Investigation of a 3D-Magnetic Flux PMSM With High Torque Density for Electric Vehicles

• Published in: IEEE transactions on energy conversion Vol. 37; no. 2; pp. 1442 - 1454
• Main Authors: Chen, Hao, Demerdash, Nabeel A. O., EL-Refaie, Ayman M., Guo, Youguang, Hua, Wei, Lee, Christopher H. T.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.06.2022; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: 3D-magnetic flux; Back electromotive force; Benchmarks; Cogging; Coils (windings); Density; electric vehicle; Electric vehicles; Electromotive forces; flux-weakening capability; high torque density; Induction motors; Investigations; Magnetic flux; Magnetism; Performance evaluation; Permanent magnet motors; permanent magnet synchronous motor (PMSM); Permanent magnets; Power factor; Ripples; Rotors; Stator windings; Stators; Synchronous motors; Torque; Traction motors; Windings
• ISSN: 0885-8969; 1558-0059
• DOI: 10.1109/TEC.2021.3137803

This paper presentsan 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, a skewed arrangement is introduced to the 3D-MF PMSM. As a result, the cogging torque and torque ripple are significantly reduced.