Switched-Capacitor Based Modified Extended High Gain Switched Boost Z-Source Inverters

Abstract

Two novels switched Z-source inverters (ZSI) based on the active switched capacitor with high voltage conversion ratio are presented. These are active switched capacitor-based capacitor assisted extended boost ZSI and diode assisted extended boost ZSI. High voltage gain is required in various applications such as electric vehicles, grid integration of renewable energy sources, etc. The voltage gain of conventional ZSIs are limited and these conventional ZSI has high voltage conversion ratio at a high duty cycle, which results in poor inversion and poor efficiency. In this work, only one additional diode and one active switch are used with the conventional extended boost ZSI to achieve high voltage conversion ratio without adding any additional passive components. Compared to other ZSI topologies, the proposed inverter also guarantees low voltage across capacitors, a wide range of duty cycle operation and continuous source current in addition to high voltage conversion ratio. The detailed operating principles and steady-state analysis and design details are presented. The performance of the inverters is verified through simulation and also through experiments. Both the simulation and experimental results are presented.