Design and Comparison of Six-Phase Fault-Tolerant Interior Permanent Magnet Motor and Surface-Mounted Permanent Magnet Motor for Electric Vehicles

In this paper, we design and investigate the six phase in-wheel fault-tolerant surface-mounted permanent magnet motor (SPM) and interior permanent synchronous motor (IPM) for electric vehicles (EVs) application. Firstly, the stator of the motor is designed based on the anti-short-circuit method and the main design parameters of both motors are listed. Then the electromagnetic performance and the motor loss of both motors are analyzed by finite-element analysis (FEA). In addition, the thermal analysis is conducted by utilizing Motor-CAD, which shows that both SPM and IPM encounter with magnet overheating problems. Therefore, the magnet segmentation basing on the skin depths calculation is adopted to reduce the eddy-current loss. Meanwhile, the thermal performance of both motors with non segmented and segmented magnets under different working conditions are presented. Finally, the optimized model is achieved through the comparison between the two types of fault-tolerant permanent magnet synchronous motors (FTPMSM).