Cost-Effectiveness Hybrid Permanent Magnet Assisted Synchronous Reluctance Machine for Electric Vehicle

Abstract

This paper investigates a three-layer hybrid permanent magnet assisted synchronous reluctance machine (H-PMASynRM) that exhibits the most cost-effective performance for electric vehicle applications. Two kinds of permanent magnet, ferrite and NdFeB, are interchangeably used to evaluate motor performance metrics such as the torque per cost, torque density, efficiency, peak power factor, maximum speed, and rate of irreversible demagnetization. The simulation results show that the H-PMASynRM having the first layer made of NdFeB, the second layer made of ferrite, and the third layer made of a combination of ferrite and NdFeB, can exhibit the same maximum torque of 220 Nm with $12 lower cost, 1-3% higher efficiency at speed above 8,000 rpm, 6.8% lower peak power factor, and only 17% lower torque density compared to the NdFeB-based V-type PMSM that is used in Toyota Prius 2010.