Repetitive Control-Based Torque Ripple Reduction Method for SRM Drive

In this paper, a torque ripple suppression strategy of SRM based on repetitive control was proposed. Due to the doubly salient structure of SRM, the rate of rising current and falling current is different in the current commutation period, which leads to a large fluctuation of electromagnetic torque. In the conventional current chopping control, the current would exceed the hysteresis range in practical application due to the insufficient switching frequency. Therefore, a repetitive controller has been used in the speed loop to generate a periodic current reference signal, which can improve the reference current in advance. And the improved soft current chopper control combined with PWM is adopted in current loop to reduce the torque ripple caused by current overshoot in the single-phase excitation stage. In this paper, an SRM control system based on repetitive control has been constructed. The proposed control strategy is verified by simulation, and the FFT analysis is used to illustrate the effect of the strategy on the suppression of torque ripple, which proves that the proposed control method can effectively reduce the torque ripple.