An Injected High Frequency Current Reference Generation Method for Torque Ripple Reduction in PMSM

Abstract

Permanent-magnet synchronous motors (PMSMs) are used for traction application in electric vehicles (EVs) and hybrid electric vehicles (HEVs). However, PMSMs generate vibration and acoustic noise in the connected load due to torque ripple. Torque ripple reduction techniques require accurate modeling of torque ripple and estimation of motor parameters considering magnetic saturation and magnet temperature variation. Existing approaches that consider magnetic saturation and magnet temperature variation are complicated and difficult to realize. Therefore, this paper proposes a torque ripple expression which is regarded as complex vector behavior. It can easily determine the high harmonic current reference to reduce the torque ripple by geometrically expressing the torque ripple. Furthermore, the effect of the proposed method of torque ripple reduction was experimentally verified.