A Comprehensive Study of Multilevel Inverter fed Switched Reluctance Motor for Torque Ripple Minimization with Multicarrier PWM Strategies

Abstract

This paper portrays the comprehensive study of torque ripple minimization of a Switched Reluctance Motor (SRM) using the multilevel inverter (MLI) with various pulse width modulation (PWM) techniques. In modern era, the usage of switched reluctance motor increases widely in industrial areas. But, it has the limitations as high torque ripple which leads to the very noisy operation. For minimizing the torque ripple, the conventionally used normal converter has been replaced with cascaded H-Bridge MLI. MLI plays the vital role to reduce the total harmonic distortion (THD) in the source current which was fed to the SRM stator winding. Here, the four phase 8/6 SRM is obtained by using MATLAB/Simulink model which was fed by seven level inverter. A comparative study has been done by using various multi carrier based PWM techniques such as phase disposition, phase opposition disposition method, alternate phase disposition method, variable amplitude and variable frequency carrier based methods are incorporated in the multilevel inverter. Since, the higher value of harmonic distortion leads to the higher torque ripple in SRM, the optimal PWM method for the inverter is obtained to lower the harmonic distortion in the source current from this comprehensive study.