Hysteresis-PWM direct instantaneous torque control of switched reluctance motor

Switched reluctance motor has the characteristics of torque ripple. A direct instantaneous torque control strategy combining hysteresis control and pulse width modulation (PWM) is proposed in this paper. The method worked in single-phase mode, analyzed the mechanism of large fluctuations in torque during control process, and formulated differen control methods for single-phase and commutation zones. The strategy took into account the shortcomings of the torque ripple caused by the free-response of the hysteresis controller between the positvie and negative hysteresis limits, and introduced the PWM equivalent strategy into the hysteresis limits to optimize the torque control effect. Experiments show that this strategy combining hysteresis strategy and PWM strategy fully considers the output characteristics of torque under different conditions. The optimized switching strategy applies the corresponding winding voltage under different torque errors. The control effect of the proposed strategy is better than that of the hysteresis strategy, which reduces the torque ripple and optimizes the performance of the control system. © 2020, Harbin University of Science and Technology Publication. All right reserved.