Noise and Output Performance in Permanent Magnet Synchronous Motor with Rotor-step Skewing

Improving the NVH (Noise, Vibration, and Harshness) quality of permanent magnet synchronous motor (PMSM) at high speeds is crucial for advanced motor design. Rotor-step skewing has been shown to play a significant role in noise reduction for PMSM. However, the rapid application of rotor-step skewing parameters in the forward design process has not been extensively reported. This paper addresses the issue of high frequency whistling noise generated by PMSM in electric vehicles at high speeds. The primary reasons of this noise are analyzed, focusing on the generation mechanism of electromagnetic force and the finite element model. By systematically investigating the influence of rotor-step skewing on noise and output performance, specifically focusing on the skewing angle and the number of segments, this study demonstrates that using four segments with a skewing angle of 7.5° is the most effective. The findings presented in this paper offer valuable insights for the forward design of PMSM, particularly in mitigating noise issues through the application of rotor-step skewing techniques.