Research and application of high frequency isolated Quasi-Z-source inverter

Compared with the traditional inverters, Z-source/Quasi-Z-source inverters have better electrical characteristics. The inverter can cover the shortage of traditional inverter. The impedance network makes the inverter can boost or buck input voltage in any ratio. And the shoot-through question in traditional inverter is not in considered here. This kind of inverter is very suitable to be used in photovoltaic power generation system with wide range input. In this paper, the new proposed high frequency isolated quasi-Z-source inverter is been studied in-depth. The paper gives its small signal modeling method and application in grid-connected PV system. The control strategy used here is making the peak of dc bus voltage constant, which ensures the unity of MPPT stage and inverter stage. At last the paper gives the results of simulation with saber.