A Novel TSF Control Method with an Adaptive Turn-On Angle in Three Regions to Suppress Torque Ripple in Permanent Magnet-Assisted Switched Reluctance Motor

Compared to switched reluctance motors, permanent magnet-assisted switched reluctance motor (PMa-SRM) have higher torque density, but the torque ripple remains severe, especially under high speeds or a heavy load. A novel torque shared function (TSF) control method with an adaptive turn-on angle in three regions is presented in this paper in order to suppress torque ripple. Firstly, the inductance and flux linkage of the PMa-SRM is presented, and the look-up table of the current is obtained by the inverse interpolation method to build the PMa-SRM model. Secondly, the reason for torque ripple caused by conventional TSF is explained. Thirdly, the two-phase exchange (TpE) region is sub-divided into two regions, and the control method in each region is set accordingly. An adaptive turn-on angle algorithm is designed, which can automatically accommodate different speeds and loads. Finally, simulation and prototype tests verify that the novel TSF control method could validly suppress the torque ripple of the PMa-SRM in a wide speed range.