Investigation of a 3D-magnetic flux PMSM with high torque density for electric vehicles

• Main Authors: Chen, Hao, Demerdash, Nabeel A. O., El-Refaie, Ayman M., Guo, Youguang, Hua, Wei, Lee, Christopher Ho Tin
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2022
• Subjects: Engineering::Electrical and electronic engineering; 3D-Magnetic Flux; Electric Vehicle
• Online Access: https://hdl.handle.net/10356/158976
• Institution: Nanyang Technological University

This paper presents an investigation of a 3D-magnetic flux permanent magnet synchronous motor (3D-MF PMSM) used for electric vehicle applications. The investigated 3D-MF PMSM consists of an integrated radial-flux and axial-flux structure. It has two radial-flux air-gaps and two axial-flux air-gaps, as well as a toroidal winding wound stator. The integrated structure helps to concentrate all the flux within the motor to maximize torque production. Moreover, there are no end-windings in this motor and all the stator windings effectively are used in torque production. A comprehensive performance evaluation, in terms of the back-electromotive force, average output torque, cogging torque, torque ripple, flux-weakening capability, etc., of the investigated 3D-MF PMSM is conducted. An interior PMSM is purposely included as a benchmark for comparison. The results show that compared to the benchmark interior PMSM, the original 3D-MF PMSM exhibits significantly improved torque density, higher power factor, and higher efficiency, but suffers from serious cogging torque and torque ripple. Accordingly, an unaligned arrangement is introduced to the 3D-MF PMSM. As a result, the cogging torque and torque ripple are significantly reduced.