A Graphical Approach to Switching Losses and Harmonics Distortion For Carrier SVPWM Methods In Multilevel Inverters

This paper presents a simple graphical approach to compare the switching losses of various carrier SVPWM methods for multilevel inverters. Similarly, the harmonic distortion factors can be indirectly validated. There have been deduced SVPWM methods related to maximum, medium and minimum zero sequence functions. As a result of comparison, the SVPWM with optimized switching loss and THD factor has been proposed. The investigation shows that the maximum/minimum offset SVPWM would be superior to others for lower modulation index and the medium/minimum common mode SVPWM can obtain advantages in the medium and high modulation index range. The proposed SVPWM methods have been mathematical formulated and demonstrated by simulation results.

I. Introduction

Nowadays, multilevel inverters have achieved an increasing contribution in high performance applications. The two most popular PWM methods are carrier based and space vector types [1]–[2].