Fast and Accurate Radial-Flux PMSM Step-Skewing Computation Methodology for NVH Improvements Across the Machine Full Operation Range

This paper proposes an electromagnetic/vibro-acoustic coupled simulation methodology using fast and accurate reduced-order models for optimal Permanent Magnet Synchronous Machines step-skew design. The electromagnetic model is obtained by conducting 2D electromagnetic finite-element analysis on a non-skewed design and tabulating the extracted torque and air-gap flux-density results. The vibroacoustic reduced model is represented by the vibroacoustic responses obtained from applying spatially distributed unitary force shapes to segments of the inner stator teeth area. The total response is computed using the vibration-synthesis method across the whole torque-speed range for operation conditions obtained from the torque-to-current controller optimization routine, generating vibroacoustic maps for the most significant orders. This allows the analysis of structural and acoustic metrics for different types of axial step-skew configurations and different skew angles in a computationally efficient way across the machine's full operation range.