Torque Ripple Reduction of Direct Torque Controlled Induction Motor Drive by using Space Vector Modulation

Abstract

This paper proposes design and simulation of a direct torque controlled induction motor drive system based on space vector modulation technique for ripple reduction. Direct Torque Control is a control technique used in AC drive systems to obtain high performance torque control. The principle is based on simultaneously decoupling the stator flux and electromagnetic torque. DTC drives utilizing hysteresis comparators suffer from high torque ripple and variable switching frequency. The proposed SVM based DTC reduces torque ripples and preserve DTC transient merits such as fast torque response. The basis of the SVM-DTC methodology is the calculation of the required voltage space vector to compensate the flux and torque errors and its generation using the SVM at each sample period. The performance of this method is demonstrated by simulation using Matlab/ Simulink software. Simulation results presented in this paper show the torque, flux linkage and stator current ripple decreases with the proposed SVM-DTC algorithm. Experimental results are also provided to validate the proposed algorithm.