Identification of optimal SVPWM technique for diode clamped multilevel inverter based induction motor drive

Abstract

Multilevel inverters (MLI) are employed mainly to enhance the performance of the drive scheme which generally demands a quality power source. The modulation technique involved plays a vital role in its improvement. The conventional sine pulse width modulation (SPWM) scheme employed in this regard though suffers from various limitations resulting in drives with lesser efficiency. Hence Space Vector Pulse Width Modulation (SVPWM) techniques are becoming popular in inverter systems due to its advantages in better utilization of input voltage, lesser harmonic content and better output voltage profile, especially from the drive system point of view. The disadvantage being the complex computations involved. This paper envisages to identify the optimal SVPWM technique for diode clamped MLI. The conventional SVPWM and the proposed SVPWM techniques are applied to the diode clamped MLI fed induction motor drive. The performance of both the drive schemes are analyzed and compared, to show the effectiveness of the proposed method. The added advantage of the proposed technique is that it involves lesser computations and has generalization capability.