Topology analysis of a switched-inductor Z-source inverter

This paper presents a developed impedance-type power inverter that is termed switched-inductor Z-source inverter. To enlarge voltage adjustable ability, the proposed inverter employs a unique switched-inductor impedance network to couple the main circuit and power source. Compared with the classical Z-source inverter, the proposed inverter increases the voltage boost inversion ability significantly, and only a very short shoot-through zero state is required to obtain high voltage conversion ratios. In addition, the voltage buck inversion ability is also provided in the proposed inverter for those applications that need low ac voltages. Same to the classical Z-source inverter, the proposed concepts of switched-inductor Z-source inverter can be applied to various applications of dc-ac, ac-ac, dc-dc and ac-dc power conversion. A detailed theoretical analysis and the general discussion are given. Both simulation and experimental results verify the main analytical results.