A Comparison between Different PWM Methods of Three Phase Z-Inverter for Renewable Energy Applications

The aim of this paper is to investigate the ability of Z-source inverter to overcome the problems of conventional inverter. Conventional inverter has many problems such as dead-beat compensation, steeping problem, and miss-gating problem.  In addition, Z-source inverter in comparison with other impedance source converters in case of small duty has high voltage gain. Three pulse-width modulation (PWM) techniques of Z-converter are analysed and compared. Simple boost PWM, maximum boost PWM and (SVPVM) space vector PWM methods are analysed and compared. The boost gain, voltage output gain and switches stress equations of each method are deduced. The performance of the three pulse width modulation methods is evaluated under different load conditions and variable input voltage. Simulation work is carried out using MATLAB/Simulink package to evaluate the proposed method performance. Keyword: Z-source inverter, conventional inverters, Simple boost PWM, maximum boost PWM and space vector PWM.