Torque Ripple Reduction in Direct Torque Control Induction Motor Drive Using Svm and Fldrc

Direct Torque Control (DTC) is a control technique used in AC drive systems to obtain high performance torque control. The conventional DTC drive contains a pair of hysteresis comparators, a flux and torque estimator and a voltage vector selection table. The torque and flux are controlled simultaneously by applying suitable voltage vectors, and by limiting these quantities within their hysteresis bands, de-coupled control of torque and flux can be achieved. However, DTC drives utilizing hysteresis comparators suffer from high torque ripple and variable switching frequency. This work aims at developing a DTC scheme for induction motor, with reduced toque ripple, using fuzzy logic duty ratio control (FLDRC) and Space Vector Modulation (SVM) techniques. From the simulation results shows that feeding electrical drive with proposed system greatly improves the drive performance. The performance of this control method has been demonstrated by simulations performed using a versatile simulation package, MATLAB/SIMULINK.