Comparison of SVPWM and SPWM Schemes for NPC Multilevel Inverter

Abstract

The aim of this paper is to use Space Vector Pulse Width Modulation (SVPWM) technique and Sinusoidal Pulse Width Modulation (SPWM) technique to mathematically prove and compare the DC bus utilization for a Neutral Point Clamped (NPC) three level Inverter. The comparative analysis between SVPWM and SPWM is made in the linear region of Modulation Index. The analogous relationship between the modulation indices for SPWM and SVPWM is presented here. Besides this it is also shown that Total Harmonic Distortion (THD) is lower for SVPWM technique than SPWM technique. The results are simulated for a NPC three level Inverter feeding RL load with the help of MATLAB/SIMULINK.