A permanent magnet traction machine with wide high efficiency range for EV application

Due to the difference in the working condition and operating mode, permanent magnet (PM) traction motors design concept significantly differs from the traditional industrial motor. Optimization design of the PM traction motor with wide high efficiency range for electric vehicle (EV) application is investigated in this paper. Firstly, the basic design principle and dimension constraint are analyzed and determined. Secondly, the split ratio, the angle between the V-type magnet, slot depth and tooth width are optimized by finite element analysis (FEA) under different working conditions. Furthermore, simulations implemented on the traction motor demonstrate that the wide high efficiency range can be obtained by optimization. Finally, comprehensive experiments have been implemented on a traction motor prototype to validate the feasibility of the traction motor design scheme.