Capacitor voltage balancing control for CHB multilevel inverter considering harmonic distortion based on Programmed Matrix PWM

Abstract

In this paper, a programmed matrix pulse generator is developed to generate PWM controls signals synchronized with switching angles which are obtained as a result of Trust-region Dogleg analysis. Trust-region Dogleg method is more flexible and efficient than conventional optimization techniques and it can be extended to any m level CHB multilevel inverter operating at any switching frequency. Programmed matrix PWM allows balancing CHB multilevel inverter capacitor voltages, eliminating certain harmonic orders and avoiding dead time insertion in commutation cells control signals. Performance of the proposed method for a five-level cascaded H-bridge inverter, based on simulation studies, is evaluated and experimentally verified.