A New Space Vector Modulation Technique for Reducing Switching Losses in Induction Motor DTC-SVM Scheme

Direct torque control (DTC) scheme is one of the most appropriate methods to control of AC machines. This method has positive features such as fast response, simple structure and low dependence on motor parameters. However, the main problems in classic DTC method are variation of switching frequency and high ripple of flux and torque. These problems are approximately solved in the literature using advanced controllers and space vector modulation. Nevertheless, this paper presents a new DTC method using space vector modulation (DTC-SVM) in three-level cascaded H-bridge (CHB) converter, which has less switching losses than the conventional SVM (CSVM) methods. The proposed method uses switching sequences according to the reference voltage modulation index, which reduces the number of switching commutation and switching losses. Finally, the performance of the proposed method is presented through simulations in MATLAB/SIMULINK software.