Operating Characteristics Analysis of Multi-phase Bearingless Permanent Magnet Slice Motors With Faulty Phases

In order to solve the problem that fault of the phases would lead to multi-phase bearingless permanent magnet slice motors’ abnormal operation,an improved fault-tolerant control strategy is presented based on the fault-tolerant control strategy with open-circuit phase（s）.Taking into account the part of levitation forces and torque which the faulty phases provide,the desired currents of the normal phases are reconfigured.And a general fault-tolerant controller for several possible fault modes is achieved.Meanwhile,a fault self-diagnosis method through the feedback of phase currents is introduced.The simulation and experimental results have verified the proposed fault-tolerant control strategy.