Switching Losses and Harmonic Currents Evaluation of PWM Techniques for VSI-Fed Dual Stator Induction Motor Drive

In this paper, an analytical evaluation of the harmonic currents and the switching losses in dual stator induction motor (DSIM) drive fed by two three-phase VSIs controlled by PWM techniques is presented. Based on the sine-triangle and space vector PWM techniques concept, eight variants of PWM strategies are presented and compared. So, continuous (CPWM) and discontinuous (DPWM) PWM techniques are obtained according to the selected switching sequences. The analysis is applied to determine the optimal modulation technique that minimizes the switching losses and the rms value of the harmonic currents. It is shown that the CPWM at low modulation and DPWM techniques at the high modulation range have superior performance. Whereas, reduced switching losses are obtained with the DPWM techniques. Therefore, an optimal PWM scheme is obtained with transition between these PWM strategies to allow a performance drive optimization over the whole voltage range.