Modeling of permanent magnet synchronous machine including torque ripple effects

A model of permanent magnet synchronous machine (PMSM) including the electromagnetically originated torque ripple is presented in this paper. This unique representation of such equivalent circuit is highly critical to understand the torque ripple content and to develop an appropriate mitigation scheme for low torque ripple applications requiring four quadrant operations. This research proposes a method to quantify the various sources of torque ripple and modifies the existing DQ-model to enhance the modeling capabilities for both surface-mount and interior PMSMs. The study also presents the effect of slot/pole combination on torque ripple contents by analytical and finite element modeling. Finite element analysis is used for modeling various PMSMs to verify the lumped circuit model proposed in this research. The theoretical results obtained from analytical and finite element analysis are validated using experimental test.