Performance Analysis of Z-Source Inverter Control Techniques

Abstract

This study presents the different control techniques of the Z-Source inverter (ZSI) and compares them for the same modulation index. Different from the traditional inverters, in ZSI circuit configurations simple boost, maximum boost, and maximum constant boost control techniques can be utilized to perform DC-AC voltage conversion with shoot-through states. The operation principles of the control techniques are explained in detail. The shoot-through duty ratio, the boost factor, and the voltage gain for each control technique of the ZSI are calculated using the related equations. The ZSI circuit model and the simulations of the DC-link and the AC output voltage are performed in Matlab/Simulink environment. According to the related equations used in the different control techniques and the obtained simulation results, the maximum boost control technique has the highest boost factor and voltage gain for a determined modulation index. For that reason, the maximum boost control technique has the maximum equivalent DC-link voltage and AC output voltage under the same conditions. This control technique can be employed for inverter applications where the highest gain is required.