A Design of Robust Servo Controllers for an Unbalance Vibration in Magnetic Bearing Systems

This paper deals wiLh the problem of all unbalance vibralion in magnetic bearings. An efficient damping control scheme for the vibration is proposed. First, the state equation of a magnetic bearing system in which unbalance of a rolor is taken into consideralion is shown. Next, the control system achieving the rotalion around the geomelrical axis is proposed. Here we formulale the conlrol problem within a framework of the so-called Robust Servomechanism problem, and we design the control law using the Selective Turn-over method. Finally, the effectiveness of the control system is actually confirmed by several experimental results.