A flux-free closed-loop control for reducing torque ripple of Switched Reluctance Motor

A flux-free closed-loop strategy based on direct torque control (DTC) is proposed to solve the problem that switched reluctance motor (SRM) is prone to produce large torque ripple in commutation zone. Firstly, the closed-loop control of constant flux linkage is cancelled by analyzing the reason of large torque ripple caused by traditional DTC method. Secondly, according to the torque error signal and the inductance characteristics, the selection method of voltage vector when the torque needs to be increased or decreased at present is analyzed, and the traditional candidate voltage vector switching table is reconstructed. Finally, a 6/20 motor with permanent magnet auxiliary outer rotor is simulated and verified. The results show that the proposed control strategy can not only reduce the torque ripple of the motor, but also improve the torque-current ratio under different speed and load.