FIVE-LEVEL SVM INVERTER FOR AN INDUCTION MOTOR WITH DIRECT TORQUE CONTROLLER

Abstract

The Direct Torque Control (DTC) is a very good control scheme for dynamic performance of speed and torque and is easy in its implementation however, decoupling of motor variables along with rotor flux axis is not required. The proposed DTC scheme uses the fundamental stator voltage vector for identification of sector for selection of switching of vector to control stator flux and the torque. In this paper, the DTC proposed usinga five-level inverter has 125 space vector switching states and among which 61are effective vectors possible. The proposed scheme is capable for enough degrees of freedom to control both electromagnetic torque and stator flux with very low ripple. From the simulation results shows that feeding electrical drive with five-level inverter can greatly improve the drive performance as compared to 2nd and 3rd-levelinverters. The performance of this control method has been demonstrated by simulations performed using a versatile simulation package, Matlab/Simulink