMB11  
Abstract: In this paper, an innovated radial-axial hybrid magnetic bearing (HMB) is proposed, which is driven by a 2-phase AC power inverter in radial directions and a DC amplifier in axial direction respectively. The axial and radial biased magnetic fluxes of this magnetic bearing are provided by a common radial polarized permanent magnet ring, and the axial and radial control magnetic fluxes are provided by the inner and outer two-layer coils, respectively. The configuration and the principle producing magnetic suspension forces of the radial-axial HMB are introduced. The flux path is calculated by using the method of equivalent magnetic circuit, the mathematics models of the axial and radial magnetic suspension forces are deduced. The experiment prototype of the innovated bearing is designed and the practical prototype’s parameters are given. The feasibility and the correctness of the theoretical methods for the configuration, magnetic path and maximum loads capacity of the radial-axial HMB are verified by using a 3D-FEM software (Maxwell 3D of ANSOFT). The theoretical approach and finite element simulated experiment have shown that the mechanical structure and magnetic circuit of this magnetic bearing are legitimacy. The radial control flux and the axial control flux are independent, the magnetic paths between radial direction and axial direction have no coupling. This radial-axial HMB can be applied in high speed machine tool spindle with lower manufacturing and operation costs.
BibTeX:
@inproceedings{ISMB11_50,
  author = {Qinghai Wu and Huangqiu Zhu and Dehong Zhu and Yuxiang Shen},
  title = {Configuration Design and 3D-FEM Analysis for a Radial-Axial Hybrid Magnetic Bearing},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_50.pdf}
}
2008 Barrot, F. and Bleuler, H. Application of Diamagnetic Levitation to Mechatronic Systems Proceedings of ISMB11  
Abstract: Diamagnetic levitation is the only passive levitation technique working at room temperature. Using planar arrangements of permanent magnets, it is indeed possible to levitate diamagnetic materials at room temperature. Such a principle is particularly interesting to use for the design of mechatronic systems, especially in applications where friction between mechanical parts should be avoided such as, for instance, high precision inertial sensors or actuators for clean-room applications. In this article the authors show with some examples extracted from their research on the subject, that diamagnetic levitation is a promising technique that can be of great interest for the design of small scale mechatronic systems.
BibTeX:
@inproceedings{ISMB11_51,
  author = {Francois Barrot and Hannes Bleuler},
  title = {Application of Diamagnetic Levitation to Mechatronic Systems},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_51.pdf}
}
2008 Suzuki, H., Itatsu, K., Saito, R., Kanke, M. and Ito, A. Design of Novel Contact-Free Disk Suspension and Rotation System Utilizing Diamagnetic Graphite Proceedings of ISMB11  
Abstract: The energy-saving actuation system is a valuable element in various industry fields using micro mechatronics technology. In the recent five years, we have produced some kinds of proto-model of novel contact-free disk suspension and linear motion devices by using diamagnetic graphite (Pyrolytic Graphite: PG) plate. Especially, a contact-free linear drive by using PG plates and small piece magnets is very useful as an extremely energy saving actuation technique. Very recently, we got a unique result as a successive acceleration motion of PG plate on Halbach PM array. We are getting ready to confirm it by using ring Halbach PM array.
BibTeX:
@inproceedings{ISMB11_52,
  author = {Haruhiko Suzuki and Kazuto Itatsu and Ryosuke Saito and Minoru Kanke and Atsushi Ito},
  title = {Design of Novel Contact-Free Disk Suspension and Rotation System Utilizing Diamagnetic Graphite},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_52.pdf}
}
2008 Mitsuda, H., Subkhan, M., Inoue, A. and Komori, M. Energy Storage Flywheel System with SMB and PMB and Its Performances Proceedings of ISMB11  
Abstract: Since few years ago, electrical energy storage had attracted attention as an effective use of electricity and coping with the momentary voltage drop. Above all, the flywheel energy storages using superconductor have the advantages of long life, high energy density, and high efficiency. Our experimental machine uses the superconducting magnetic bearing (SMB) together with the permanent magnetic bearing (PMB) and plans to reduce the overall cost using the superconductor cost, and cooling cost. The purpose in this paper is to show the progress in the system performance by the improvement of PMB and the motor drive, and to estimate the system at that time of momentary voltage drop by making the discharge system.
BibTeX:
@inproceedings{ISMB11_53,
  author = {Hisashi Mitsuda and Mukhamad Subkhan and Atsushi Inoue and Mochimitsu Komori},
  title = {Energy Storage Flywheel System with SMB and PMB and Its Performances},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_53.pdf}
}
2008 Sandtner, J. and Bleuler, H. Compact Passive Electrodynamic Thrust Bearing- Electrodynamic Bearings- Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_54,
  author = {Jan Sandtner and Hannes Bleuler},
  title = {Compact Passive Electrodynamic Thrust Bearing- Electrodynamic Bearings-},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_54.pdf}
}
2008 Zhu, H., Cheng, Q., Wu, Q. and Pan, W. Radial Force Control of Bearingless Motor with Flux Equivalent Air-Gap Virtual Winding Current Proceedings of ISMB11  
Abstract: A bearingless motor has two kinds of coupling windings, driving windings and bearing windings. The decoupling control for two sets of winding currents is difficult problem and key technology to stable operation of bearingless motors. A simple, reliable and accurate analyzing method for bearingless motors is put forward using the concept of flux equivalent air-gap virtual winding currents. Adopting this method, the operation condition PB=PM±1 for bearingless motor is quoted, and the necessary satisfied condition of generating a stable radial force in single direction on whole rotor’s circumference is derived. On this basis, the control strategy of realizing bearingless motor’s suspension operation is brought forward, and a prototype of bearingless surface-mounted permanent magnet synchronous motor is built and tested. The experiment results have shown that theory analysis of this strategy is accurate, a stable and reliable radial suspension force is obtained, and the validity and feasibility of this strategy is confirmed.
BibTeX:
@inproceedings{ISMB11_55,
  author = {Huangqiu Zhu and Qiuliang Cheng and Qinghai Wu and Wei Pan},
  title = {Radial Force Control of Bearingless Motor with Flux Equivalent Air-Gap Virtual Winding Current},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_55.pdf}
}
2008 Gruber, W., Amrhein, W. and Stallinger, T. Bearingless Segment Motor with Buried Magnets Proceedings of ISMB11  
Abstract: Bearingless motors combine contactless levitation and rotation in a preferably compact system design, because the bearing as well as motor windings are located on the same lamination stack. By the use of a proper control scheme and the superposition of different current components, bearing forces and motor torque can be generated simultaneously by applying concentrated windings. This leads to a further simplification of the mechanical configuration. The bearingless segment motor features such concentrated coils on separated stator elements, which reduce the stator iron and therefore weight and cost, especially for constructions with large diameters. However, most of the bearingless motors are de-signed with surface mounted permanent magnets on the rotor, neglecting the advantages of buried permanent magnets. In this paper a bearingless segment motor with buried permanent magnets is investigated. The mathematical model is presented, a proper control scheme is introduced and the optimization of the prototype motor is outlined. Some motor specific considerations concerning the angular sensors and the rotordynamic are also given. Finally, the performance of the bearingless segment motor with buried permanent magnets is shown by the comparison of simulation results with measurement data of the manufactured prototype.
BibTeX:
@inproceedings{ISMB11_56,
  author = {Wolfgang Gruber and Wolfgang Amrhein and Thomas Stallinger},
  title = {Bearingless Segment Motor with Buried Magnets},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_56.pdf}
}
2008 Wang, H., Lee, D.-H. and Ahn, J.-W. Calculation of Suspending Force for New Bearingless Switched Reluctance Motor Proceedings of ISMB11  
Abstract: In order to decouple the rotational torque and suspending radial force from stator winding, a novel bearingless switched reluctance motor (BLSRM) with hybrid stator poles structure is proposed in this paper. The proposed BLSRM has wide stator poles in rectangular axis. And other stator poles generate torque. So, it can be controlled the air-gap more easily with decoupled suspending radial force. The simple structure can reduce the number of power devices. A prototype design is analyzed by the finite element method (FEM) and mathematic model to evaluate the performances. The validity of structure and mathematic model is verified by simulation results.
BibTeX:
@inproceedings{ISMB11_57,
  author = {Huijun Wang and Dong-Hee Lee and Jin-Woo Ahn},
  title = {Calculation of Suspending Force for New Bearingless Switched Reluctance Motor},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_57.pdf}
}
2008 Amada, M., Miyamoto, N., Enomoto, T., Tanabe, N., Asama, J., Chiba, A., Fukao, T., Iwasaki, S. and Takemoto, M. Inverter Voltage and Suspension Characteristics of a Bearingless Motor Proceedings of ISMB11  
Abstract: A wide magnetic gap consequent-pole type bearingless motor has been developed. The wide magnetic gap makes it difficult to start up and suspend a shaft with reasonable suspension voltage and current. To provide high current, high voltage rating is demanded, although, high voltage causes bad influence on magnetic suspension. In this paper, the authors investigate the start-up and rotational characteristics of a prototype bearingless machine driven by voltage source inverters having the rated voltage of 200V and 100V. When the rated voltage is not suitable, significant problems are occurred. The effectiveness of proper selection in the rated voltage is discussed.
BibTeX:
@inproceedings{ISMB11_58,
  author = {Miya Amada and Naoya Miyamoto and Takehiro Enomoto and Norimasa Tanabe and Junichi Asama and Akira Chiba and Tadashi Fukao and Satoru Iwasaki and Masatsugu Takemoto},
  title = {Inverter Voltage and Suspension Characteristics of a Bearingless Motor},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_58.pdf}
}
2008 Swann, M.K., Tsunoda, E. and Sarichev, A.P. A Diffusion Model for Active Magnetic Bearings in Large Turbomachinery Proceedings of ISMB11  
Abstract: The interest in AMB technology spans over two decades of application to large turbomachinery yet there is not a suitable mathematical model used in this industry that describes the penetration of the technology into the domain of conventional oil lubricated bearings. This paper adapts previous work in product diffusion models to this purpose.
BibTeX:
@inproceedings{ISMB11_59,
  author = {Michael K. Swann and Eiji Tsunoda and Aleksey P. Sarichev},
  title = {A Diffusion Model for Active Magnetic Bearings in Large Turbomachinery},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_59.pdf}
}
2008 Arredondo, I. and Jugo, J. Frequency Noise Rejection for Vibration Minimization in an AMB System Proceedings of ISMB11  
Abstract: When a vibration suppression adaptive algorithm is implemented to enhance an AMB based system, a good frequency measurement or estimation of the synchronous rotation is essential [1]. In this paper, two frequency disturbance rejection methods applied to the frequency sensor measurement are compared. The ?rst method is based on the use of a Kalman Filter (KF) and the second is the implementation of a Frequency Locked Loop (FLL). Both have advantages and disadvantages related to the available hardware, noise type of the sensor, the fact of vibration minimization and the computational cost of the adaptive algorithm. Finally, experimental proofs in a laboratory testbed, based on the MBC500 Rotor Dynamics, show the effectiveness of each method.
BibTeX:
@inproceedings{ISMB11_6,
  author = {Inigo Arredondo and Josu Jugo},
  title = {Frequency Noise Rejection for Vibration Minimization in an AMB System},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_6.pdf}
}
2008 Worlitz, F. and Rottenbach, T. Long-term Operation of an AMB-Supported Coolant Pump in a Lignite Fired Power Station -Results and Operational Experiences- Proceedings of ISMB11  
Abstract: A conventionally suspended coolant pump was converted to a pump with complete active magnetic bearings and installed in a lignite power plant for demonstrating purposes. The main objectives were to test the possibilities of active magnetic bearings in turbo machines operating in a power plant and to proof their suitability. After commissioning the pump was used and tested in the power plant regime for this purpose. In addition, using the system-inherent signals of the magnetic bearings allows a machine and facility diagnosis and an online determination of the bearing forces.
BibTeX:
@inproceedings{ISMB11_60,
  author = {Frank Worlitz and Torsten Rottenbach},
  title = {Long-term Operation of an AMB-Supported Coolant Pump in a Lignite Fired Power Station -Results and Operational Experiences-},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_60.pdf}
}
2008 Inoue, A., Fujioka, H., Morii, S. and Komori, M. Study on Stability of Steel Strip under the Electromagnetic Shape Controller Proceedings of ISMB11  
Abstract: In a steel process line, shape controllers of steel strip using electromagnets are important devices for improving strip quality and line speed. It is confirmed that the devices are beneficial when these are applied to Continuous Galvanizing Line (CGL). However, it is necessary to avoid a static instability phenomenon by negative spring of the electromagnet, and a spill-over phenomenon by the high gain of the control system in this device. We proposed an analysis model combining the control system with the steel strip. The model was applied to a real machine to confirm the availabilities. Moreover, this paper discusses the static instability phenomenon and the spill-over phenomenon.
BibTeX:
@inproceedings{ISMB11_61,
  author = {Atsushi Inoue and Hironori Fujioka and Shigeki Morii and Mochimitsu Komori},
  title = {Study on Stability of Steel Strip under the Electromagnetic Shape Controller},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_61.pdf}
}
2008 Liu, S., Bian, Z., Yu, W. and Maslen, E. The Application of Active Magnetic Bearing Spindle in High-Speed and High-Precise Grinding Machine Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_62,
  author = {Shuqin Liu and Zhongguo Bian and Wentao Yu and Eric Maslen},
  title = {The Application of Active Magnetic Bearing Spindle in High-Speed and High-Precise Grinding Machine},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_62.pdf}
}
2008 Xie, L., Nordmann, R. and Aeschlimann, B. Numerical Investigation of AMB Supported Rotor Interaction with Auxiliary Bearing Proceedings of ISMB11  
Abstract: This paper describes numerical analysis of interaction between rotor and auxiliary bearing due to high transient overloads. When the fast spinning rotor interacts with the auxiliary bearing that does not move, some critical states of motion are possible. One of these motions, backward whirl, reaches very high frequencies and thus can produce very high loads on rotor and bearings, which can lead to the destruction of the machine. The detailed model of the AMB supported rotor auxiliary bearing system considers discontinuous stiffness caused by bearing clearance effects, auxiliary bearing fixed or flexible mount types, nonlinear Hertzian contact stiffness and Coulomb friction forces. Numerical investigations as time history, orbit diagram, bifurcation diagram, Poincaré section diagram are proposed to study the system parameters which extremely influence the whole dynamic response. One of the important parameters, rotor driving frequency, can be modelled as time variable parameter in the detailed system model. Moreover, parameters used in the detailed model discussed in this paper obtained from experimental test rig.
BibTeX:
@inproceedings{ISMB11_63,
  author = {Lei Xie and Rainer Nordmann and Beat Aeschlimann},
  title = {Numerical Investigation of AMB Supported Rotor Interaction with Auxiliary Bearing},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_63.pdf}
}
2008 Ginzinger, L. and Ulbrich, H. Simulation-Based Controller Design for an Active Auxiliary Bearing Proceedings of ISMB11  
Abstract: A framework for the development of a feedback controller for an active auxiliary bearing is presented. Experiments show the success the developed control concept. A simulation for the elastic rotor and the auxiliary bearing including the non-smooth nonlinear dynamics of the rubbing contact is used to de-velop the feedback controller. The auxiliary bearing is attached to the foundation via two unidirectional actuators. The control force is applied indirectly using the active auxiliary bearing only in case of rubbing. Experimental studies have been carried out at a rotor test rig. The experiments show the outstanding success of the strategy. In case of rubbing, the contact forces are reduced up to 85%.
BibTeX:
@inproceedings{ISMB11_64,
  author = {Lucas Ginzinger and Heinz Ulbrich},
  title = {Simulation-Based Controller Design for an Active Auxiliary Bearing},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_64.pdf}
}
2008 Yoon, S.Y., Lin, Z., Lim, K.T. and Allaire, P.E. Compressor Surge Control with AMB Actuation Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_65,
  author = {Se Young Yoon and Zongli Lin and Kin Tien Lim and Paul E Allaire},
  title = {Compressor Surge Control with AMB Actuation},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_65.pdf}
}
2008 Zhou, D. and Zhu, C. A Novel Hysteresis Current Control Strategy for Switching Power Amplifiers in Active Magnetic Bearings Proceedings of ISMB11  
Abstract: A switching power amplifier with hysteresis current control strategy in active magnetic bearings has the characters of a simple implementation, a high dynamic response and a good performance on small signal sensitivity. However, for the frequency limit of switch element, the hysteresis band can’t be too small. In this paper, a novel double band hysteresis current control strategy is proposed, where an additional hysteresis band is brought in the conventional hysteresis band current control strategy. The proposed method can realize tri-state modulation, and reduce the switching frequency at the same hysteresis band. Theoretical analysis, simulations and experiments have verified that the switching power amplifier with double band hysteresis current control strategy has lower switching frequency and smaller current error.
BibTeX:
@inproceedings{ISMB11_66,
  author = {Dan Zhou and Changsheng Zhu},
  title = {A Novel Hysteresis Current Control Strategy for Switching Power Amplifiers in Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_66.pdf}
}
2008 Jastrzebski, R.P. and Pöllänen, R. Trade Offs in LQ/LTR Control Designs for MIMO AMB Systems Proceedings of ISMB11  
Abstract: This study evaluates the design tradeoffs of linear-quadratic (LQ) and LQ / loop transfer recovery (LTR) controllers for MIMO AMB system. The comparison of the LQ regulator with the Kalman filter, LQ/LTR design, and classical PID and PI/PD cascaded controllers is presented. The properties of the tested control configurations are examined using maximum singular values of the output sensitivity function of the close-loop system and the tolerated disturbance force at the input of the plant. Furthermore, the indexes such as measured peak output sensitivity, responses to the step reference position and step disturbance are examined. The simulation and experimental results from the test-rig are compared.
BibTeX:
@inproceedings{ISMB11_67,
  author = {Rafal Piotr Jastrzebski and Riku Pöllänen},
  title = {Trade Offs in LQ/LTR Control Designs for MIMO AMB Systems},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_67.pdf}
}
2008 Dietz, S.G., Balini, N.K.H. and Scherer, C.W. Robust Control Against Disturbance Model Uncertainty in Active Magnetic Bearings Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_68,
  author = {Sjoerd G. Dietz and Navin Kumar H.M. Balini and Carsten W. Scherer},
  title = {Robust Control Against Disturbance Model Uncertainty in Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_68.pdf}
}
2008 Jastrzebski, R.P. and Pöllänen, R. Observer-Based Unbalance Compensation in LQ-Control of AMBs Proceedings of ISMB11  
Abstract: In this work, a model-based linear-quadratic controller with an optimal observer-based unbalance force rejection control for variable speed magnetically suspended rotors is presented. The unbalance force rejection control is considered in two variants. In the first one, the unbalance forces are canceled and the system can maintain an accurate reference rotor position. This variant results in low measured vibration amplitudes. In the second one, the magnetic force vibrations are canceled and the rotor spins about its principal axis of inertia within the bearing clearance. The control currents and energy usage are minimal, and the vibrations are slightly decreased. Both cases are designed as a periodic disturbance observer. Simulations for the variable speed and an experimental evaluation at the constant speed are presented.
BibTeX:
@inproceedings{ISMB11_69,
  author = {Rafal Piotr Jastrzebski and Riku Pöllänen},
  title = {Observer-Based Unbalance Compensation in LQ-Control of AMBs},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_69.pdf}
}
2008 Jugo, J. and Arredondo, I. Adaptive Control for Attenuating Vibrations in AMB Based Systems Using Multirate and Nonuniform Sampling Proceedings of ISMB11  
Abstract: Different adaptive control algorithms have been developed for attenuating vibrations on AMB systems. The main aim of this work is to introduce the use of multirate and nonuniform sampling methods reducing the mean sampling rate, with the objective of minimizing the execution time of such algorithms. In particular, the proposed one is a feedforward adaptive vibration controller which generates sinusoidal signals whose amplitudes and phases are updated by the adaptation algorithm. This update is at different sampling times in the multirate version and at randomized sampling times, for the nonuniform sampling version. Such signals are applied to an AMB system obtaining, as expected, a minimization of the vibrations. Experimental results show the effectiveness of the adaptive control approach, allowing an important increment in the mean sampling period and leading to a reduced calculation time. Keywords- Adaptive control, AMB, vibration elimination, nonuniform sampling
BibTeX:
@inproceedings{ISMB11_7,
  author = {Josu Jugo and Inigo Arredondo},
  title = {Adaptive Control for Attenuating Vibrations in AMB Based Systems Using Multirate and Nonuniform Sampling},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_7.pdf}
}
2008 Chen, X., Liu, K. and Xiao, K. A Novel Controller with Force Feedback of Active Magnetic Bearings Proceedings of ISMB11  
Abstract: A novel force feedback controller is presented to overcome disturbing forces acting on magnetic suspended rotors of Active or Hybrid Magnetic Bearings (AMB or HMB). As there is linear relationship between disturbing forces and changes of magnetic field on bearings’ operating point, the force feedback is implemented by measuring bearings’ magnetic flux density by hall components. Detailed analysis is discussed also, the dynamic stiffness and damping of the controlled plant are increased when force feedback added into the controller; meanwhile, dynamic response of power amplifier is improved as the novel controller provides a zero point that counteract with the pole point of the power amplifier. A novel controller is developed based on conventional PID leading correcting network. Both simulation and experiment indicate that this novel controller can effectively decrease the influence of disturbing forces, and thus improves the controller’s performance.
BibTeX:
@inproceedings{ISMB11_70,
  author = {Xiaofei Chen and Kun Liu and Kai Xiao},
  title = {A Novel Controller with Force Feedback of Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_70.pdf}
}
2008 Ishikawa, T., ichi Matsuda, K., Masuzawa, T. and Kondo, R. 5-DOF Controlled Self-Bearing Motor Proceedings of ISMB11  
Abstract: A novel 5-DOF actively controlled self-bearing motor that combines the functions of a motor, two radial AMBs, and an axial AMB has been developed to achieve smaller size and higher performance simultaneously. In this paper, radial control performance of the developed self-bearing motor is evaluated by static and dynamic experiments. The radial control force and the negative stiffness due to the permanent magnets are measured statically. The dynamic performance was tested by measuring the impulse response and the frequency response and the maximum oscillation amplitude of the suspended rotor during rotation. The developed 5-DOF self-bearing motor displays sufficient radial position controllability.
BibTeX:
@inproceedings{ISMB11_71,
  author = {Tatsuya Ishikawa and Ken-ichi Matsuda and Toru Masuzawa and Ryou Kondo },
  title = {5-DOF Controlled Self-Bearing Motor},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_71.pdf}
}
2008 Ueno, S., ichi Uematsu, S. and Kato, T. Development of a Lorentz-Force-Type Slotless Self-Bearing Motor Proceedings of ISMB11  
Abstract: Magnetic bearings have advantages such as no friction loss, no abrasion, and lubrication-free operation. However they are not widely used due to their high cost and large size. In order to solve these problems, a self-bearing motor having a simple structure with distributed windings is proposed. The rotor consists of a permanent magnet and an iron yoke, which rotate in a body. The stator consists of a six-phase distributed winding and is installed between a permanent magnet and a back yoke of the rotor. A Lorentz force is generated by the stator current, and the rotation speed and radial position of the rotor are controlled by this force. In this study, the rotating torque and bearing force are analyzed theoretically, and a method for their control is discussed. A simple experiment confirms that the proposed self-bearing motor can be realized.
BibTeX:
@inproceedings{ISMB11_72,
  author = {Satoshi Ueno and Shin-ichi Uematsu and Takahisa Kato},
  title = {Development of a Lorentz-Force-Type Slotless Self-Bearing Motor},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_72.pdf}
}
2008 Kauss, W., Gomes, A., Stephan, R. and David, D. LQR Control of a Bearingless Machine Implemented with a DSP Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_73,
  author = {Wilmar Kauss and Afonso Gomes and Richard Stephan and Domingos David},
  title = {LQR Control of a Bearingless Machine Implemented with a DSP},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_73.pdf}
}
2008 Cao, X., Deng, Z., Yang, G. and Wang, X. Independent Control of Torque and Radial Force in Bearingless Switched Reluctance Motors Proceedings of ISMB11  
Abstract: Radial force and torque are the control objectives which determine the machine performance of levitation and rotation in a bearingless switched reluctance motor (BSRM). This paper proposes a control scheme for rotating and levitating a 12/8 BSRM. The motor torque and radial force are independently controlled with hybrid excitations in main windings and levitation windings. Firstly, the mathematical relationship between radial force and currents, which is utilized in this work, is derived with Maxwell stress tensor method. Then the proposed control scheme is analyzed. The average torque of each phase generated in levitation region equals to zero for its symmetry of the aligned position. Accordingly, the current calculating algorithm is deduced to minimize the magnitude of instantaneous torque in levitation region. The principle and realization of the proposed scheme are demonstrated with FE analysis. Experimental results show that the proposed scheme is effective for a stable levitation.
BibTeX:
@inproceedings{ISMB11_74,
  author = {Xin Cao and Zhiquan Deng and Gang Yang and Xiaolin Wang},
  title = {Independent Control of Torque and Radial Force in Bearingless Switched Reluctance Motors},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_74.pdf}
}
2008 Sun, F. and Oka, K. Zero Power Control for Permanent Magnetic Suspension System Proceedings of ISMB11  
Abstract: This paper describes a permanent magnetic suspension system that consists mainly of a permanent magnet, an actuator and sensors. This magnetic suspension system is based on a zero power control method, which results in almost no power consumption in the equilibrium state. Aspring is installed in the magnetic suspension device to counterbalance the force of the actuator on the mass gravitation in the equilibrium position. An integral feedback loop is used in the controller to achieve zero actuator current when the device is in a balance state. A model was set up for feasibility analysis, a prototype was manufactured for experimental confirmation, numerical simulations for the zero power control were carried out based on the model, and experiments were completed for practice confirmation using the prototype. Some results of simulations and experiments are shown and analyzed here, and conclusions based on these results are given.
BibTeX:
@inproceedings{ISMB11_75,
  author = {Feng Sun and Koichi Oka},
  title = {Zero Power Control for Permanent Magnetic Suspension System},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_75.pdf}
}
2008 Boeij, J.D. and Lomonova, E. Experimental Verification of Look-Up Table Based Real-Time Commutation of 6-DOF Planar Actuators Proceedings of ISMB11  
Abstract: The control of contactless magnetically levitated planar actuators with stationary coils, moving magnets and 6-DOF is very complicated. In contradiction to normal synchronous AC machines the forces and torques cannot be decoupled using a sinusoidal commutation scheme. Instead, a feedback linearization law has to be applied as commutation scheme that decouples the forces and torques and calculates the required currents to realize the desired forces and torques of the magnetic suspension. This feedback linearization law is based on the coupling matrix that links the current in each coil to the force and torque vector on the actuator. The accurate calculation of this coupling matrix in real-time is critical for controlling the planar actuator. In this paper a look-up table based method is used to apply feedback linearization and the performance of the algorithm is verified with measurements.
BibTeX:
@inproceedings{ISMB11_76,
  author = {Jeroen De Boeij and Elena Lomonova},
  title = {Experimental Verification of Look-Up Table Based Real-Time Commutation of 6-DOF Planar Actuators},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_76.pdf}
}
2008 Furutachi, M., Inaba, S., Takasaki, M., Ishino, Y. and Mizuno, T. Experimental Study on the Basic Characteristic of Flux Path Control Magnetic Suspension Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_77,
  author = {Munehiro Furutachi and Shunsuke Inaba and Masaya Takasaki and Yuji Ishino and Takeshi Mizuno},
  title = {Experimental Study on the Basic Characteristic of Flux Path Control Magnetic Suspension},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_77.pdf}
}
2008 Tian, J., Wang, Y., Zhao, H., Zhang, P. and Huang, W. Geometrical Design for a Large Magnetic Supporting System Considering Coupling Effect Proceedings of ISMB11  
Abstract: Large magnetic supporting system is a typical magnetic machine, and it would bring greater errors by conventional method to design its structural and electromagnetic parameters. This paper uses coupled field-circuit design method, against the present design methods’ defects, to provide interaction design method of structural and electromagnetic parameters by the electromagnetic parameters, structural strength and stiffness design and analysis on supporting system components, and verify the feasibility of such design method.
BibTeX:
@inproceedings{ISMB11_78,
  author = {Jie Tian and Yong Wang and Han Zhao and Ping Zhang and Wenting Huang},
  title = {Geometrical Design for a Large Magnetic Supporting System Considering Coupling Effect},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_78.pdf}
}
2008 Sakai, S., Kuriyama, K. and Nonami, K. A Novel Passivity Based Control without Conventional Cross Feedback Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_79,
  author = {Satoru Sakai and Kenta Kuriyama and Kenzo Nonami},
  title = {A Novel Passivity Based Control without Conventional Cross Feedback},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_79.pdf}
}
2008 Cole, M.O.T. Model-Free Control Methods for Recovery from Touchdowns Involving Circular Whirl Proceedings of ISMB11  
Abstract: In this paper, the dynamics associated with rotor-stator touchdowns involving full circular rub are considered. The expected range of phase shifts occurring in various measurable signals are examined from a theoretical standpoint, with the aim of developing model-free control algorithms that can recover contact-free rotor levitation from a state involving persistent rub with touchdown bearings. Two different strategies are proposed, according to whether touchdowns planes can be considered collocated with the AMBs or not. Requirements for successful operation, in terms of available sub-models and measurement information, as well as possible deficiencies are explained and verified through experimental tests on a multi-mode flexible rotor test rig.
BibTeX:
@inproceedings{ISMB11_8,
  author = {Matthew O. T. Cole},
  title = {Model-Free Control Methods for Recovery from Touchdowns Involving Circular Whirl},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_8.pdf}
}
2008 Vadillo, J., Echeverria, J.M., Elosegui, I. and Fontan, L. An Approach to a 3-pole Active Magnetic Bearing System Fed by a Matrix Converter Proceedings of ISMB11  
Abstract: This paper presents a MATLAB/Simulink model for a 3-pole radial magnetic bearing system that is fed by a matrix converter (MC). The active magnetic bearings (AMBs) system model that is studied here is shown and tested in [1] using a simplified inverter model, so that the main contribution of this paper lies in the simulation, study and analysis of the AMBs performance under a MC supply. In order to achieve this objective, a more complex inverter model, including the rectifier stage, and a MC model are implemented, analysed and compared in conjunction with the bearings. Results from models described in [1] are taking into consideration in order to verify the new models performance.
BibTeX:
@inproceedings{ISMB11_80,
  author = {Javier Vadillo and Jose Martin Echeverria and Ibon Elosegui and Luis Fontan},
  title = {An Approach to a 3-pole Active Magnetic Bearing System Fed by a Matrix Converter},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_80.pdf}
}
2008 Kuriyama, K., Nonami, K. and Rachmanto, B. Attitude Stabilization Control of AMB-Flywheel Supported by Two-Axes Gimbals Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_81,
  author = {Kenta Kuriyama and Kenzo Nonami and Budi Rachmanto},
  title = {Attitude Stabilization Control of AMB-Flywheel Supported by Two-Axes Gimbals},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_81.pdf}
}
2008 Lantto, E. and Tommila, V. A Supercritical 250 kW Industrial Air Compressor Prototype Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_82,
  author = {Erkki Lantto and Ville Tommila},
  title = {A Supercritical 250 kW Industrial Air Compressor Prototype},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_82.pdf}
}
2008 Bian, B., Liu, S., Li, D. and Maslen, E. Automatic Thermal Expansion Compensation of the AMB Used in Precision Grinding Machine Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_83,
  author = {Bin Bian and Shuqin Liu and Deguang Li and Eric Maslen},
  title = {Automatic Thermal Expansion Compensation of the AMB Used in Precision Grinding Machine},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_83.pdf}
}
2008 Izpizua, A., Almandoz, X., Martin, M.S., Cantero, D. and Perez, I. Design and Manufacturing of a 70 kW, 36000 rpm Milling Spindle Proceedings of ISMB11  
Abstract: This work shows the development of magnetically levitated high speed spindles and the possibilities they give for the interaction with the milling process. A fully magnetically levitated spindle with 70 kW up to 36000 rpm is presented; its design and manufacturing issues and his performance in comparison with conventional high speed spindles. Furthermore the possibility to estimate cutting forces and parameters by an state-space approach, using the internal signals of the magnetic bearings as a whole adaptronic system, is shown; and even some preliminary attempts of damping process vibrations.
BibTeX:
@inproceedings{ISMB11_84,
  author = {Alberto Izpizua and Xanti Almandoz and Manex San Martin and David Cantero and Ion Perez},
  title = {Design and Manufacturing of a 70 kW, 36000 rpm Milling Spindle},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_84.pdf}
}
2008 Diao, X. and Yu, S. Preliminary Tests for the HTR-10 Helium Circulator with the Active Magnetic Bearings Proceedings of ISMB11  
Abstract: The Helium circulator is one of the key equipment of the high temperature gas-cooled reactor (HTR), which directs helium to flow through the reactor core and the steam generator to achieve the thermal energy transfer between them. At present, there are two optional schemes in the design of the helium circulator. One is the dry gas seal, another is the active magnetic bearing (AMB), but both of them haven’t been used in the reactors beforetime. After the 10 MW High Temperature Gas-cooled Reactor-Test Module (HTR-10) was brought to criticality in December of 2000, Institute of Nuclear and New Energy Technologies (INET) of Tsinghua University dedicated to upgrade the technology of the helium circulator. It takes 3 years to manufacture a helium circulator with the active magnetic bearings in Shanghai Blower Factory, which has the same rated parameters as the one of HTR-10. It stood all the tests in November of 2007, including the 100 hour test at the conditions of high temperature(250°C) and high speed (5000r/min). All of these means INET made a great progress in the area of the active magnetic bearing technology. This circulator will be installed to HTR-10 to endure the further tests at the reactor conditions such as high temperature, radiation, graphite dust and the inert helium atmosphere. In the foundation of these successful tests, the design of the larger scale and higher power level helium circulator with AMBs for the HTR-PM project will enter the official implementation stage. This paper covers the philosophy behind the design and descriptions of the HTR-10 helium circulator and the preliminary tests. Significantly useful information is also derived from temperature distribution in the AMBs.
BibTeX:
@inproceedings{ISMB11_85,
  author = {Xingzhong Diao and Suyuan Yu},
  title = {Preliminary Tests for the HTR-10 Helium Circulator with the Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_85.pdf}
}
2008 Filatov, A., Hawkins, L., Krishnan, V. and Lam, B. Active Axial Electromagnetic Damper Proceedings of ISMB11  
Abstract: In magnetic bearing applications with rather limited axial loads and/or relaxed requirements for the axial positioning accuracy of the rotor it can be attractive to achieve the axial suspension using passive reluctance centering. In this case, however, it might be difficult to obtain the damping necessary to limit transient response to unexpected dynamic loads. A concept of an active electromagnetic axial damper developed for a 1MW 15,000RPM motor on magnetic bearings with passive axial reluctance centering is presented. The damper features a PM-biased actuator with a flux feedback. Using the flux feedback allows reducing the negative axial stiffness of the actuator to a level sufficient for using it in combination with a passive axial bearing exhibiting rather low positive axial stiffness 2400 lbf/in (420kN/m). The other advantages of the flux feedback include more linear relationship between the output force and the control command than in conventional current control as well as significant reduction of the gain and phase roll offs caused by the eddy currents. The design delivers 8760 Ns/m damping coefficient, which represents 20% of the critical damping, and 670N load capacity sufficient to address the worst-case-scenario dynamic response.
BibTeX:
@inproceedings{ISMB11_86,
  author = {Alexei Filatov and Larry Hawkins and Venky Krishnan and Bryan Lam},
  title = {Active Axial Electromagnetic Damper},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_86.pdf}
}
2008 Cantero, D., Izpizua, A., Mabe, J., Perez, I. and Arana, J. Hardware Platform for Magnetic Bearing Control in Machine-Tool Applications Proceedings of ISMB11  
Abstract: In this paper a new and powerful control hardware for magnetic spindle applications is presented. The Hardware consists in two boards. The processor board assembles a floating point DSP, a high density FPGA and a TCP/IP communication Module. It is in charge of the control algorithms processing, system monitoring and real time data acquisition. The interface board assembles all the hardware modules needed to access external devices such as digital I/O, ADCs and DACs, encoder modules and so on. Moreover the most prominent features of the hardware devices and the reasons that have motivated the new design are described. Since control strategy imposes computation requirements, a brief description of control algorithms is included. How this algorithm is distributed along the processor device is discussed as an example for control software implementation in the new hardware. Finally, the new hardware design performance and benefits are enumerated and future work is presented.
BibTeX:
@inproceedings{ISMB11_87,
  author = {David Cantero and Alberto Izpizua and Jon Mabe and Ion Perez and Joseba Arana},
  title = {Hardware Platform for Magnetic Bearing Control in Machine-Tool Applications},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_87.pdf}
}
2008 Okuhata, T., Isomura, N. and Komori, M. New Type of Self-sensing Magnetic Bearing Using Resonant Circuits for Liquid Nitrogen Pump Proceedings of ISMB11  
Abstract: Self-sensing magnetic bearings don’t have any position sensors. For this reason, self-sensing magnetic bearings are very promising for the maintenance free. They are useful for hydrogen pumps for rocket engines and hydrogen station of the fuel cars. Our self-sensing magnetic bearing gets the rotor position information from the middle point voltage. The control of levitation was performed by using this voltage. In this study, we propose a new type of self-sensing magnetic bearing technique and study the characteristics. And we verified that the self-sensing technique is useful in the extremely low temperature.
BibTeX:
@inproceedings{ISMB11_88,
  author = {Taro Okuhata and Naoki Isomura and Mochimitsu Komori},
  title = {New Type of Self-sensing Magnetic Bearing Using Resonant Circuits for Liquid Nitrogen Pump},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_88.pdf}
}
2008 Herzog, R., Amstad, R., Vullioud, S., Galdos, G., Muellhaupt, P. and Longchamp, R. Self-Sensing of Nonlaminated Axial Magnetic Bearings : Modelling and Validation Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_89,
  author = {Raoul Herzog and Roman Amstad and Sebastien Vullioud and Gorka Galdos and Philippe Muellhaupt and Roland Longchamp},
  title = {Self-Sensing of Nonlaminated Axial Magnetic Bearings : Modelling and Validation},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_89.pdf}
}
2008 Hyeong-Joon, A. Dynamic Performance Limitation in Driving a Radial AMB with Space Vector PWM Proceedings of ISMB11  
Abstract: This paper presents a new modeling method and a control system design procedure for a flexible rotor with many elastic modes by using active magnetic bearings. The purpose of our research is to rotate the rotor for passing through critical speeds caused by flexible modes. To achieve this, it is necessary to control motion and vibration of the flexible rotor simultaneously. The new modeling method named as Extended Reduced Order Physical Model is presented to express its motion and vibration uniformly. By using this model, a PID (Proportional-Integral-Derivative) controller to levitate the rotor and a LQ (Linear-Quadratic) controller to suppress its vibration are designed.
BibTeX:
@inproceedings{ISMB11_9,
  author = {Ahn Hyeong-Joon},
  title = {Dynamic Performance Limitation in Driving a Radial AMB with Space Vector PWM},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_9.pdf}
}
2008 Lu, X., Paone, M., ur-rab Usman, I. and Slocum, A.H. Linear Magnetic Bearings/Actuator Design and Prototype for High Precision Spindles Proceedings of ISMB11  
Abstract: In precision manufacturing, magnetic thrust bearings can be advantageously used to provide both high axial stiffness and short-stroke axial in-feed motion for precision spindles. This paper presents the design, analysis, prototype, and experimental results of a compact radially-biased magnetic thrust bearing with linear force characteristics. The first prototype of the thrust magnetic bearing demonstrates less than 5 nm RMS positioning noise over 1 mm stroke and 1500 Hz closed-loop bandwidth. The actuating force is over 300 N at continuous working condition and a maximum of 600 N.
BibTeX:
@inproceedings{ISMB11_90,
  author = {Xiaodong Lu and Matthew Paone and Irfan-ur-rab Usman and Alexander H. Slocum},
  title = {Linear Magnetic Bearings/Actuator Design and Prototype for High Precision Spindles},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_90.pdf}
}
2008 Kurosu, H., Masuzawa, T., Katoh, A., Suzuki, K., Onuma, H. and Kakihara, K. Wide Gap Magnetic Bearing System for a Magnetically Suspended Clean Pump Proceedings of ISMB11  
Abstract: A new hybrid magnetic bearing and motor system for magnetically suspended clean pumps with wide air gaps has been developed. The permanent magnet geometry is examined by three dimensional magnetic field analysis with the finite element method. The optimization method to determine the optimal values of the design parameters has been developed based on magnetic equivalent circuit technique, genetic algorithm (GA) and three dimensional magnetic field analysis. The size of the hybrid magnetic bearing C core, the thickness of the permanent magnets, and the turn number of the electromagnets are optimized by the method. The designed HM bearing and motor system has an outer diameter of 100 mm, a length of 140 mm, and air gaps of 3.5 mm. The optimized system produces a target attractive force of 20 N with an excitation current of 0.5 A and the ratio of force to excitation current is 40 N/A. The devised hybrid magnetic bearing indicates sufficient bearing performance for the target clean pump and the developed optimization method displayed sufficient ability to design the hybrid magnetic bearing.
BibTeX:
@inproceedings{ISMB11_91,
  author = {Hiroaki Kurosu and Toru Masuzawa and Ayako Katoh and Kenich Suzuki and Hiroyuki Onuma and Kouichi Kakihara},
  title = {Wide Gap Magnetic Bearing System for a Magnetically Suspended Clean Pump},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_91.pdf}
}
2008 Na, U.J., Kang, H.O., Lee, D.D. and Seo, K.H. Design and Analysis of New Permanent Magnet Biased Heteropolar Magnetic Bearings Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_92,
  author = {Uhn Joo Na and Hyun Ok Kang and Dong Dae Lee and Kyung Hwan Seo},
  title = {Design and Analysis of New Permanent Magnet Biased Heteropolar Magnetic Bearings},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_92.pdf}
}
2008 Wu, H., Wang, X., Wei, L. and Hu, Y. Design and Realization of Magnetic Suspended Device Based on Edge Effect Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_93,
  author = {Huachun Wu and Xiaoguang Wang and Li Wei and Yefa Hu},
  title = {Design and Realization of Magnetic Suspended Device Based on Edge Effect},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_93.pdf}
}
2008 Bosgiraud, T., Chapuis, D., Barrot, F. and Bleuler, H. Overcoming of High Centrifugal Forces in a 5 DOF Micro AMB Gyroscope Proceedings of ISMB11  
Abstract: The need for motion sensing system is constantly growing for civil and mass applications, which require products that ally precision, low cost and compactness. The active magnetic bearing (AMB) technology because of its absence of friction between the rotor and the stator could be an interesting solution to reach the two first requirements. The miniaturization of the AMB system permits to satisfy the last one. Among other sensing devices, gyroscopes can benefit from the high spinning speeds of the rotor that AMB permit. These high speeds guarantee the high precision of the instrument. However, these high speeds have the inconvenience of destabilizing the rotor. Therefore, a good control of the rotor position is a key issue towards a precise gyroscope. On that purpose, this paper presents a two degrees of freedom Hinf controller based on the GS/T weighting scheme strategy and including an explicit integrative part. The simulations run with that controller show a great improvement in the quality of the angular velocity measurements compared to a classical two degrees of freedom Hinf controller as will be shown in this paper.
BibTeX:
@inproceedings{ISMB11_94,
  author = {Thomas Bosgiraud and Dominique Chapuis and Francois Barrot and Hannes Bleuler},
  title = {Overcoming of High Centrifugal Forces in a 5 DOF Micro AMB Gyroscope },
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_94.pdf}
}
2008 Fukata, S. A Model of Magnetic Reluctance of Cylindrical Solid Iron Cores Proceedings of ISMB11  
Abstract: A model of magnetic reluctance is considered in the frequency domain for cylindrical solid iron-cores when magnetic flux normally enters and leaves on the circumferential surface. To have an analytical model, we take a iron core that is sufficiently high to spread the magnetic flux over the circumferential surface and not out over the upper and lower ends. First, a three-dimensional distribution of the magnetic field is solved with Laplace transform. Then, the magnetomotive force between the two pole faces is obtained by a mean value along flux paths on the surface to describe the magnetic reluctance. The model given by Bessel functions is approximated in a simple form. The numerical result is compared with an experimental result to check the applicability of the model to actual cores.
BibTeX:
@inproceedings{ISMB11_95,
  author = {Satoru Fukata},
  title = {A Model of Magnetic Reluctance of Cylindrical Solid Iron Cores },
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_95.pdf}
}
2008 Hynynen, K., Jastrzebski, R. and Pöllänen, R. Identification and Modeling of AMB Rotor System Using Complex Lead and Lag Compensator Structures Proceedings of ISMB11  
Abstract: Control design of AMB rotor system demands very accurate system model. Modeling of the rotor is traditionally made using Finite Element Method (FEM) or Experimental Modal Analysis (EMA), but Active Magnetic Bearings (AMB) offer a possibility to obtain the model using system identification. The purpose of this study is to identify the flexible modes of the rotor and determine its transfer function model using complex lead and lag compensator structures. The results demonstrate that the proposed method suits for modeling the flexible modes of an AMB rotor system.
BibTeX:
@inproceedings{ISMB11_96,
  author = {Katja Hynynen and Rafal Jastrzebski and Riku Pöllänen},
  title = {Identification and Modeling of AMB Rotor System Using Complex Lead and Lag Compensator Structures},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_96.pdf}
}
2008 Kluyskens, V. and Dehez, B. Analysis of a Dynamical Electromechanical Model for Magnetic Bearings with Induced Currents Proceedings of ISMB11  
Abstract: The purpose of this paper is to present a parameterized electromechanical model considering as well the electromagnetic nature of the forces acting inside a magnetic bearing as the general rotating machinery aspects, and their interactions. This model takes particularly the effect of induced currents into account. The inductive and resistive effects, as well as the skin effect taking place in the bearing are considered. The model is validated on an existing semi-passive magnetic bearing.
BibTeX:
@inproceedings{ISMB11_97,
  author = {Virginie Kluyskens and Bruno Dehez},
  title = {Analysis of a Dynamical Electromechanical Model for Magnetic Bearings with Induced Currents},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_97.pdf}
}
2008 Park, Y.H., Park, I.H., Jang, H.D. and Han, D.C. A Novel Self-Sensing Technology of Active Magnetic Bearings Using a High Frequency Voltage Injection Method Proceedings of ISMB11  
Abstract: Conventional AMBs (active magnetic bearings) systems consist of electromagnetic coils, position sensors, power amplifiers and a feedback controller. This hardware configuration can lead to a structural complexity, problems of space limitations for the installation. In this paper, a self-sensing mechanism is proposed to resolve such limitations of the general AMB system. The proposed self-sensing scheme uses a phase difference of the injected current of two opposite electromagnetic actuators while an object levitating between the actuators. The relationship between the phase difference of injected currents and the position of a levitated object was theoretically derived and linearized. In order to realize the proposed self-sensing scheme, a signal processing algorithm was developed. The frequency response of the estimator was measured to verify the performance of the proposed self-sensing scheme. In addition, a magnetic levitation and a disturbance rejection response were experimentally obtained to verify the feasibility of the proposed self-sensing mechanism. Experimental results showed that the developed self-sensing technique has similar performance as a practical gap sensor.
BibTeX:
@inproceedings{ISMB11_98,
  author = {Young Ho Park and In Hwang Park and Hee Doh Jang and Dong Chul Han},
  title = {A Novel Self-Sensing Technology of Active Magnetic Bearings Using a High Frequency Voltage Injection Method},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_98.pdf}
}
2008 Hofer, M. and Schroedl, M. Test Bench for Three Phase Permanent Magnet Biased Radial AMBs with a Sensorless Control Strategy Based on INFORM Method Proceedings of ISMB11  
Abstract: In this paper a test bench for permanent magnet biased radial Active Magnetic Bearing (AMB) with respect to a sensorless control strategy based on INFORM method is presented. The purpose of this Hybrid Magnetic Bearing (HMB) prototype is to research the capability of the INFORM method for sensorless control of HMBs. The well known INFORM method for sensorless control of Permanent Magnet Synchronous Motors (PMSM) is adapted for the HMB and also described in principle. For the test bench a three phase MOSFET inverter was build up. First measurement results of the INFORM capability are presented.
BibTeX:
@inproceedings{ISMB11_99,
  author = {Matthias Hofer and Manfred Schroedl},
  title = {Test Bench for Three Phase Permanent Magnet Biased Radial AMBs with a Sensorless Control Strategy Based on INFORM Method},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_99.pdf}
}
2008 Bleuler, H. 20 Years ISMB: Then, Now, Future Proceedings of ISMB11  
Abstract: No abstract available, please see full pdf.
BibTeX:
@inproceedings{ISMB11_key01,
  author = {Hannes Bleuler},
  title = {20 Years ISMB: Then, Now, Future},
  booktitle = {Proceedings of ISMB11},
  year = {2008},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb11/ismb11_submission_key01.pdf}
}
2006 Wang, X., Deng, Z., Liao, Q. and Qiu, Z. The Simulation of Novel Bearingless Consequent-pole Slice Motor Proceedings of ISMB10  
Abstract: In the bearingless slice motor, two radial degrees magnetic levitation is realized by utilizing bearingless technology. Meanwhile three out of five degrees can be stabilized passively. In this paper, a novel bearingless slice motor is proposed. The levitation control is independent of the drive-winding magnetic field. This paper introduces the principle of radial force, as well as the advantages of the motor. Furthermore, the equations of radial levitation force are given. At last, the main levitation characteristics of the novel machine are analyzed by using 2D/3D finite element analysis in detail. The results verify the validity of the proposed motor.
BibTeX:
@inproceedings{ISMB10_1,
  author = {Xiaolin Wang and Zhiquan Deng and Qixin Liao and Zhijian Qiu },
  title = {The Simulation of Novel Bearingless Consequent-pole Slice Motor},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_1.pdf}
}
2006 Lang, M. and Lembke, T.A. Design of Permanent Magnet Bearings with high stiffness Proceedings of ISMB10  
Abstract: The stiffness of permanent magnet bearings, PMB’s, composed of only two magnet rings is limited, and it is well known that increasing the size of these magnets by increasing their cross section area has a very limited effect on bearing performance. Instead, in order to gain enough stiffness, axially stacked structures of comparatively smaller permanent magnets are frequently being used. By arranging the magnets with alternating polarity, the flux derivatives as well as the bearing stiffness are known to be increased.
BibTeX:
@inproceedings{ISMB10_10,
  author = {Matthias Lang and Torbjörn A. Lembke},
  title = {Design of Permanent Magnet Bearings with high stiffness},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_10.pdf}
}
2006 Adler, K., Schalk, C., Nordmann, R. and Aeschlimann, B. Active Balancing of a Supercritical Rotor on Active Magnetic Bearings Proceedings of ISMB10  
Abstract: Balancing of rotors needs a lot of manpower, specific knowledge and is time-consuming. In the rising field of high speed machinery also the requirements for suitable effective balancing concepts increase. Here a combination of active magnetic bearings (AMBs) and active balancing devices (ABDs) on a supercritical rotor creates the possibility for a partial automation of the balancing process. That way critical rotor speeds can be passed and the time effort for the balancing process can be reduced significantly.
BibTeX:
@inproceedings{ISMB10_11,
  author = {Kai Adler and Christoph Schalk and Rainer Nordmann and Beat Aeschlimann},
  title = {Active Balancing of a Supercritical Rotor on Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_11.pdf}
}
2006 Kim, H.-Y. and Kim, S.-J. An Effective Way to Combine Radial and Axial Magnetic Bearings in a Unit Proceedings of ISMB10  
Abstract: This paper proposes a new way to combine radial and axial active magnetic bearingsin a unit. The proposed active magnetic bearing (AMB) has no large axial disk and instead use the Lorentz force for axial control. Thus this AMB system can be more compact. Its structure is basically similar to the homopolar AMB with four cores circumferentially connectedby yokes. But it has two-layer windings for radial and axial controls; one is configured like a homopolar AMB, and the other is the same as that of a 4-pole heteropolar AMB. Since each winding can be used for radial control, the proposed system has two kinds of operating principle according to the radial control type. As for axial control action, it uses the Lorentz force generated by the interaction of the bias flux for radial control and the axial control flux. The feasibility of this scheme is experimentally verified by using a simple PD controller with a feedforward loop.
BibTeX:
@inproceedings{ISMB10_12,
  author = {Ha-Yong Kim and Seung-Jong Kim},
  title = {An Effective Way to Combine Radial and Axial Magnetic Bearings in a Unit},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_12.pdf}
}
2006 Kwak, H.-S. and Kim, S.-J. A Self-bearing Motor with a Passively Levitated Rotor Proceedings of ISMB10  
Abstract: This paper proposes a passive self-bearing motor which combines two switched reluctance motors and a passive magneticbearing (PMB) based on the repulsion between permanent magnets. Its structural feature is that the cores of the motor, which are attached on both sides of the PMB, are also utilized as flux paths for permanent magnets. For a strong levitation force,the permanent magnets of PMB are stacked like Halbach array, and for rotation, it works just likea switched reluctance motor. Compared with conventional self-bearing motors which are mostly based on the theory of active magnetic bearings, the proposed self-bearingmotor has a very simple and small structure, and the production costis very low. Through some FEM analysis results, the feasibility of the proposed motor was confirmed and the design parameters were determined.
BibTeX:
@inproceedings{ISMB10_13,
  author = {Ho-Seong Kwak and Seung-Jong Kim},
  title = {A Self-bearing Motor with a Passively Levitated Rotor},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_13.pdf}
}
2006 Suzuki, H., Suzuki, A., Sasaki, S., Ito, A., Barrot, F., Chapuis, D., Bosgiraud, T., Moser, R., Sandtner, J. and Bleuler, H. Proto-model of novel contact-free disk suspension system utilizing diamagnetic material Proceedings of ISMB10  
Abstract: Technology of passive magnetic levitation using diamagnetic materials at room temperature is very important in various industry fields. Recently, we have designed and manufactured a novel ring Halbach permanent magnet array. And contact-free suspension and rotation of a diamagnetic graphite (PG: pyrolytic graphite) disk was realized on this proto-model ring Halbach PM array. In this paper, we mainly describe the design of both the novel ring permanent magnetic array and the graphite disk, and we shall report preliminary experimental result about a novel contact-free disk suspension.
BibTeX:
@inproceedings{ISMB10_14,
  author = {Haruhiko Suzuki and Atsushi Suzuki and Syuhei Sasaki and Atsushi Ito and François Barrot and Dominique Chapuis and Thomas Bosgiraud and Roland Moser and Jan Sandtner and Hannes Bleuler},
  title = {Proto-model of novel contact-free disk suspension system utilizing diamagnetic material },
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_14.pdf}
}
2006 Moser, R., Sandtner, J., Schoderet, A., Giovanola, J. and Bleuler, H. Design of Very High Speed Friction Spindle using Passive Magnetic Bearings Proceedings of ISMB10  
Abstract: Aiming at rotation speeds above 1 million rounds per minute, a two-stage motor device is hereby proposed, based on the concept of so-called false twisting aggregates, known from the yarn processing industry. The first stage, a synchronous machine, is designed around a passive magnetic bearing. The second stage, a small axis, spun by the first stage using a friction transmission is designed to find its physical limits around 7 million rounds per minute. This report presents the design of the experimental set-up. Based on finite element analysis, the performances of the future experimental set-up will be estimated.
BibTeX:
@inproceedings{ISMB10_15,
  author = {Roland Moser and Jan Sandtner and Alain Schoderet and Jacques Giovanola and Hannes Bleuler},
  title = {Design of Very High Speed Friction Spindle using Passive Magnetic Bearings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_15.pdf}
}
2006 Gruber, W. and Amrhein, W. Design of a Bearingless Segment Motor Proceedings of ISMB10  
Abstract: Active magnetic bearings and bearingless motors have begun to be used in industry and medical technology. When the rotor is short with respect to its diameter, it is possible to stabilize three degrees of freedom passively by reluctance forces. For this type of motor a new approach to a mechanical design is presented – the Bearingless Segment Motor. This paper deduces a model of the new motor for current injection. Finite element simulations allow the optimisation of force and torque, the reduction of cogging torque and reluctance forces as well as the consideration of the passive radial and passive axial stiffness. However, the force distribution and the mathematical model are nonlinear. Therefore a suitable nonlinear control scheme is presented. The introduction of a prototype and first measurements complete the paper.
BibTeX:
@inproceedings{ISMB10_16,
  author = {Wolfgang Gruber and Wolfgang Amrhein },
  title = {Design of a Bearingless Segment Motor},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_16.pdf}
}
2006 Okada, Y., Jinbu, T., Yamashiro, N. and Sagawa, K. Lorentz Type Self-Bearing Motor using Halbach Magnets Proceedings of ISMB10  
Abstract: This paper proposes a 4-pole outer rotor type self-bearing motor which uses Lorentz force with Halbach magnet. It is expected to have good dynamic response and high levitation capability. For realizing high magnetic flux in airgap, Halbach magnet is used for the rotor. First, previous model of 8-pole motor is introduced and the associated problems are summarized. That is, the control forces for x and y directions were quite different and the levitation was unstable. For stable levitation, two sets of three phase coils were used and the system became complex. To overcome these problems, a new 4-pole and three segmented Halbach magnets are introduced. The fundamental principle is explained how the motor produces rotating torque and radial levitation forces. Finally, the motor is designed and fabricated. The levitated rotating test was carried out successfully. The top speed of 7400 [rpm] and the maximum motor efficiency of 72 [%]were recorded.
BibTeX:
@inproceedings{ISMB10_17,
  author = {Yohji Okada and Takuro Jinbu and Naoto Yamashiro and and Kouji Sagawa},
  title = {Lorentz Type Self-Bearing Motor using Halbach Magnets},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_17.pdf}
}
2006 Herrmann, M. and Ulbrich, H. Studies on Coil-less Reluctance Force Actuators Proceedings of ISMB10  
Abstract: Flux control in magnetic actuators can be achieved by additional field superposition or flux path ma-nipulation. Usually, coils are used for external flux control, but inductance lags and ohmic losses degrade actuator effi-ciency. To design energy-efficient reluctance force actuators innovative concepts for controlling the magnetic flux without coils are investigated. On the one hand, this contribution deals with variable reluctance elements based on the in-verse magnetostrictive effect. On the other, magnetic flux is redirected in the magnetic circuit by means of small displacements of reluctance switch elements. For high ma-nipulation rates these elements feature cog-slot structures. Some general design rules are outlined and two examples of application are presented. An active magnetic bearing and a bidirectional actuator are simulated and compared to a bipolar electromagnetic actuator. Finally, all results show the capability of coil-less reluctance force actuators to outperform present electromagnetic systems in terms of bandwidth and energy balance.
BibTeX:
@inproceedings{ISMB10_18,
  author = {Marcus Herrmann and Heinz Ulbrich},
  title = {Studies on Coil-less Reluctance Force Actuators},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_18.pdf}
}
2006 Ooshima, M. A Magnetic Suspension Control Strategy of Bearingless Motors with 2-phase Brushless DC Structure Proceedings of ISMB10  
Abstract: This paper presents a new structure of bearingless motor whose function is applied in a 2-phase brushless DC motor. The proposed structure is illustrated and the principle of suspension force generation and magnetic suspension control strategy are found to suspend the rotor stably without mechanical contact. The rotational torque and suspension force are computed by Finite Element Method (FEM) using a machine model. It is found in the computed results thatthe mutual interference occurs between the suspension forces in two perpendicular radial axes. The methods to decrease the mutual interference are proposed. The validity proposed control strategy is confirmed through the computed results by FEM.
BibTeX:
@inproceedings{ISMB10_19,
  author = {Masahide Ooshima},
  title = {A Magnetic Suspension Control Strategy of Bearingless Motors with 2-phase Brushless DC Structure},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_19.pdf}
}
2006 Barrot, F., Burns, B., Chapuis, D., Bosgiraud, T. and Bleuler, H. Position controlled diamagnetic linear conveyor Proceedings of ISMB10  
Abstract: In micro-factories mini-conveyors will be used to convey small parts and components between storage, production and assembly units. Since a clean environment as well as a low power consumption are some of the prerequisites for a micro-factory, it is essential that mini-conveyors used in such an application respect these requirements. In the present article the authors propose a new kind of position controlled conveyor that meets these conditions.
BibTeX:
@inproceedings{ISMB10_2,
  author = {Francois Barrot and Benjamin Burns and Dominique Chapuis and Thomas Bosgiraud and Hannes Bleuler},
  title = {Position controlled diamagnetic linear conveyor},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_2.pdf}
}
2006 Gomes, R.R., Stephan, R.M. and Santisteban, J. Self-bearing Motor with DSP Based Control System Proceedings of ISMB10  
Abstract: This paper presents an adaptive digital controller for a self-bearingmotor. The controller is implemented using a DSP platform. Initially, the motor operation is explained and a mathematical model derived. The optimized performance is achieved adjusting the controller parameters as a function or the rotor angular speed. Finally, some characteristics of the DSP implementation are described.Key words– Bearingless machines, Magnetic bearings, High-speed electric motors, Feedback control systems, Emerging technologies.
BibTeX:
@inproceedings{ISMB10_20,
  author = {Rafael R. Gomes and Richard M. Stephan and Jose Santisteban},
  title = {Self-bearing Motor with DSP Based Control System},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_20.pdf}
}
2006 Li, C., Aratani, H. and Oka, K. Analysis of Bearingless Motor with Rectifier Circuits Proceedings of ISMB10  
Abstract: In this paper, feasibility studies for a new type of bearingless motor are carried out by FEM analyses and experiments. The feature of the bearingless motor is using a rotor with rectifier circuit coil, which makes the rotor act as a permanent magnet. The optimum geometrical dimensions of the proposed bearingless motor are determined by the calculations of rotor torques about various rotor tooth lengths. The results indicate that large enough torque can be generated. The dimension with which the motor has relatively minimum fluctuation and smoothness torque has been chosen to build a test model. In order to realize the radial forces and rotation control, a strategy which adopts sine and cosine control currents of rotor angle has been test. FEM analysis is also used for evaluating the property of the proposed strategy. The results show that the generated radial force fluctuates with the rotor angle, however, the linearity of the generated forces to control currents is verified, and feedback control can be used to reduce this problem.
BibTeX:
@inproceedings{ISMB10_21,
  author = {Chen Li and Hironobu Aratani and Koichi Oka},
  title = {Analysis of Bearingless Motor with Rectifier Circuits},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_21.pdf}
}
2006 Yamada, T., Chiba, A., Nakajima, A., Hoshino, T., Fukao, T., Takemoto, M., Oshima, M. and Ichikawa, O. Basic Characteristics of an Outer Rotor Consequent-pole Bearingless Drive Proceedings of ISMB10  
Abstract: An outer rotor consequent-pole bearingless drive is proposed with two-axis active position regulation having one unit of a bearingless motor. The other axis positions are supported by passive magnetic bearings. In this paper, basic characteristics are presented.
BibTeX:
@inproceedings{ISMB10_22,
  author = {Tomohiro Yamada and Akira Chiba and Atsushi Nakajima and Takeshi Hoshino and Tadashi Fukao and Masatsugu Takemoto and Masahide Oshima and Osamu Ichikawa},
  title = {Basic Characteristics of an Outer Rotor Consequent-pole Bearingless Drive},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_22.pdf}
}
2006 Stephens, L.S. and Carroll, D.J. Spherical Actuation Using the Displaced Trapezoidal Winding Proceedings of ISMB10  
Abstract: Previous work has shown that the segmented displaced trapezoidal winding produces Lorentz forces in two orthogonal directions on a permanent magnet rotor. This paper presents a unique collection of trapezoidal windings in a spherical geometry to provide active control of all 6 degrees of freedom. Equations for force and torque generation are presented, and a “decoupling� control scheme is applied to the actuator such that the 3 bearing forces and 3 control torques are decoupled and independent. The construction of a prototype is also discussed and experimental results are presented with good agreement with the theory.
BibTeX:
@inproceedings{ISMB10_23,
  author = {Lyndon Scott Stephens and David J. Carroll},
  title = {Spherical Actuation Using the Displaced Trapezoidal Winding },
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_23.pdf}
}
2006 Lembke, T.A. Understanding Electrodynamic Dampers Proceedings of ISMB10  
Abstract: This paper presents general analytical tools to predict the damping and stiffness coefficients of electrodynamic dampers. Special attention will be drawn to the different cases when the conductor is either rotating or non-rotating.
BibTeX:
@inproceedings{ISMB10_24,
  author = {Torbjörn A. Lembke },
  title = {Understanding Electrodynamic Dampers},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_24.pdf}
}
2006 Lascher, A., Umanov, M., Frishman, E. and Prishedko, H. Determination of electrodynamic and aerodynamic resistance for maglev train with an electrodynamic suspesion system Proceedings of ISMB10  
Abstract: Now development of Maglev transport has reached its practical application. Therefore, one of the most important question is determination of the area of effective application of Maglev transport systems. Resistance forces acting on the train largely determine its is calculation of these forces technical and economic parameters. The main task of this work.
BibTeX:
@inproceedings{ISMB10_25,
  author = {Arkadij Lascher and Mark Umanov and Evgeni Frishman and Helen Prishedko},
  title = {Determination of electrodynamic and aerodynamic resistance for maglev train with an electrodynamic suspesion system},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_25.pdf}
}
2006 Jugo, J., Lizarraga, I. and Arredondo, I. Nonlinear modelling and analysis of an AMB system in the harmonic domain Proceedings of ISMB10  
Abstract: In this work, the nonlinear modelling and analy-sis of an AMB system, based on the MBC500 Rotor Dynamics from Launchpoint Technologies, is presented. This approach is based on the harmonic domain linearization of the AMB system around a nonlinear stationary solution, under different rotating speeds. The nonlinear nature of the response appears at high speeds, due to the large oscillations introduced by the shaft unbalance. Using the presented methodology, low frequency gain loss is detected when increasing the rotating speed. This phenomenon causes the instability of the system, leading to destructive crashes.
BibTeX:
@inproceedings{ISMB10_26,
  author = {J. Jugo and I. Lizarraga and I. Arredondo},
  title = {Nonlinear modelling and analysis of an AMB system in the harmonic domain},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_26.pdf}
}
2006 Zhu, H., Chen, H., Xie, Z. and Zhou, Y. Configuration and Control for AC-DC Three Degrees of Freedom Hybrid Magnetic Bearings Proceedings of ISMB10  
Abstract: In this paper, an innovated AC-DC 3 degrees of freedom hybrid magnetic bearing is proposed, which is driven by a DC amplifier in axial direction and a 3-phase power converter in radial directions respectively, and the axial and radial bias magnetic fluxes are provided by a common radial polarized permanent magnet ring. The principle of producing magnetic suspension forces is introduced. By using equivalent magnetic circuit method, the calculation formulas of magnetic suspension forces and the mathematics models of the system are deduced. Nonlinearities of suspension forces and cross coupling between different degrees of freedom are studied further by calculating the suspension forces at different displacements and control currents to validate the feasibility of the mathematics models. Then based on the mathematics models of the bearing, a digital control method of this novel bearing is designed. The theory analysis and test results have shown that this magnetic bearing incorporates the merits of 3-phase AC drive, permanent magnet flux biased and axial-radial combined control, and reduces overall system size and has higher efficiency and lower cost.
BibTeX:
@inproceedings{ISMB10_27,
  author = {Huangqiu Zhu and Huaixiang Chen and Zhiyi Xie and Yang Zhou },
  title = {Configuration and Control for AC-DC Three Degrees of Freedom Hybrid Magnetic Bearings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_27.pdf}
}
2006 Zhou, Y., Zhu, H., Ji, J. and Liu, X. Decoupling Control for Bearingless Induction Motor with a-th Order Inverse System Theory Proceedings of ISMB10  
Abstract: A 5 degrees of freedom bearingless induction motor is a multi-variable, nonlinear and strong-coupled system. In order to achieve rotor suspension and operation steadily, it is necessary to realize dynamic decoupling control between torque force and suspension forces. In the paper, a method based on a-th order inverse system theory is used to study on dynamic decoupling control of bearingless induction motors. Firstly, the working principles of 3 degrees of freedom magnetic bearing and 2 degrees of freedom bearingless induction motor are analysed, the radial-axial force equations of 3 degrees of freedom magnetic bearing and the electromagnetic torque equation and radial force equations of the 2 degrees of freedom bearingless induction motor are given, and then the state equations of the 5 degrees of freedom bearingless induction motor are set up. Secondly, feasibility of decoupling control based on dynamic inverse theory for bearingless induction motor is discussed in detail, and the dynamic feedback linearization method is used to decouple and linearize the system. Finally, linear control system techniques are applied to these linearization subsystems to synthesize and simulate. The simulation results have shown that this kind of control strategy can realize dynamic decoupling control between torque force and suspension forces of the 5 degrees of freedom bearingless induction motor, and the control system has good dynamic and static performance.
BibTeX:
@inproceedings{ISMB10_28,
  author = {Yang Zhou and Huangqiu Zhu and Jinghua Ji and Xianxing Liu},
  title = {Decoupling Control for Bearingless Induction Motor with a-th Order Inverse System Theory},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_28.pdf}
}
2006 Pilat, A. PD control strategy for 3 coils AMB Proceedings of ISMB10  
Abstract: This paper presents the local PD control strategy for radial Active Magnetic Bearing (AMB) designed with three electromagnets. It is the minimal configuration of actuators that allows to levitate the rotor in the electromagnetic field. The configuration of the laboratory test-rig, hardware components of the control system and description of developed algorithm is presented. Rapid prototyping environments with ability for dynamic reconfiguration that are used in the controllers design are described. The PD control algorithm as the minimal required closed loop strategy for rotor levitation is calculated and discussed to be applied in the presented control systems.
BibTeX:
@inproceedings{ISMB10_29,
  author = {Adam Pilat},
  title = {PD control strategy for 3 coils AMB},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_29.pdf}
}
2006 Ueno, S., ichi Uematsu, S., Arai, T. and Odagiri, K. Development of Lorentz-force-type Slotless Active Magnetic Bearing Proceedings of ISMB10  
Abstract: Magnetic bearings have advantages such as no friction loss, no abrasion, lubrication free operation, and so on. However they are not used widely due to their high cost and large size. In order to solve these problems, an active magnetic bearing having a simple structure with distributed windings is proposed. The rotor consists of a permanent magnet and an iron yoke, which rotate in a body. The stator consists of a 3-phase distributed winding and is installed between a permanent magnet and a back yoke of the rotor. A Lorentz-force is generated by the stator current, and the rotor position is controlled by this force. In this paper, the bearing force is analyzed theoretically, and its control method is shown. A simple experiment confirmed that the proposed AMB can be realized.
BibTeX:
@inproceedings{ISMB10_3,
  author = {Satoshi Ueno and Shin-ichi Uematsu and Takayuki Arai and Kinya Odagiri },
  title = {Development of Lorentz-force-type Slotless Active Magnetic Bearing},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_3.pdf}
}
2006 Murata, M., Tajima, H., Watanabe, T. and Seto, K. New modeling and control methods for flexible rotors with magnetic bearings toward passing through critical speeds caused by elastic modes Proceedings of ISMB10  
Abstract: This paper proposes a new modeling and control method for flexible rotors using active magnetic bearings (AMB) toward passing through many critical speeds and realizing high-speed rotation. To achieve this, it is necessary to control vibration caused by some elastic modes under acting gyroscopic effect. A suggested model “Extended Reduced Order Physical Model� enables to express motion and vibration simultaneously. Then, we present a controller that combined PID and LQ controllers applied for the model.
BibTeX:
@inproceedings{ISMB10_30,
  author = {Masaki Murata and Hiroshi Tajima and Tohru Watanabe and Kazuto Seto},
  title = {New modeling and control methods for flexible rotors with magnetic bearings toward passing through critical speeds caused by elastic modes },
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_30.pdf}
}
2006 Zhang, G., Li, S., Liu, N., Gao, G., Zhao, Z., Cheng, G. and Yu, L. Study on Nonlinear Dynamics of Rotor System Equipped with AMB Proceedings of ISMB10  
Abstract: Taking an electric miller spindle equipped with AMB as the research object, this paper have established the non-linear dynamic model of five degrees of freedom for the rotor-AMB system, and carried on the numerical solution using the principle of multi-scale method and combined with the numerical analysis method. Besides, from the nonlinear viewpoint, the dynamic characteristics of rotor-AMB system have been studied; the bifurcation and chaos phenomenon of five degrees of freedom systems have been analyzed else. The results show, in the nonlinear scope, the rotor can appear the instability in certain situations, so there exists a question to judge the stability. The partial bifurcation curves generally enter from the sub-critical bifurcation region to the supercritical bifurcation region, then return to the sub-critical bifurcation region once more; The chaos phenomenon confirmed that, the rotor system can appear the chaos phenomenon under the certain condition, when striding across the critical speeds the chaos phenomenon is quite obvious.
BibTeX:
@inproceedings{ISMB10_31,
  author = {Gang Zhang and Songsheng Li and Ning Liu and Gang Gao and Zhifeng Zhao and Gao Cheng and Lie Yu },
  title = {Study on Nonlinear Dynamics of Rotor System Equipped with AMB},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_31.pdf}
}
2006 Lepine, X.D., Hagopian, J.D. and Mahfoudh, J. Modal Control Method for Rotors Supported by Active Magnetic Bearings based on a Condensed Reduced Model Proceedings of ISMB10  
Abstract: The work presented in this paper exposes a new approach for the control of the dynamic behavior of flexible rotors for rotating machines supported by AMB. In order to perform this control, an accurate model of the structure reduced on the modes to be controlled and an accurate model of the AMB are used. An approach involving the use of a condensed reduced model is introduced. The identification approach presents the main advantage to be easy to realize, and efficient for control. An experimental identification of an accurate inverse model of the AMB is performed, as it is necessary for modal control. The results are exposed for a flexible beam, and validates the method experimentally.
BibTeX:
@inproceedings{ISMB10_32,
  author = {Xavier De Lepine and Johan Der Hagopian and Jarir Mahfoudh},
  title = {Modal Control Method for Rotors Supported by Active Magnetic Bearings based on a Condensed Reduced Model},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_32.pdf}
}
2006 Kanemitsu, Y., Yong, X.-B., Kijimoto, S. and Matsuda, K. Comparison of Stability Criteria for Rotor Levitated by Active Magnetic Bearing Proceedings of ISMB10  
Abstract: In this paper, a phase margin, a gain margin, a sensitivity function, a maximum singular value of sensitivity function matrix and a damping ratio are taken up as indices which evaluate the stability margin of a rotor levitated by active magnetic bearings. The definition of the stability margin in this research is how far away the gain margin, the phase margin and the reciprocal number of the sensitivity function are from the critical point (-1 ,j0) in a polar plot. The stability margin distance is proposed to unify above-mentioned indices. We have estimated stability of a rotor-AMB system by these five indices and investigated relations among the indices.
BibTeX:
@inproceedings{ISMB10_33,
  author = {Yoichi Kanemitsu and Xiao-Bing Yong and Shinya Kijimoto and Koichi Matsuda},
  title = {Comparison of Stability Criteria for Rotor Levitated by Active Magnetic Bearing},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_33.pdf}
}
2006 Schuhmann, T., Hofmann, W. and Werner, R. Adaptive Linear and Extended KALMAN Filter applied to AMB with Collocated Position Measuring Proceedings of ISMB10  
Abstract: In the majority of cases, magnetically levitated rotors are equipped with externally mounted position sensors, i.e. a dislocation between bearing and sensor plane occurs. The disparity between actual and measured rotor position can cause system instability due to natural oscillations of the shaft. This paper proposes a method for avoiding this problem by integrating capacitive position sensors straight into the stator laminations of a radial magnetic bearing. The stronger sensor noise originating from the proximity between bearing coils and sensors can be reduced effectively by means of a stochastical state estimator. Different types of KALMAN filters used for these purposes, both linear and extended ones, are presented in this paper. It is shown how unknown bearing parameters can be estimated by means of the filter. Concluding, a LQG controller (optimal controller combined with optimal state estimator) is presented and compared to an optimally parametrised PID controller. All methods proposed in this paper are approved by measurements.
BibTeX:
@inproceedings{ISMB10_34,
  author = {Thomas Schuhmann and Wilfried Hofmann and Ralf Werner},
  title = {Adaptive Linear and Extended KALMAN Filter applied to AMB with Collocated Position Measuring},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_34.pdf}
}
2006 Volkert, R., Radler, O., Weißenborn, E., Ströhla, T. and Zöppig, V. Position Controller with Hysteresis Compensation for Magnetic Bearings Proceedings of ISMB10  
Abstract: This paper deals with the Jiles-Atherton model for hysteresis effects and its inversion as well as its extension for the reproduction of force-current hysteresis loops. An identification procedure for the model parameters is presented for a given solenoid actuator. A simplified hysteresis compensation algorithm was implemented on a 16-bit Digital Signal Controller. The real-time hysteresis compensation quality both for constant and variable air gap lengths was first investigated by means of an open-loop force controller for a proportional solenoid. Finally a closed-loop position controller with hysteresis compensation for an electromagnet, which is part of a magnetic bearing system, is presented. Experimental results gained at the test rigs are shown and evaluated.
BibTeX:
@inproceedings{ISMB10_35,
  author = {Ralf Volkert and Oliver Radler and Erik Weißenborn and Tom Ströhla and Veit Zöppig},
  title = {Position Controller with Hysteresis Compensation for Magnetic Bearings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_35.pdf}
}
2006 Eckhardt, S. and Rudolph, J. Trajectory Tracking for a Magnetically Levitated Shaft with Three-Phase AMBs in Y -Connection Proceedings of ISMB10  
Abstract: High precision tool path tracking with magnetically supported spindles is considered. If radial bearings with three phases in Y -connection are used standard commercial power electronics can be employed. However, only two independent currents are available then. It is shown how this problem can be overcome. Experimental results show that the tracking precision obtained with Y-connected coils is similar to the one obtained with three independent coils.
BibTeX:
@inproceedings{ISMB10_36,
  author = {St. Eckhardt and J. Rudolph},
  title = {Trajectory Tracking for a Magnetically Levitated Shaft with Three-Phase AMBs in Y -Connection},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_36.pdf}
}
2006 Klaucke, C., Eckhardt, S. and Rudolph, J. Modeling and Control of an Axial Bearing Generating Forces and Torques Proceedings of ISMB10  
Abstract: A new type of active axial magnetic bearing is considered which is capable of generating forces and torques. A network approach is used for modeling of the position dependent current-force/torque-relation. The bearing is used for positioning with a flatness-based position controller. Results from model validation and position control experiments are presented.
BibTeX:
@inproceedings{ISMB10_37,
  author = {C. Klaucke and St. Eckhardt and J. Rudolph},
  title = {Modeling and Control of an Axial Bearing Generating Forces and Torques},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_37.pdf}
}
2006 Abulrub, A.-H.G., Sahinkaya, M.N., Keogh, P.S. and Burrows, C.R. Experiments on ROLAC to Recover Rotor Position Following Contact Proceedings of ISMB10  
Abstract: There is growing interest in magnetic bearing applications because of their advantages for contactless support, high-speed operation, vibration control, condition monitoring and fault diagnostics. However, they have limited force capacity and have to incorporate retainer bearings to protect the laminations when vibration levels reach the clearance level. Retainer bearings can take a relatively small number of rotor drops followed by machine shutdown. There are many potential applications where transient events or sudden changes in operating conditions could drive the rotor into contact with retainer bearings. These include land, sea and air transport applications, which are exposed to external inputs and disturbances, and system shut down is not acceptable. This paper describes the application of a Recursive Open Loop Adaptive Controller (ROLAC), an adaptive and fast acting controller, to prevent contact between a flexible rotor and retainer bearing. If however contact does occur, then the control action will minimize the damage and recover the rotor position without the need to shut down the system. It is assumed that the magnetic bearings are fully operational and contact is due to external disturbances such as sudden un-balance, base excitation, blade loss or damage. Experimental results are presented to demonstrate the effectiveness of the control algorithm.
BibTeX:
@inproceedings{ISMB10_38,
  author = {Abdul-Hadi G. Abulrub and M. Necip Sahinkaya and Patrick S. Keogh and Clifford R. Burrows},
  title = {Experiments on ROLAC to Recover Rotor Position Following Contact},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_38.pdf}
}
2006 Chen, S.-L. Smooth Stabilizing Controllers for a 3-Pole Active Magnetic Bearing System Proceedings of ISMB10  
Abstract: In this study, a class of smooth controllers is proposed for the stabilization of a 3-pole active magnetic bearing(AMB) system. The 3-pole AMB systemis strongly nonlinear and non-affine. Conventional controllers are non smooth and complicated, which is difficult for implementation and further study. The proposed smooth controllers are designed utilizing a linear transformation on the system inputs (coil currents). Asa result, simple smooth controllers, such as quadratic state feedback controller, can be obtained. The domain of attraction of theorigin under the smooth controller is estimated. The proposed smooth controller is verified through both numerical and experimental results.
BibTeX:
@inproceedings{ISMB10_39,
  author = {Shyh-Leh Chen},
  title = {Smooth Stabilizing Controllers for a 3-Pole Active Magnetic Bearing System},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_39.pdf}
}
2006 Zhao, L., Li, H., Gu, H., Yu, S. and Zhao, H. Investigations of an AMBs Flexible Rotor for Pass through Two Bending Mode Frequencies Proceedings of ISMB10  
Abstract: No abstract available, please see full paper.
BibTeX:
@inproceedings{ISMB10_4,
  author = {Lei Zhao and Hongwei Li and Huidong Gu and Suyuan Yu and Hongbin Zhao},
  title = {Investigations of an AMBs Flexible Rotor for Pass through Two Bending Mode Frequencies},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_4.pdf}
}
2006 Seto, H., Namerikawa, T. and Fujita, M. Experimental Evaluation on Hinf DIA Control of Magnetic Bearings with Rotor Unbalance Proceedings of ISMB10  
Abstract: This paper deals with an experimental evaluation on Hinf DIA control of magnetic bearings with rotor unbalance. Hinf control problem which treats a mixed Dis-turbance and an Initial state uncertainty Attenuation (DIA) control is expected to provide a good transient property, and we confirmed that DIA control has a good rotational performance by some experiments. In this paper, we propose a modified control system design of H8 DIA control in order to consider the periodic disturbance for the magnetic bearings. In fact, we get a controller taken a peak at specified frequency by adding a frequency weighting function in generalized plant. Experimental results show that the proposed robust control approach is effective for improving rotational performance.
BibTeX:
@inproceedings{ISMB10_40,
  author = {Hiroki Seto and Toru Namerikawa and Masayuki Fujita},
  title = {Experimental Evaluation on Hinf DIA Control of Magnetic Bearings with Rotor Unbalance},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_40.pdf}
}
2006 Zhou, J., Xu, L.X., Chen, P.H., Chen, P.L., Wang, Z.J. and Zhang, Y.J. The Control of Sheet Motion in a Hot-Dip Galvanizing Line by Electromagnetic Actuator Proceedings of ISMB10  
Abstract: Control of steel sheet shape and vibration at the air knives can increase the quality, save zinc and reduce costs. In this paper, an electromagnetic actuator set is designed toevaluate the feasibility of using active magnetic levitation technology to control vibration of the steel sheet at the air knives. Electromagnetic actuators and eddy-current position sensors are used. Because there are welding lines on the steel sheet causing the unsmooth thickness of steel sheet, multi sensor technologyis adopted to make the performance calculation resultreflect the steel sheet’s real status. For the proper sensor placement, the modal analysis of the steel strip is applied. In addition, the location of the electromagnetic actuator is designed according to the principle of “equal rigidity�. So the control parameters used in laboratory can be referenced to that of the workplace. Then PID controller is used to control the sheet motion. In order to get enough forcesto control vibration, cross-section within the magnetic loop is increased, and one kind of new material with more saturation flux is selected. Through experimental verification and galvanizing line test, the set can stabilize the sheet motion greatly, improve the galvanizing quality and save zinc.
BibTeX:
@inproceedings{ISMB10_41,
  author = {Jin Zhou and Long Xiang Xu and Pu Hui Chen and Pei Lin Chen and Ze Ji Wang and Yong Jie Zhang },
  title = {The Control of Sheet Motion in a Hot-Dip Galvanizing Line by Electromagnetic Actuator },
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_41.pdf}
}
2006 Liu, S. and Mi, C. Coupled Electro-Thermal Modeling of Magnetic Bearing Systems Proceedings of ISMB10  
Abstract: This paper presents coupled electromagnetic and thermal modelling of active magnetic bearing systems. In magnetic bearing systems, the electric, magnetic, eddy current and thermal processes are intrinsically coupled. There are two major sources of heat generated in magnetic bearing: the heat generated by the DC current in the excitation coils and the heat generated by the eddy current in the high speed rotating parts. The eddy current is not uniformly distributed in the rotor and thrust bearing. In this paper, the magnetic filed is first modelled using 2D/3D finite element analysis (FEA). The eddy current information obtained in FEA is then transferred to thermal FEA model to perform thermal analysis. Hot spots can be identified in this procedure. By using Ansoft’s Electromagnetic package, the 2D/3D FEA is coupled with thermal FEA through e-Physics. Data can be automatically linked and exchanged between the magnetic and thermal models. The experiment data on a test platform validated the proposed model.
BibTeX:
@inproceedings{ISMB10_42,
  author = {Shuqin Liu and Chris Mi},
  title = {Coupled Electro-Thermal Modeling of Magnetic Bearing Systems },
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_42.pdf}
}
2006 Glauser, M. and Sanadgol, D. Automatic Initial Levitation with Active Magnetic Bearings Proceedings of ISMB10  
Abstract: Active magnetic bearings (AMBs) require a feedback controller for stable operation. This paper describes a procedure which allows for fully automated initial levitation with no knowledge about the AMB system. Combined with some adaptive or self-tuning techniques, bearings could be setup automatically with minimal human interaction, without calibration or tuning. Based on the ideal and linearized model of a single mass one degree of freedom levitated body, the criterion for a stable suspension is reviewed. A step-by-step description outlines how the needed parameters are found which lead to a stabilizing controller. A more general, hybrid model including sensor and amplifier dynamics as well as a discrete-time PID controller is used to compare the regions of stabilizing control parameters to the ideal case. The presentation of experimental data and a discussion conclude this paper.
BibTeX:
@inproceedings{ISMB10_43,
  author = {Matthias Glauser and Dorsa Sanadgol},
  title = {Automatic Initial Levitation with Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_43.pdf}
}
2006 Li, G., Lin, Z. and Allaire, P.E. Uncertainty Classification for Rotor-AMB Systems Proceedings of ISMB10  
Abstract: In this paper, we adopt the gap metric tool to analyze uncertainty propagation in rotor-AMB systems. Of special interest is the effect of open loop plant uncertainties on the closed-loop stability. The results indicate that robustness property under general feedback varies with different sources of uncertainty, i.e., some uncertainties can be easily sup-pressed by any stabilizing controller, while other uncertainties can be amplified. As a result, uncertainty can be classified according to its effect on the closed-loop robustness. From design and analysis perspective, some uncertainties can be effectively approximated or even neglected while others must be accurately modeled, and addressed explicitly in the design and analysis.
BibTeX:
@inproceedings{ISMB10_44,
  author = {Guoxin Li and Zongli Lin and Paul E. Allaire},
  title = {Uncertainty Classification for Rotor-AMB Systems},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_44.pdf}
}
2006 Li, G., Maslen, E.H. and Allaire, P.E. A Note on ISO AMB Stability Margin Proceedings of ISMB10  
Abstract: Stability is a primary robustness requirement. The stability margin is therefore a measure of the amount of system deviation from some nominal, stable configuration that can be tolerated before the system becomes unstable. The notion of ‘system deviation’ can imply many forms and mechanisms: engineers must, perforce, focus on those most likely to afflict a given system in order to obtain a meaningful assessment of relative stability. This note discusses the stability margins of rotor-AMB sys-tems. Particular attention is focused on the output sensitivity, whose peak amplitude is a common measure of sensitivity and is adopted by the new ISO standards for AMB systems. One objective is to illustrate that many common sources of instability in rotordynamic systems may be completely missed by this measure and, further, that controller design targeting reduction in output sensitivity may, in fact, lead to very poor robustness to these mechanisms. Several examples are developed to show that, while limiting the sensitivity peak is a necessary condition for rotor-AMB system stability, it may not be sufficient to ensure commercially viable robustness to common destabilizing mechanisms such as aerodynamic cross-coupling or hysteretic damping in the rotor. The primary observation is that, if the AMB is the destabilizing mechanism, then the output sensitivity will reveal it, but if the destabilizing mechanism is endemic to the rotor and the relevant feedback is not collocated with the AMB connectivity, then the output sensitivity may not assess its effect.
BibTeX:
@inproceedings{ISMB10_45,
  author = {Guoxin Li and Eric H. Maslen and Paul E. Allaire},
  title = {A Note on ISO AMB Stability Margin},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_45.pdf}
}
2006 van West, E., Yamamoto, A. and Higuchi, T. Intrinsic Placing Behavior in Zero-Power Controlled Magnetic Levitation Object Handling Proceedings of ISMB10  
Abstract: This paper introduces an aspect of Zero-Power magnetic levitation control, in which the levitated object is released or placed in a natural way without any external control commands. This intrinsic placing behavior is a result of the characteristic control feature that the coil current is actively controlled to zero instead of controlling the air gap, which is the case in conventional control strategies. The principle of this placing behavior will be explained and analyzed in this paper. A guideline to tune the controller settings to achieve this placing behavior is given and it will be supported by experiments.
BibTeX:
@inproceedings{ISMB10_46,
  author = {Ewoud van West and Akio Yamamoto and Toshiro Higuchi},
  title = {Intrinsic Placing Behavior in Zero-Power Controlled Magnetic Levitation Object Handling},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_46.pdf}
}
2006 Wei, T. and Fang, J. Notch Filter Design Based on Two-Frequency Bode Diagram for Elastic Vibration Depression of Magnetically Suspended High-Speed Rotor Proceedings of ISMB10  
Abstract: In control moment gyroscope (CMG) based on magnetically suspended rotor (MSCMG), owing to wide controller bandwidth required by nutation stability at high rotational speed, bending mode between disk and axis of rotor with I-shaped configuration becomes unstable and tends to self-exciting vibration within the range of rotor speed. This elastic vibration can be depressed through adopting notch filter (NF) in original controller of active magnetic bearing (AMB), but NF design is still an issue since high-speed flat rotor features strong gyroscopic effect and coupling radial motions. By introducing complex representation, four DOFs (degrees of freedom) of dynamic model of magnetically suspend rotor considering unstable first-order bending mode is converted into single variable form without changing poles and stability. An illustrative and robust method of two-frequency Bode diagram is proposed to analyze elastic mode stability. Correction angle requirements of bending mode at various rotor speeds are summarized and parameters including NF grade, center frequency and pole damp are designed optimally. Employing the optimized notch filter, elastic vibration amplitude of statically suspended rotor of MSCMG was attenuated by -50.0dB comparing to original and the rotor is robustly stable within the entire speed range up to 20000r/min.
BibTeX:
@inproceedings{ISMB10_47,
  author = {Tong Wei and Jiancheng Fang },
  title = {Notch Filter Design Based on Two-Frequency Bode Diagram for Elastic Vibration Depression of Magnetically Suspended High-Speed Rotor},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_47.pdf}
}
2006 Zhu, L., Knospe, C. and Maslen, E. A Complete Model for Solid Cylindrical Magnetic Actuators Proceedings of ISMB10  
Abstract: This paper presents a complete model for solid cylindrical magnetic actuators. The half-order model shows the eddy current effects on both the current stiffness and the displacement stiffness. Experiments conducted demonstrate the accuracy of the model.
BibTeX:
@inproceedings{ISMB10_48,
  author = {Lei Zhu and Carl Knospe and Eric Maslen},
  title = {A Complete Model for Solid Cylindrical Magnetic Actuators},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_48.pdf}
}
2006 de Paiva, J.A., Ferreira, J.M.S., Salazar, A.O. and Maitelli, A.L. Vectorial Speed Control using a Flux Estimator for Bearingless Machines with Divided Windings Proceedings of ISMB10  
Abstract: This work describes the Vectorial Speed Control System of a triphasic bearingless induction machine with divided windings of 1.1 kW. The control strategy used in this system is the quadrature vectorial control. To implement the control algorithm, was chosen the rotor flux referential, which is being estimated through the stator winding currents and the rotor speed. The vectorial speed controller operates in synchronism with the radial positioning controller, but these controllers should work with low mutual influence. The control system is being implemented in a 16 bits DSP (Digital Signal Processor), which operates at 40 MHz. The algorithm was developed in the ANSI C language.
BibTeX:
@inproceedings{ISMB10_49,
  author = {José Alvaro de Paiva and Jossana M. S. Ferreira and Andrés O. Salazar and André L. Maitelli},
  title = {Vectorial Speed Control using a Flux Estimator for Bearingless Machines with Divided Windings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_49.pdf}
}
2006 Ito, M., Fujiwaraand, H. and Matsushita, O. Rotational Test of Flexible Rotor Supported by Active Magnetic Bearings (Passing the 3rd Bending Critical Speed) Proceedings of ISMB10  
Abstract: In industrial rotational machinery, it has been required that a long span and a high-speed rotor are designed in order to improve efficiency and reduce costs. In concerning many flexible rotors, the 1st bending critical speed and the 2nd bending critical speed have been passed, but never the 3rd critical speed. In this study a flexible rotor having the 3rd bending critical speed within the rated speed was designed, and was tested to pass the 3rd bending critical speed, owing to fine tuning of Active Magnetic Bearing controller and accurate balancing method.
BibTeX:
@inproceedings{ISMB10_5,
  author = {Makoto Ito and Hiroyuki Fujiwaraand and Osami Matsushita },
  title = {Rotational Test of Flexible Rotor Supported by Active Magnetic Bearings (Passing the 3rd Bending Critical Speed)},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_5.pdf}
}
2006 Kawanishi, M. and Ukibune, M. Unfalsified PID Controller Design using Support Vector Machine with Gap Metric and its Application Proceedings of ISMB10  
Abstract: In this paper, we propose a data-based PID controller design method using unfalsified control technique with Support Vector Machine (SVM) and gap metric. SVM and gap metric are utilized for adjusting the weighting function of extended L2 gain criterion. The effectiveness of the proposed method is evaluated by experiments on a magnetic levitation system and an active magnetic bearing system.
BibTeX:
@inproceedings{ISMB10_50,
  author = {Michihiro Kawanishi and Masanori Ukibune},
  title = {Unfalsified PID Controller Design using Support Vector Machine with Gap Metric and its Application},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_50.pdf}
}
2006 Mizuno, T., Ishino, Y. and Takasaki, M. Nonlinear Compensation of Zero Power Magnetic Suspension for High-Performance Vibration Isolation Systems Proceedings of ISMB10  
Abstract: The treated vibration isolation system uses zero-power magnetic suspension for realizing negative stiffness and combines it with a spring that has positive stiffness (positive spring). Infinite stiffness against direct disturbance is achieved by setting the amplitude of negative stiffness to equal the positive stiffness. One of the problems of this system is that the amplitude of negative stiffness varies from the nominal value when disturabance force is applied to the isolation table. This paper presents two approaches to overcoming this problem. One is to apply a nonlinear feedback control to zero-power magnetic suspension. The other is to use a magnetic spring as a positive spring. The carried out experiment demonstrated the efficacy of both the methods.
BibTeX:
@inproceedings{ISMB10_51,
  author = {Takeshi Mizuno and Yuji Ishino and Masaya Takasaki},
  title = {Nonlinear Compensation of Zero Power Magnetic Suspension for High-Performance Vibration Isolation Systems},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_51.pdf}
}
2006 Laro, D., Porck, T., Spronck, J., van Eijk, J. and Lebedev, A. Control of a magnetically levitated slider with nm-precision Proceedings of ISMB10  
Abstract: Due to increasing demand in accuracy, the semi-conductor and optical disc mastering industry are looking for nanometer resolution vacuum compatible positioning systems. Magnetic bearings are ideally suited for this purpose, because here is there is no need for lubrication. The IU-module is a modular two degree of freedom mag-netic actuator for suspension and propulsion. The uniqueness of this actuator lies in the moving iron principle in which only iron is moving and there are no wires going to the moving body . With three IU-modules a six degree of freedom linear slider is constructed. The specifications for the slider are taken from the optical disc mastering industry , where the resolution of a single nanometer is required. To achieve nm-resolution close synergy between mechanical construction and controller design is needed. This paper shows the successful realization and controller implementation of a sub nanometer positioning slider system using the IU-modules.
BibTeX:
@inproceedings{ISMB10_52,
  author = {D. Laro and T. Porck and J. Spronck and J. van Eijk and A. Lebedev},
  title = {Control of a magnetically levitated slider with nm-precision},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_52.pdf}
}
2006 Ren, Y. and Nonami, K. Novel Robust and Adaptive Vibration Control for Active Magnetic Bearing System Proceedings of ISMB10  
Abstract: In this paper, a novel adaptive vibration control algorithm is proposed by introducing a parameter K. The asymptotic stable condition of this algorithm is mathematically derived. In the case of stationary disturbance, the algorithm is an unbalance vibration control for K=0, while for K=1, it becomes an adaptive vibration control with consumed current control. With a non-zero K, the present control algorithm is suitable for non-stationary disturbance. To validate the applicability of the present control algorithm, a series of experiments are carried out under stationary and non-stationary disturbance conditions with K ranging from 0 to 1. Our results indicate that it is possible to find an appropriate value for K to realize a relatively optimal control of both vibration and consumed current simultaneously.
BibTeX:
@inproceedings{ISMB10_53,
  author = {Yunheng Ren and Kenzo Nonami},
  title = {Novel Robust and Adaptive Vibration Control for Active Magnetic Bearing System},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_53.pdf}
}
2006 Zhang, Y. and Kobayashi, N. Control for Passing Through Critical Speeds of an Energy Storage Flywheel System by Bias Current Control Proceedings of ISMB10  
Abstract: In this paper, we address a new method of switching the critical speed by control the bias current of magnetic bearing. The bias is changeable in the sense that is a function of the rotational speed, and varies on-line in a manner that the critical speed of the rotor is controlled far away from the rotational speed of the rotor. The total stiffness of system is switched with the additional stiffness, the critical speed is switched also. In order to demonstrate the validity of the proposed method, the method is applied to a 10MWh class energy storage flywheel system to realize the control of passing through critical speed in the range of control. A simulation study illustrates the performance of the proposed bias current control method is validity for control of passing through the critical of magnetic bearing systems.
BibTeX:
@inproceedings{ISMB10_54,
  author = {Yajun Zhang and Nobuyuki Kobayashi},
  title = {Control for Passing Through Critical Speeds of an Energy Storage Flywheel System by Bias Current Control},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_54.pdf}
}
2006 Kuwata, G., Sugitani, N. and Saito, O. Development of Low Loss Active Magnetic Bearing for the Flywheel UPS Proceedings of ISMB10  
Abstract: The flywheel for the uninterruptive power supply (UPS) is required to be lower mechanical loss during high-speed rotation. We developed low loss active magnetic bearing (AMB), and applied it to the prototype of the flywheel UPS. As a result, the AMB could support up to rated rotational speed at maximum load, and measured mechanicalloss was very low. In this paper, we mentioned the design, analysis and the results of rotating test.
BibTeX:
@inproceedings{ISMB10_55,
  author = {Gen Kuwata and Noriyasu Sugitani and Osamu Saito},
  title = {Development of Low Loss Active Magnetic Bearing for the Flywheel UPS},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_55.pdf}
}
2006 Bangcheng, H. and Jiancheng, F. Design of Magnetic Bearing Reaction Wheel for High Precision Attitude Control of Spacecraft Proceedings of ISMB10  
Abstract: In this paper, a kind of 5 degree-of-freedom magnetically suspended reaction flywheel with outer rotor is designed for high-precise stabilization of spacecraft attitude, the rotor velocity is -5000rpm to 5000rpm, its angular momentum is 50Nms. The main structure of this system is given, the rotor is supported by radial active and thrust active magnetic bearings with permanent magnet, a kind of integrated eddy- current sensor for detecting radial and axial displacement of wheel rotor is designed. And the optimization design method of rotor is presented to satisfy the require of strength safety coefficient and first elasticity resonance frequency simultaneously etc. by the software of multidisciplinary design optimization (iSIGHT) and Finite element analysis software (ANSYS).
BibTeX:
@inproceedings{ISMB10_56,
  author = {Han Bangcheng and Fang Jiancheng},
  title = {Design of Magnetic Bearing Reaction Wheel for High Precision Attitude Control of Spacecraft},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_56.pdf}
}
2006 Filatov, A., McMullen, P., Davey, K. and Thompson, R. Flywheel Energy Storage System with Homopolar Electrodynamic Magnetic Bearing Proceedings of ISMB10  
Abstract: The goal of this research was to evaluate the potential of homopolar electrodynamic magnetic bearings for flywheel energy storage systems (FESSs). The primary target was a FESS for Low Earth Orbit (LEO) satellites, however, the design can also be easily adapted for Earth-based applications. The main advantages of Homopolar Electrodynamic Bearings compared to more conventional Active Magnetic Bearings (AMB) are simplicity and very low power ratings of their electronics. These result in higher system reliability, which is a critical factor for space applications. For commercial applications, these technologies may equally be found very attractive due to a potentially lower cost when compared to AMB.
BibTeX:
@inproceedings{ISMB10_57,
  author = {Alexei Filatov and Patrick McMullen and Kent Davey and Richard Thompson},
  title = {Flywheel Energy Storage System with Homopolar Electrodynamic Magnetic Bearing},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_57.pdf}
}
2006 Zhang, Y. and Kobayashi, N. Model and Control of Energy Storage Flywheel System Used in an Electric Vehicle Proceedings of ISMB10  
Abstract: This paper is a report of the research of an energy storage flywheel system with a flexible rotor used for an electric vehicle. After introduce the energy storage flywheel system, the parameters of the rotor and the flywheel are decided by the vibration analysis of ANSYS. Based on the vibration analysis results, the model of the rotor and the flywheel is designed. In order to reduce the noise from ground, a moveable foundation is designed. Then robust controllers of the rotor system and the foundation are constructed respectively to decrease the noise from the ground. Form the simulation results, we verified that the proposed model and the controller are effective for the energy storage flywheel system used in an electric vehicle.
BibTeX:
@inproceedings{ISMB10_58,
  author = {Yajun Zhang and Nobuyuki Kobayashi},
  title = {Model and Control of Energy Storage Flywheel System Used in an Electric Vehicle},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_58.pdf}
}
2006 Burgos, D.C., Sirbu, G.M., Porres, F.M., Landajuela, J.V. and Agorreta, L.F. PD Control and Sliding Mode Control Using Feedback Linearization for 3-Pole Radial Magnetic Bearings of an Energy Storage Flywheel Proceedings of ISMB10  
Abstract: In this paper a model and two control strategies are developed for the two radial active magnetic bearings (AMB) of an energy storage flywheel. The model is detailed, taking account of all significant phenomena in system. A linear control (proportional derivative control – PD control) and a nonlinear control (sliding mode control – SM control) based on the feedback linearization of the nonlinear magnetic bearing system are developed in order to find the best control for this system.
BibTeX:
@inproceedings{ISMB10_59,
  author = {David Cantero Burgos and Gabriel Mihai Sirbu and Fernando Martin Porres and Javier Vadillo Landajuela and Luis Fontan Agorreta},
  title = {PD Control and Sliding Mode Control Using Feedback Linearization for 3-Pole Radial Magnetic Bearings of an Energy Storage Flywheel},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_59.pdf}
}
2006 Ghodsi, M., Ueno, T., Higuchi, T., Teshimab, H. and Hiranob, H. Shape Dependency in Levitation System Using HTS and Soft Magnetic Material Proceedings of ISMB10  
Abstract: It is well known that a ferromagnetic material can be levitated by a field cooled superconductor. This paper presents a new method to model the pinning effect by using a Finite Element Method (FEM). Being comparedwith the experimental results the validity of the presented method is verified. Furthermore, the effect of pole shape on the stiffness of the levitation system is investigated. The relationship between the attractive force and the air gap was numerically analyzed and experimentally measured at both, room temperature (RT) and superconductivity state (77 K). Results obtained from FEM modeling show a good agreement with experimental results. It was found that the stiffness of the system becomes almost double (6 N/mm) when the ring pole is used instead of cylindrical pole with the same surface area.
BibTeX:
@inproceedings{ISMB10_6,
  author = {Mojtaba Ghodsi and Toshiyuki Ueno and Toshiro Higuchi and Hidekazu Teshimab and Hosei Hiranob },
  title = {Shape Dependency in Levitation System Using HTS and Soft Magnetic Material},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_6.pdf}
}
2006 McMullen, P., Vuong, V. and Hawkins, L. Flywheel Energy Storage System with AMBs and Hybrid Backup Bearings Proceedings of ISMB10  
Abstract: An AMB supported, 140 kW energy storage flywheel has been developed to provide 15 seconds of ride-through power and UPS service in conjunction with a diesel generator set. The flywheel, which operates ina vacuum, is supported by AMB to minimize bearing losses, and has a high power motor/generator coupled to an efficient power conversion module. As part of the flywheel module a backup bearing system to the AMB was developed and tested.
BibTeX:
@inproceedings{ISMB10_60,
  author = {Patrick McMullen and Vinh Vuong and Lawrence Hawkins},
  title = {Flywheel Energy Storage System with AMBs and Hybrid Backup Bearings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_60.pdf}
}
2006 Ren, M., Nonami, K., Kubo, A. and Kameno, H. Zero Bias Hinf Control of Flexible Rotor Magnetic Bearing Flywheel System with Gyroscopic Effect Using Singular Value Decomposition Proceedings of ISMB10  
Abstract: This investigation deals with a small flywheel energy storage rotor supported by magnetic bearing system. A flexible model based on finite-element method is derived. Thereafter, we proposed making a mode separation using singular value decomposition method when the gyroscopic matrix is considered in the equation of motion. Further, the reliability of reduced–order FEM model is verified and the five Hinf controllers are designed to guarantee the whole stability up to 200Hz. The effectiveness of the reduced-order flexible model and the stability of the closed-loop system are verified by simulations.
BibTeX:
@inproceedings{ISMB10_61,
  author = {Ming Ren and Kenzo Nonami and Atsushi Kubo and Hironori Kameno },
  title = {Zero Bias Hinf Control of Flexible Rotor Magnetic Bearing Flywheel System with Gyroscopic Effect Using Singular Value Decomposition},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_61.pdf}
}
2006 Meeker, D.C. and Maslen, E.H. Analysis and Control of a Three Pole Radial Magnetic Bearing Proceedings of ISMB10  
Abstract: This work presents a new method of formulating the current to force relationship for a three-pole radial magnetic bearing. This relationship is readily inverted to yield a general mapping from force to current that can be realized by a three-phase motor drive. Position dependence of the bearing forces and force slew rate limiting implications are also explored.
BibTeX:
@inproceedings{ISMB10_62,
  author = {David C. Meeker and Eric H. Maslen},
  title = {Analysis and Control of a Three Pole Radial Magnetic Bearing},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_62.pdf}
}
2006 He, H., Shi, L., Zhao, L. and Zhang, L. Identification of Active Magnetic Bearing System Based on Virtual Instruments Proceedings of ISMB10  
Abstract: The dynamics of the contact-free hovering active magnetic bearing (AMB) depends mainly on the implemented control law. The more of the whole rotor system characteristics are known, the higher quality controller is designed, and the more reliable rotating operation can be realized. In order to make the identification procedure more convenient, a new development platform based on virtual instruments was chosen to design the identification system. Experiment was done on an active magnetic bearing system after the identification system was finished. The model parameters of HTR-10GT principle AMB system were identified by the help of the designed identification system, and the amplitude-frequency curve, phase-frequency curve and transfer function of the AMB system in the working frequency-domain were achieved. The identified information not only lays foundation for analyzing the characteristics of the AMB system (such as zero-pole distribution, stability margin, stiffness and damping), but also offers a kind of analysis and experimental tool for the optimized designing of the control system.
BibTeX:
@inproceedings{ISMB10_63,
  author = {Hangyu He and Lei Shi and Lei Zhao and Liangju Zhang },
  title = {Identification of Active Magnetic Bearing System Based on Virtual Instruments},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_63.pdf}
}
2006 Kärkkäinen, A., Mikkola, A. and Sopanen, J. Transient Simulation of AMB Supported Electric Motor during Rotor Drop on Retainer Bearings Proceedings of ISMB10  
Abstract: Active magnetic bearings present a new technology which has many advantages compared to traditional bearing designs. Active magnetic bearings, however, require retainer bearings in order to prevent damages in the event of a component, power or control loop failure. In the drop-down situation the design parameters of the retainer bearings have a significant influence on the behavior of the rotor. In this study, the dynamics of an active magnetic bearings supported electric motor when the rotor is dropped on retainer bearings is studied using a multibody simulation model. The retainer bearings are modeled using a detailed ball bearing model, which accounts damping and stiffness properties, oil film and friction between races and rolling elements. The model of the magnetic bearing system contains unbalances of the rotor and stiffness and damping properties of support. In this study, a computationally efficient contact model between the rotor and the retainer bearings is proposed.
BibTeX:
@inproceedings{ISMB10_64,
  author = {Antti Kärkkäinen and and Aki Mikkola and Jussi Sopanen},
  title = {Transient Simulation of AMB Supported Electric Motor during Rotor Drop on Retainer Bearings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_64.pdf}
}
2006 Alpaugh, H.E., Nelson, F.C. and Fermental, D.W. Real Time Digital Control of an Active Magnetic Bearing using Open Source Software Proceedings of ISMB10  
Abstract: A digital control system using a real time variant of Linux is developed and implemented on a bench-top rotor suspended on active magnetic bearings. The combination of simple hardware and open source software provides a useful educational and research platform for digital control methods that is unencumbered by proprietary constraints as well as one that is more cost effective than available commercial systems. A real time operating system must ensure that specific tasks are executed at a fixed rate regardless of other system level demands. This is achieved with special purpose kernels that allow Linux to run as a low priority task within the real time operating system. Digital filters are constructed and coded in C, the native language of Linux. The controller is implemented on an off-the-shelf Pentium 3 personal computer operating in a multiple channel configuration at 10 KHz.
BibTeX:
@inproceedings{ISMB10_65,
  author = {H. E. Alpaugh and F. C. Nelson and D. W. Fermental},
  title = {Real Time Digital Control of an Active Magnetic Bearing using Open Source Software},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_65.pdf}
}
2006 Cao, X., Deng, Z., Yang, G. and Wang, X. The Mathematical Model of Bearingless Switched Reluctance Motors With Two-Phase Excitation Proceedings of ISMB10  
Abstract: In view of limitations of mathematical model only suited for the single-phase excitation mode in bearingless switched reluctance motors (BSRM), a novel mathematical model of BSRM with one or two-phase excitation is proposed. The inductance matrix is constructed based on the magnetic equivalent circuits in the two-phase excitation mode. New mathematical formulas of radial force and electromagnetic torque are derived. The operating area of BSRM can be expanded to a great extent. The capability of bearing radial force is enhanced greatly. Computer simulations with magnetic-field analytical-method verify the validity and fine characteristics of the new mathematical model. Two optimizing methods to distribute currents of two-phase windings including main windings and radial force windings for practical applications are also proposed.
BibTeX:
@inproceedings{ISMB10_66,
  author = {Xin Cao and Zhiquan Deng and Gang Yang and Xiaolin Wang },
  title = {The Mathematical Model of Bearingless Switched Reluctance Motors With Two-Phase Excitation},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_66.pdf}
}
2006 Sun, Y., Ho, Y.-S. and Yu, L. Magnetic Force of Radial Magnetic Bearing Considering Eddy Currents Effect Proceedings of ISMB10  
Abstract: The magnetic force of a radial magnetic bearing including the eddy current effects due to the rotation of shaft and the variation of the dynamic control current is investigated in this paper. With assumptions of moderate eddy currents developed in the rotor and stator, an approximate general form of the magnetic force is derived. The results show that the eddy current due to rotation of the rotor affects the magnitude of the static force and amplitude of the dynamic force while that induced by the dynamic control current will reduce the amplitude of the dynamic force and cause phase lag. Moreover, eddy current due to rotation results in equal decrease in the magnitude or amplitude of the static and dynamic forces. The current stiffness then derived with the dynamical force shows that the varieties of the stiffness with speed has a similar trend to that of the static one. A case study was investigated by FEM and the results agree well with the analysis. Furthermore, since the flux saturation in the eddy current regions is moderate, the nonlinear model considering flux saturation gives nearly the same results as the linear one. The result is applicable to not only solid rotor and stator but also to laminated structures.
BibTeX:
@inproceedings{ISMB10_67,
  author = {Yanhua Sun and Yick-Sing Ho and Lie Yu},
  title = {Magnetic Force of Radial Magnetic Bearing Considering Eddy Currents Effect},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_67.pdf}
}
2006 Sawicki, J.T., Maslen, E.H. and Bischof, K.R. AMB controller design for a machining spindleusing mu-synthesis Proceedings of ISMB10  
Abstract: Control of an AMB supported machining spin-dle was explored to determine the potential advantages of µ-synthesis relative to more a conventional strategy based on PID with notch filters. The spindle was manufactured by Revolve Magnetic Bearings, Inc. and adapted to permit control using a dSpace real time digital controller. This very open platform enabled introduction of arbitrary control algorithms, synthesized in MatLab(TM) . The study compares the performance of a carefully de-signed PID + notch compensator to that of aµ-synthesized controller. The main finding is thatµ-synthesis is better able to reduce tool tip compliance than is PID+notch and that this improvement was a factor of at least 2 over a wide range of frequencies for the spindle examined.
BibTeX:
@inproceedings{ISMB10_68,
  author = {Jerzy T. Sawicki and Eric H. Maslen and Kenneth R. Bischof},
  title = {AMB controller design for a machining spindleusing mu-synthesis},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_68.pdf}
}
2006 Maslen, E.H., Knospe, C.R. and Zhu, L. An enhanced dynamic model for the actuator/amplifier pair in AMB systems Proceedings of ISMB10  
Abstract: Typical models for AMB actuators consist of a static linearized mapping from displacement and current to force (f ˜-Kxx+Kii) and are augmented with actuator dynamics (bandwidth and gain) which act to correlate a command signalVc to resulting current: I(s)=Ga(s)Vc(s). In the present work, we show that this model misses a number of potentially important features, most notably the effect of amplifier bandwidth limitations on the term mapping displacement to force (Kx) and the related influence of journal motion induced back-EMF. In addition, we show how actuator eddy currents interact with the amplifier dynamics and how to model the resulting composite system.
BibTeX:
@inproceedings{ISMB10_69,
  author = {Eric H. Maslen and Carl R. Knospe and Lei Zhu},
  title = {An enhanced dynamic model for the actuator/amplifier pair in AMB systems},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_69.pdf}
}
2006 Sha, H., Xu, Y., Shi, L. and Zhao, L. A new Magnetic Baering-Rotor system Proceedings of ISMB10  
Abstract: The technology of the Active Magnetic Bearing is developed so fast that it can be utilized in many field. In order to reduce the size of the magnetic bearing to fit the artificial heart, magnetic suspended hard disk, gyroscope and etc, a new minitype Magnetic Bearing-Rotor system is successfully designed by improving the mechanical structure and control technique of the bearing. It also can suspend stably. Experiments have already proved that this design can not only effectively reduce the size of bearing but also simplify the structure of bearing.
BibTeX:
@inproceedings{ISMB10_7,
  author = {Honglei Sha and Yang Xu and Lei Shi and Lei Zhao},
  title = {A new Magnetic Baering-Rotor system },
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_7.pdf}
}
2006 Zheng, K., Liu, H. and Yu, L. Control and Dynamics of a 2-Degree Rigid Rotor - Magnetic Bearing System with Time Delay Proceedings of ISMB10  
Abstract: The introduction of digital control into AMB systems brings us not only many benefits but also the time delay in computing control output, so called computing time delay. In this paper, a 2-degree rigid rotor magnetic system is employed and the negative effect of computing time delay on this system is discussed. Then an attempt to improve control strategies on compensation for time delay is made and a state predictive module is introduced into closed-loop control system. Simulation results show the control performance degrades owning to computing time delay, even causing instability when the value of time delay exceeds the upper bound as we discussed. And via the addition of time delay compensating module, the control performance is well improved, indicating the effectiveness of the proposed method. Index Terms– time delay, stability, control.
BibTeX:
@inproceedings{ISMB10_70,
  author = {K. Zheng and H. Liu and L. Yu},
  title = {Control and Dynamics of a 2-Degree Rigid Rotor - Magnetic Bearing System with Time Delay},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_70.pdf}
}
2006 Quan, B., Yang, X., Shi, Z., Zhao, L. and Yu, S. The dissipation models of AMB and its computational methods Proceedings of ISMB10  
Abstract: Active magnetic bearing (AMB) is a kind of advanced high speed bearing, it is used to suspend rotor without contact between stator and rotor by magnetic power. At present researches on active magnetic bearing mainly focus on power amplifier and control system, but the researches on its power losses are very few. Because active magnetic bearing is turning at high speed, its power losses can not be neglected. Power losses can increase the temperature of AMB, make stator and rotor thermal deformation, have an effect on bearing’s orientation, even make stator and rotor produce distortion, and influence active magnetic bearing normaloperation. At the same time, it can reduce insulation capability of windings; shorten its life-span. So it is important to estimate the power losses to insure AMB normal operation. There are three kinds of power losses in AMB, including copper losses, iron losses and windage losses. It is necessary to research and compute the three kind of power losses. This paper investigated present researches on power dissipation of AMB, summarized three dissipation models, gave their computational methods and their application range. Copper losses can be computed by ohm law. Iron losses consist of eddy losses and hysteresis losses. Eddy losses are generally proportional to the square of frequency. Hysteresis losses are generally proportional to frequency. So hysteresis losses are very low in iron losses at high frequency and can be ignored, but it will account for the large proportion of iron losses at low frequency. And iron losses depend on the arrangement of magnetic pole, such as alternating pole (NSSN) and paired pole (NNSS). At present the analysis of iron losses are based on such assumptions as material linearity and neglect of magnetic saturation, but material nonlinearity must be token into account when AMB rotates at high speed, so actual iron losses are larger than computational results. Windage losses can be described by fluid state in air gap and corresponding empirical formula, and in high-speed motors the surface speed of the rotor is typically between 150 and 400 m/s. At this range the windage losses are proportional to the cube of the surface speed. Index Terms – active magnetic bearing; copper losses; iron losses; windage losses.
BibTeX:
@inproceedings{ISMB10_71,
  author = {Biao Quan and Xiaoyong Yang and Zhenggang Shi and Lei Zhao and Suyuan Yu},
  title = {The dissipation models of AMB and its computational methods},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_71.pdf}
}
2006 Gosiewski, Z. and Zokowski, M. Sliding Mode Control for Active Magnetic Bearings Proceedings of ISMB10  
Abstract: The paper evaluates the sliding mode control methodology as a control law for an active magneticbearing. Developments in power electronics has made it possible to implement a modern control theory to various kinds of electrical and mechanical systems. This paper describes sliding mode control of a single-axis magnetic bearing’s actuator. Sliding mode control (SMC) offers several advantages over the other control methods as follows: robustness; good dynamic response; simple implementation. Sliding mode control is a non-linear, model-based control method supported by the Lyapunov stability theory. It has been proved to be an efficient technique to provide good tracking performance, applied to non-linear systems with external disturbances. It also allows the plant model to be imprecise, for example a model that has been simplified due to difficulties in representing system dynamics. Among applications where sliding mode control has been applied successfully there are: submarines, ground vehiclesand aeroplanes.
BibTeX:
@inproceedings{ISMB10_72,
  author = {Zdzislaw Gosiewski and Mariusz Zokowski},
  title = {Sliding Mode Control for Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_72.pdf}
}
2006 Pöllänen, R., Nerg, J., Rilla, M. and Pyrhönen, O. Transient Thermal Model for Radial Active Magnetic Bearing Proceedings of ISMB10  
Abstract: A lumped-parameter thermal model capable of both static and transient analysis for a radial active magnetic bearing is presented. The determination of the electromag-netic state of the bearing using reluctance network method is proposed and the analytical calculation of four different power loss sources is discussed in details. The thermal model is tested by determing the power losses, steady state temperature distribution and transient temperature response of a prototype 8-pole magnetic bearing.
BibTeX:
@inproceedings{ISMB10_73,
  author = {Riku Pöllänen and Janne Nerg and Marko Rilla and Olli Pyrhönen},
  title = {Transient Thermal Model for Radial Active Magnetic Bearing},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_73.pdf}
}
2006 Keogh, P.S., Cade, I.S. and Sahinkaya, M.N. The Use of Wavelet Analysis for the Closed Loop Control of Vibration in Magnetic Bearing Systems Proceedings of ISMB10  
Abstract: Wavelet analysis provides a method of identify-ing localised time-frequency components within a vibratory signal. It also has direct links with digital signal processing. This paper focuses on the use of wavelet analysis within ro-tor/active magnetic bearing systems for fault detection, system identification and closed loop transient control. The closed loop controller is formulated in the wavelet coefficient domain using real-time evaluation of the wavelet transform, which involves a signal processing delay. The controller is designed to mimimise the wavelet coefficients of measured rotor vibration signals. Hence, this implies that the rotor vibration will be attenuated by the control action. Experimental results are presented to show how control in the wavelet coefficient domain is effective in attenuating transient rotor vibration arising from step synchronous input forces.
BibTeX:
@inproceedings{ISMB10_74,
  author = {Patrick S. Keogh and Iain S. Cade and M. Necip Sahinkaya},
  title = {The Use of Wavelet Analysis for the Closed Loop Control of Vibration in Magnetic Bearing Systems},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_74.pdf}
}
2006 Grochmal, T.R. and Lynch, A.F. Vibration Compensation and Precision Tracking of a Rotating Shaft by Nonlinear State Feedback Proceedings of ISMB10  
Abstract: In this paper, a nonlinear observer-based state feedback is derived to achieve precision tracking of a rotating shaft supported by active magnetic bearings (AMBs). Velocity and disturbance observers are constructed which operate in a hierarchical manner. This approach reduces the order of the design and modularizes compensation for synchronous vibration. Experimental results on a commercially available five degree-of-freedom system demonstrate accurate position tracking over the bearing air gap.
BibTeX:
@inproceedings{ISMB10_75,
  author = {Thomas R. Grochmal and Alan F. Lynch},
  title = {Vibration Compensation and Precision Tracking of a Rotating Shaft by Nonlinear State Feedback},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_75.pdf}
}
2006 Fujiwara, H., Ito, M. and Matsushita, O. Application of Tracking Solver for Active Magnetic Bearing Controller Design Proceedings of ISMB10  
Abstract: The tracking solver we propose is defined by sliding mode control theory so that the numerical time history of the solution traces exact values. If one of the initial solutions is provided, the solver calculates all solutions as parameters change from initial to final. The solver solves linear or nonlinear equations. Here we apply it to controller design based on several control design strategies, i.e., direct pole placement, optimal control, and phase adjustment. These control design methods mainly determine control feedback gain ane other parameters required for closed-loop behavior of the system. Because this solver obtains gain and parameters as the final condition is selected, control is easier to design. We effectively tuned the controller of an active magnetic bearing using this solver.
BibTeX:
@inproceedings{ISMB10_76,
  author = {Hiroyuki Fujiwara and Makoto Ito and Osami Matsushita},
  title = {Application of Tracking Solver for Active Magnetic Bearing Controller Design},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_76.pdf}
}
2006 Jastrzebski, R., Pöllänen, R., Pyrhönen, O., Kärkkäinen, A. and Sopanen, J. Modeling and Implementation of Active Magnetic Bearing Rotor System for FPGA-based Control Proceedings of ISMB10  
Abstract: This article reveals an implementation of a flexible rotor model with the nonlinear actuator for an LQ-control realization using field programmable gate arrays. The presented AMB-rotor model can be utilized both for the controller (as a state observer and nonlinearity compensator) and for the system development as a real-time plant emulator. The different variants of the LQ position control are considered in regard to the rotor model, used as a part of the observer. The model of the studied rotor was obtained using the finite element modeling, modal reduction technique and experimental analysis.
BibTeX:
@inproceedings{ISMB10_77,
  author = {Rafal Jastrzebski and Riku Pöllänen and Olli Pyrhönen and Antti Kärkkäinen and Jussi Sopanen},
  title = {Modeling and Implementation of Active Magnetic Bearing Rotor System for FPGA-based Control},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_77.pdf}
}
2006 Kluyskens, V. and Dehez, B. Induced currents in magnetic bearings: dynamical electromechanical model Proceedings of ISMB10  
Abstract: Magnetic bearings are systems where strong interactions coexist between electro-magnetic and mechanical phenomenon. This paper presents an analysis of these interac-tions and of the way they can generate a potentially unstable behaviour. An analytical model is presented considering the electromagnetic nature of the forces and the general rotating machinery aspects. The coefficients of the model are found by identification with a finite element model of the system and with experimental measurements.
BibTeX:
@inproceedings{ISMB10_78,
  author = {V. Kluyskens and B. Dehez},
  title = {Induced currents in magnetic bearings: dynamical electromechanical model},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_78.pdf}
}
2006 Jing, M.Q., Su, W.J., Liu, H. and Yu, L. Identification and Control of Control Delay for Digital Control Magnetic Bearing System Proceedings of ISMB10  
Abstract: The delay time of an active magnetic bearing (AMB) digital control system with a decentralized PID controller is measured. Numerical simulation results of time delay effects on the dynamic performance of a 2-axis controlled active magnetic bearing rotor system (AMBRS) are presented. An investigation of reducing time delay effects using a Smith predictor controller is also introduced. Experimental results show that the scale of delay time is from decades to hundreds microseconds. Furthemore, the simulation results indicate that time delay mainly affects journal center orbit, And results in the instability of the first natural mode of AMBRS. The simulation results also prove that Smith predictor is very effective in reducing time delay effects.
BibTeX:
@inproceedings{ISMB10_79,
  author = {M. Q. Jing and W. J. Su and H. Liu and L. Yu},
  title = {Identification and Control of Control Delay for Digital Control Magnetic Bearing System},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_79.pdf}
}
2006 Oka, K., Ninomiya, N., Chen, L. and Fujiwara, Y. Magnetic Suspension System with Variable Flux Path Mechanism Using Rotary Actuator Proceedings of ISMB10  
Abstract: This paper describes a novel type of magnetic suspension system with a permanent magnet and a rotary actuator. The feature of this suspension system is that a rotary actuator controls attractive force. Varying the angle of the permanent magnet driven by the actuator changes magnetic flux path in the suspension system and controls the suspension force. The merits of this suspension system are that the attractive force of this magnetic circuit can be made to be zero. Moreover this system can change the polarity of stator poles. First an outline of the suspension system will be described. Next, the principle of the suspension mechanism will be explained. To verify the feasibility of the proposed system, some basic experiments, a numerical simulation, and an experimental result will be shown.
BibTeX:
@inproceedings{ISMB10_8,
  author = {Koichi Oka and Noriaki Ninomiya and Li Chen and and Yusuke Fujiwara},
  title = {Magnetic Suspension System with Variable Flux Path Mechanism Using Rotary Actuator},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_8.pdf}
}
2006 Zhang, K., Dai, X., Zhang, X. and Jiang, X. Experiment Study on a High Speed Motor Supported by Active Magnetic Bearings Proceedings of ISMB10  
Abstract: In a high speed motor system suspended by active magnetic bearings, the bearing load capability is limited, the bias force from the motor rotor produced by permanent magnets is large compared with the bearing load capability and the influence of the residual unbalance in the rotor is obvious. So the active magnetic bearings have to work with nonlinearity conditions and high speed running is hard to be achieved. To deal with the marked nonlinearity of the active magnetic bearing system, a global linearization method is used to linearize the magnetic forces produced by active magnetic bearings. Meanwhile, controller designs are improved. A gain schedule method is used to make the rotor running stable across its rigid critical speed. Through using a zero-pole pair shaping method, the gain of the controller in the frequency domain near the running frequency of the rotor is effectively decreased and the rotor runs almost about its mass centre. The saturation of the magnetic forces of the active magnetic bearings is avoided and stable running of the motor system at high rotation speeds is achieved.
BibTeX:
@inproceedings{ISMB10_80,
  author = {Kai Zhang and Xingjian Dai and Xiaozhang Zhang and Xingjian Jiang},
  title = {Experiment Study on a High Speed Motor Supported by Active Magnetic Bearings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_80.pdf}
}
2006 Chen, H.M. and Walter, T.J. A Foil-Magnetic Thrust Bearing Using LCR Circuit Proceedings of ISMB10  
Abstract: An ac magnet based on the LCR resonance circuit shares load with a foil thrust bearing with eight pads, which supports the weight and impeller thrust load of a vertically oriented gas compressor. For the stability o f the combined beari ng, the amplitude of excit ation voltage to the LCR circuit is controlled as a function of rotor speed. To augment the low damping inherent in the ac suspension, a velocity feedback control is applied to modulate the excitation vo ltage and achieve electricdamping.
BibTeX:
@inproceedings{ISMB10_81,
  author = {H. Ming Chen and Thomas J. Walter},
  title = {A Foil-Magnetic Thrust Bearing Using LCR Circuit},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_81.pdf}
}
2006 Yang, G., Xu, Y., Wan, L., Zhao, L. and Yu, S. Preliminary Structural Design and Dynamical Analysis of Auxiliary Bearing for HTR-10GT Proceedings of ISMB10  
Abstract: The electromagnetic bearing was chosen to support the rotor of power conversion unit (PCU) and helium blower fan in 10MW high temperature gas-cooled reactor (HTR-10GT), and the auxiliary bearing was applied in the HTR-10GT as the backup protector. HTR-10GT is the second phase of the 10MW high-temperature gas-cooled testreactor (HTR-10). HTR-10 is the first module high-temperature gas-cooled test reactor in the world. It was constructed by INET at Tsinghua University of China. A direct gas cycle to replace the current steam cycle of HTR-10 was studied in the HTR-10GT. However, one implication of magnetic bearings is the requirement to provide backup support to mitigate the effects of failures or overload conditions. The auxiliary bearing is used to support the rotor when the magnetic bearing fails to work. Especially when the rotor is rotating with high speed, the magnetic bearing suddenly doesn’t support the rotor for the power off. So it is very important for the auxiliary bearing to protect the rotor system. The PCU rotor’s length is about 7 m, its weight is about 1500 kg and the rotating speed is 15000 r/min. The rotor’s length of helium blower fan is about 1.5 m, its weight is about 240 kg and the rotating speed is about 5400 r/min. The design of the auxiliary bearing is one of the challenging problems in the whole system. It is very important for HTR-10GT to make success. In this paper, the research status ofthe auxiliary bearing was summarized. A sort of preliminary scheme of auxiliary bearing structure was proposed. The falling course was analyzed. The stress of the rotor and auxiliary bearing was computed by the finite element method. MSC.Marc was selected to analyze the vibration mode and the natural frequency of the rotor. The scheme of auxiliary bearing and the analytical results offer the important theoretical base for the protector design of the HTR-10GT.
BibTeX:
@inproceedings{ISMB10_82,
  author = {Guojun Yang and Yang Xu and Li Wan and Lei Zhao and Suyuan Yu },
  title = {Preliminary Structural Design and Dynamical Analysis of Auxiliary Bearing for HTR-10GT},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_82.pdf}
}
2006 Worlitz, F. and Rottenbach, T. Determination of Forces on a Completely Activ Magnetic Suspended Coolant Pump in a Power Station Proceedings of ISMB10  
Abstract: This paper describes the retrofitting of a coolant pumpfrom conventionalbearings to activemagnetic bearings and the determination of the bearing forcesunder real operation conditionsin a power plant.
BibTeX:
@inproceedings{ISMB10_83,
  author = {Frank Worlitz and Torsten Rottenbach},
  title = {Determination of Forces on a Completely Activ Magnetic Suspended Coolant Pump in a Power Station},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_83.pdf}
}
2006 Takahashi, N., Miura, H. and Fukushima, Y. Thermally Induced Synchronous Vibration Instability in a Magnetic Bearing Supported High-speed Rotor Proceedings of ISMB10  
Abstract: This paper describes a synchronous vibration instability problem that occurred on a two-stage overhung centrifugal compressor. The authors encountered an unbalance vibration that increased spirally in a polar plot at/near the first bending critical speed. An iron loss concentration and a thermal bend by heat have been identified as the cause of the phenomenon, because the vibration stops increasing, when an unbalance force rejection control (UFRC) is applied. In order to exceed the first bending critical speed stably, an rotor unbalance measurement under UFRC and a rapid speed acceleration/deceleration are carried out. The vibration behaviours around the critical speed are simulated and verified experimentally. The stability limit that is depending on rotational speed is calculated and the most important parameter |H/P| in the calculation are determined by measurements.
BibTeX:
@inproceedings{ISMB10_84,
  author = {Naohiko Takahashi and Haruo Miura and Yasuo Fukushima},
  title = {Thermally Induced Synchronous Vibration Instability in a Magnetic Bearing Supported High-speed Rotor},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_84.pdf}
}
2006 Sandtner, J. and Bleuler, H. Passive Electrodynamic Magnetic Thrust Bearing Especially Designed for Constant Speed Applications Proceedings of ISMB10  
Abstract: Two years ago we presented a magnetic thrust bearing consisting of two stationary sets of coils located between two rotating planar repulsive Halbach arrays. We will present here a small modification of these bearings by purely passive elements, which increase the restoring stiffness by a factor of up to ten. This modification is particularly suitable for constant speed applications.
BibTeX:
@inproceedings{ISMB10_85,
  author = {Jan Sandtner and Hannes Bleuler},
  title = {Passive Electrodynamic Magnetic Thrust Bearing Especially Designed for Constant Speed Applications},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_85.pdf}
}
2006 Achkar, R., Nasr, C., Miras, J.D. and Charara, A. Neural Networks Implementation to Control An Active Magnetic Bearing Proceedings of ISMB10  
Abstract: No abstract available, please see full paper.
BibTeX:
@inproceedings{ISMB10_86,
  author = {Roger Achkar and Chaiban Nasr and Jerôme De Miras and Ali Charara},
  title = {Neural Networks Implementation to Control An Active Magnetic Bearing},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_86.pdf}
}
2006 Kasarda, M., Inman, D., Kirk, R., Quinn, D., Mani, G., Bash, T. and Stephens, L.S. A Magnetic Bearing Actuatorfor Detection of Shaft Cracks in Rotating Machinery Supported in Conventional Bearings Proceedings of ISMB10  
Abstract: This paper demonstrates experimentally the capability of an AMB actuator to detect shaft cracks during operation of a rotor that would otherwise go undetected by conventional health monitoring methods. The AMB actuator is used in a mid-span location on a rotor supported in conventional rolling element bearings, although the technique is expected to be applicable to AMB-supported rotors.
BibTeX:
@inproceedings{ISMB10_87,
  author = {M.E. Kasarda and D. Inman and R.G. Kirk and D. Quinn and G. Mani and T. Bash and L. S. Stephens},
  title = {A Magnetic Bearing Actuatorfor Detection of Shaft Cracks in Rotating Machinery Supported in Conventional Bearings},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_87.pdf}
}
2006 Ueno, T. and Higuchi, T. Combination of Magnetostrictive/ Piezoelectric Materials Composite and Electromagnet for Zero Power Levitation Proceedings of ISMB10  
Abstract: This paper presents zero-power levitation using a composite of magnetostrictive (GMM) /piezoelectric (PZT) materials. The control of the magnetic force is based on the inverse magnetostrictive effect of the GMM, by which the magnetic force can be varied with applied voltage onthe PZT. The distinctive advantage of the composite is zero power consumption while maintaining a constantmagnetic force due to the capacitive property of the PZT. So far we have succeeded the magnetic levitation and verified the advantage of zero power in stationary state. The robustness is, however, low dueto the limited variation of the magnetic force. In this paper, we propose the combination of the composite and electromagnet, where the bias gap is adjusted by the composite and the motion of the levitated yoke is stabilized by the electromagnet. The experimental results of step response verified the zero power consumption in both devices and that the composite driven by small DC-DC converter functions sufficiently to adjust the bias gap.
BibTeX:
@inproceedings{ISMB10_88,
  author = {Toshiyuki Ueno and Toshiro Higuchi},
  title = {Combination of Magnetostrictive/ Piezoelectric Materials Composite and Electromagnet for Zero Power Levitation},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_88.pdf}
}
2006 Kimman, M., Langen, H., van Eijk, J. and Polinder, H. Design of a Novel Miniature Spindle Concept with Active Magnetic Bearings using the Gyroscopic Stiffening Effect Proceedings of ISMB10  
Abstract: A high speed spindle will be designed for micro fabrication applications. The aim is to reach 0.1 µm accuracy with a rotational speed of at least 300.000 rpm. A study is done into the behavior of different rotor shapes. A short rotor and a long rotor are modeled by solving the non linear Newton and Euler equations numerically. The short rotor tilts much less under the influence of the cutting forces than a long rotor. The short rotor is thus much stiffer around the rotational axis than a long rotor. Short rotors are easier to bring up to speed. The gyroscopic coupling between the two vertical planes is much stronger in case of a short rotor. This can cause instability and must be taken into account in the design of a control system. The possibility to use this gyroscopic stiffening to our advantage will investigated. Two active magnetic bearing systems will be built. The performance of a long rotor and the performance of a short rotor, both magnetically levitated, will be compared. The design of a magnetic bearing system for a prototype with a long rotor is described in this paper. This prototype is built to gain experience in the design of small magnetic bearings, with permanent magnets for bias. The setup will be used to test the performance of a long rotor.
BibTeX:
@inproceedings{ISMB10_89,
  author = {Maarten Kimman and Hans Langen and Jan van Eijk and Henk Polinder},
  title = {Design of a Novel Miniature Spindle Concept with Active Magnetic Bearings using the Gyroscopic Stiffening Effect},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_89.pdf}
}
2006 Mizuno, T., Hirai, Y., Ishino, Y. and Takasaki, M. Active Repulsive Magnetic Bearing Using a Three-Segment Permanent Magnet Proceedings of ISMB10  
Abstract: This paper proposes a noble three-axis repulsive-type magnetic bearing that uses the motion control of permanent magnets. It has a three-segment permanent magnet of support. The motion of each segment is independently controlled with an actuator. This configuration enables the bearing to control the three-dimensional motion of the rotor. Anapparatus is fabricated for experimental study on the proposed magnetic bearing. The dynamics characteristics of the motion control system for the permanent magnets of support were measured. It was demonstrated that the proposed magnetic bearing system can achieve three-dimensional motion control.
BibTeX:
@inproceedings{ISMB10_9,
  author = {Takeshi Mizuno and Yuzo Hirai and Yuji Ishino and Masaya Takasaki},
  title = {Active Repulsive Magnetic Bearing Using a Three-Segment Permanent Magnet},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_9.pdf}
}
2006 Katoh, A. and Masuzawa, T. Optimized design for a hybrid magnetic bearing for the artificial heart Proceedings of ISMB10  
Abstract: In this study, an optimization design method is developed to design the magnetic circuit of the diagonal flow pump for the maglev artificial heart. An optimization design method of the magnetic circuit is developed with genetic algorithms. A reluctance model by using an equivalentcircuit method is used to model the magnetic bearing. Using the proposed method, we were able to optimize a magnetic bearing with an attractive force of 24.2 (N), which is larger than the desired attractive force. The magnetic bearing also has a power consumption of 1.5 (W), which is less than the expected power consumption. In addition, the size of the magnetic bearing is small enough to use for the maglev artificial heart. The developed optimization method with genetic algorithms and the reluctance model by using an equivalent circuit method is a useful design tool for magnetic bearings.
BibTeX:
@inproceedings{ISMB10_90,
  author = {Ayako Katoh and Toru Masuzawa},
  title = {Optimized design for a hybrid magnetic bearing for the artificial heart},
  booktitle = {Proceedings of ISMB10},
  year = {2006},
  url = {http://www.magneticbearings.org/wp-content/publications/ismb10/ismb10_submission_90.pdf}
}
2006 Maruyama, Y., Takasaki, M., Ishino, Y., Mizuno