Simple analytical derivation of magnetic flux profile eliminating source current ripple and torque ripple of switched reluctance motors for electric vehicle propulsion

Abstract

This paper proposes a simple control technique for switched reluctance motors to eliminate both the source current ripple and the torque ripple simultaneously. The proposed control is a current tracking control based on a pre-computed magnetic flux profile. This profile is derived using a simple analytical SRM model without the magnetic saturation. Conventionally, the magnetic saturation is commonly utilized for limiting excessive magnetic flux induction to improve the torque output. However, in the proposed control, the magnetic flux profile is utilized for limiting the magnetic flux by control. By controlling without the magnetic saturation, elimination of the source current ripple and the torque ripple can be achieved regardless to the output power. Along with theoretical derivation of the magnetic flux profile, an experiment is carried out to evaluate the proposed control. The results revealed suppression of the source current ripple and the torque ripple simultaneously in comparison with the conventional square-wave current control.