Study on Electromagnetic Performance of Skewed Permanent Magnet Axial Flux Permanent Magnet Synchronous Motor

Abstract

Axial flux motors have more advantages than radial flux motors in terms of volume, torque to inertia ratio, efficiency and power density. However, when using axial flux permanent magnet synchronous motor (AFPMSM) as hub motor for electric vehicles, their torque ripples it is a thorny problem that affects its development. It is a common method to reduce the torque ripple by weakening the cogging torque. This paper studies the impact of permanent magnet deflection on motor torque ripple, efficiency and other aspects in the absence of cogging torque, that is, no stator core. Finite element simulation results show that the permanent magnet deflection of 10° is the optimal deflection angle. Currently, the electromagnetic torque pulsation is smallest, the radial air gap magnetic density waveform is closest to the sine wave, the magnetic induction intensity is the largest, and the efficiency is highest. This research result provides an effective method for reducing torque ripple of in-wheel motors.