A quasi‐Z‐source inverter with a single high‐frequency‐switch

SUMMARY In this paper, a high efficiency quasi‐Z‐source inverter with a single high‐frequency switch is proposed to achieve a high efficiency and more compact topology. The converter utilizes a single high‐speed GaN FET. In the proposed converter, four switches operate with low frequency sinusoidal pulse width modulation while the fifth switch short circuits the inverter switch‐legs with a high switching frequency and prepares the shoot‐through current path. The operation of the fifth switch in high switching frequency helps the inverter to operate with modulation index equal to unity. Also, the impedance network operates in high switching frequency, which makes it possible to decrease the components' size. The operation principles, efficiency, and switches' losses of the proposed converter are investigated analytically. A comparison between theoretical and simulation results is performed to validate the theoretical description of the inverter. To validate the well‐behavior of the inverter under various operation modes, the performance of the proposed converter is examined under different types of load. Moreover, loss breakdown and efficiency comparisons are utilized to show improvements with respect to the conventional inverter. The performance of the converter has been examined and validated through a 300 W prototype of the inverter. A five switch quasi Z‐source inverter with a single high frequency switch providing high efficiency in compact size. The proposed inverter utilizes two different switching frequencies. The single high frequency switch is responsible to minimize the impedance network size, while the other four switches work in low frequency to yield high efficiency.