Research For Fault-tolerant Control Of Five Phase Permanent Magnet Synchronous Machine

At present, due to its excellent performance the PMSM has been widely used. Becausee of its ability of fault-tolerant, it has been received more and more attention, in many areas, such as the aerospace, entire electric power drive research for ships as well as submarine, electric cars and some other special industrial areas. Therefore, it has been considered as a research hotspot gradually.The so-called motor fault-tolerant operating ability means when something fault appears in the motor itself or control system, through equipment redundancy or imposing reasonable fault-tolerant control strategy the motor is still able to continue running smoothly.In this paper, the main purpose is to do the research for the suitable fault-tolerant control strategy to open circuit fault of motor. The basic idea is to apply the synthetic vector method to five-phase permanent magnet synchronous motor to solve the problem caused by the single-phase open circuit fault and determine the effective fault-tolerant control strategy further.In this paper, five-phase PMSM has been studied respectively under the condition of normal as well as fault-tolerant operation. During the course of normal operation, the five-phase current are uniformly distributed in space, which can generate a circular rotating field with constant amplitude as well as output the stable torque. In the case of a single-phase open-circuit failure, through imposing the reasonable current control strategy can result in the motor operating under the condition of fault-tolerant, and the remaining normal current could rebuild a circular rotating field, which would guarantee output torque to be still stable.Finally by using the professional software of finite element analysis, the simulations of five-phase PMSM operating under the normoal as well as fault-tolerant condition have been carried out respectively. And the simulation results such as the electromagnetic field as well as output torque have been analyzed and compared in detail. According to the results of analysis and comparison, it can provide the direct and persuasive evidences to further verify the correctness and feasibility of the adopted fault-tolerant control strategy.