Torque Ripple Reduction in PM Synchronous Motor - FEM simulation

The paper analyzes torque ripple and its reduction in Permanent Magnet Synchronous Motor (PMSM) controlled by Field Oriented Control (FOC) using advanced simulation. Created 2D Finite Element Method (FEM) model of real PMSM is in simulation coupled with FOC to investigate impact of cogging torque and impact of non-sinusoidal Back-EMF on ripple in mechanical torque and speed. Control technique which produces torque that counteracts cogging torque and impact of non-sinusoidal Back-EMF is applied. This is achieved by proper modification of q-axis current, so that q-axis current reference contains information about cogging torque profile and Back-EMF shape function to counteract their impact on torque ripple. Significantly improved motor performance in terms of torque ripple and speed ripple was achieved by appropriate q-axis current harmonics injected into PMSM.