Torque Ripple Suppression of Doubly Salient Reluctance Motor by Injecting Harmonics into Zero-sequence Current

Compared with the Induction Motor and Permanent Magnet Synchronous Motor, the doubly salient reluctance motors (DSRMs) have the advantages of simple structure, wide speed control range and low cost. However, due to the doubly salient structure of the stator and rotor, this kind of motor has lots of torque ripple, and the DSRM performance is decreased. In order to reduce torque ripple, a method to suppress torque ripple by injecting specific harmonics into zero-sequence current is proposed. Firstly, the structure of DSRM and open-winding inverter is introduced. Then, the amplitude and phase of the injected harmonics are obtained by analyzing the electromagnetic torque equation. Lastly, the correctness of the suggested method on DSRM is confirmed by experiments.