Torque ripple minimization of Switched Reluctance Motors using speed signal based phase current profiling

Switched Reluctance Motor (SRM) has significant ripple in the total output torque production. The torque ripple is reflected in the speed through mechanical dynamics of the drive system. In this paper the ripple in the speed signal is used in closed loop control, to minimize the torque ripple during commutation. The speed signal can be obtained through speed sensor or estimator, which is less complicated and more cost effective than using a torque sensor. In spite of being filtered by the inertia, the ripple information can be extracted from speed signal using signal processing mechanism. This paper shows that properly extracted signal has acceptable correlation in terms of shape with the torque ripple. The acquired ripple information is used for the SRM phase current shaping during commutation and results show that the proper shaping of current in the commutation portion has minimized the torque ripple significantly.