Minimization of torque ripple using DITC with optimum bandwidth and switching frequency for SRM employed in electric vehicle

Abstract

This paper presents the modeling and simulation of two-level and three-level Direct Instantaneous Torque Controller (DITC) for Switched Reluctance Motor (SRM) employed in electric vehicle. DITC is implemented taking torque as control variable and is estimated from the look-up table by considering current and rotor position of SRM. Further, PI controller is designed using symmetrical optimum method and integrated with two-level torque controller. Performance of two-level torque controller with and without PI controller is observed in terms of torque ripple for various bandwidths and switching frequency. It is observed that, the contribution of PI controller in terms of torque ripple minimization is not remarkable. In this regard, three-level torque controller is implemented in order to achieve the better performance and desired features for the operation of SRM in electric vehicle (EV). Finally, performances of two-level and three-level torque controller are compared in terms of minimum torque ripple, wide speed operation, high starting torque and converter switching frequency. It is observed that three-level torque controller has better performance than two-level controller for SRM employed in electric vehicle.