An improved SVPWM method for multilevel inverters

Abstract

This paper proposes a new general Space Vector PWM (SVPWM) method for Multi-Level Inverters (MLI) based on a generalization of dwell-times calculation. The presented scheme is developed for Cascaded H-Bridge (CHB) inverter. In the proposed strategy, the sectors are defined by two parameters serving for the easy calculation of dwell-times. A very simple mapping is used to achieve the SVPWM for any n-level inverter. In addition a dead-band hysteresis is introduced in the SVPWM algorithm to avoid the output voltage level jumping. The simulation results show the effectiveness of the proposed method.