Application and Research of the Active Magnetic Bearing in the Nuclear Power Plant of High Temperature Reactor

The 10MW High Temperature Gas-cooled Test Reactor (HTR-10) constructed by the Institute of Nuclear and New Energy Technology (INET) of Tsinghua University in China, is the first modular high-temperature gas-cooled test reactor (HTR) in the world. When combined with the direct gas-turbine cycle, HTR achieves high inherent safety together with high efficiency. Besides, the possibility of water ingress in the core can be eliminated, the power unit design can be simplified and the construction capital and operational costs can be reduced. HTRs are thus considered as one of the most potential candidates for the new generation reactors in the 21st century. The direct gas-turbine cycle requires some kind of special designed bearings to support the shaft on which the gas compressors, turbine and generator are all installed in the primary loop. However, the design of the special bearings is a challenge task. Thanks to the rapid development of the Active Magnetic Bearing (AMB) in recent years, the contact-freeand no-lubricating AMBs are regarded as the most competent option to support the turbomachine shafts in all the designed gas-turbine HTRs for their numerous advantages over conventional bearing technology. Two projects, HTR-10GT (HTR-10 Gas Turbine) and HTR-PM (HTR-Pebble-bed Module) initiated by INET, will consider incorporating the AMS technology in their power conversion systems. This paper focuses on the introduction of AMB applied to the power system of HTR, the design characteristics of the AMB system and the introduction of the related series of experiments to demonstrate the system functions and validate the control scheme to be used in the HTR-10GT and HTR-PM project.