Design and Analysis of a Fault-Tolerant Permanent Magnet Steering Motor for Electric Vehicles

In order to solve the problems of power failure shutdown and system runaway after electrical faults, this paper proposes a highly reliable fault-tolerant permanent magnet steering motor(FTPMSM) for electric vehicles to improve the reliability and safety of the electric power steering system. Firstly, the electromagnetic scheme of the high reliability FTPMSM is designed, the arrangement of the high voltage (HV) and low voltage (LV) windings of the motor, the unequal tooth stator and the centrifugal rotor structure are determined, and the main performance indicators of the motor are defined. Secondly, analysis of FTPMSM was conducted, and the finite element model of the FTPMSM was established. The electromagnetic performance of HV winding and fault-tolerance performance of LV winding were analyzed. Then, in response to the problems of high THD of EMF and high cogging torque of the FTPMSM, the optimization scheme was determined through the analytical model. Finally, a prototype of FTPMSM was developed, and the motor experiment platform was built. Experimental research and motor performance evaluation were carried out to verify the correctness of the characteristics and theoretical analysis of the FTPMSM.