A New Method to Minimize Voltage Stress and THD in Multilevel Z-Source Inverter Using PSO

This paper proposes a new method for minimization of voltage stress and total harmonic distortion (THD) in cascaded multilevel Z-source inverter (ML-ZSI). In this method, particle swarm optimization (PSO) is used to get the optimal values of the straight lines, modulation indexes and switching cycles for reducing the voltage stress and the THD of the phase voltage, at the desired voltage gain. The operating principle and switching algorithm of the cascaded ML-ZSI with adetailed description of suggested method are introduced in this paper. Comparison of optimization and simulation results is presented to demonstrate the capabilities of proposed method

Keywords:

cascaded ML-ZSI , H-bridge ZSI , total harmonic distortion (THD) , voltage stress , voltage gain , PSO