A Novel Step Current Excitation Control Method to Reduce the Torque Ripple of Outer-Rotor Switched Reluctance Motors

Abstract

Featured in low-speed and high-torque operation, outer-rotor switched reluctance motors (OSRMs) have the potential to be widely deployed in low-speed commuter and logistics vehicle applications. In this paper, a five-phase OSRM and the control method featuring torque ripple reduction has been proposed, which can be applied as the wheel hub motor in the electric vehicles. The simulation was carried out to analyze the OSRM operation. The electromagnetic characteristics of single-phase and two-phase hybrid excitation mode, as well as step current excitation mode, were compared and analyzed. To solve the problem of the large torque ripple of OSRMs under traditional excitation modes, the torque ripple suppression method based on step current excitation was also studied. The experiment design, including motor start-up control, speed control, and torque ripple reduction, are presented to verify the system torque ripple mitigation method.