Abstract:
The quasi-Z-source inverter has the advantages of simple structure and continuous input current compared with the conventional Z-source inverter. However, the quasi-Z-source inverter with simple boost control has the problems of high voltage stress of power devices, high capacitor voltage of the quasi-Z-source network, and high inductor current ripple. In this paper, the mean signal is determined by averaging the highest and minimum values of the three-phase sinusoidal modulation signal in the simple boost control. Additionally, the mean signal is injected into the three-phase sinusoidal modulated waveform and employed in the quasi-Z-source inverter, which can effectively reduce the voltage stress of power devices and capacitors as well as the inductor current ripple. The comprehensive performance of the two modulation strategies applied to the quasi-Z-source inverter is compared by MATLAB/Simulink simulation and the RT-LAB experimental platform, and the feasibility and superiority of the proposed modulation strategy are verified based on the theoretical study.