Switched-coupled-inductor Z-source inverter with a high boost inversion capability

A novel converter with a three-winding coupled inductor, called switched-coupled-inductor Z-source inverter (SCI-ZSI), is developed based on the switched-and-coupled inductor technology in this study. Compared with the conventional switched-inductor Z-source inverter and trans-Z-source inverter, the novel inverter had a higher voltage-boosting capability. In addition, the improved topology shared a common ground point between the DC source and the inverter bridge. Under the same modulation index and load conditions, the input diode and capacitor voltage stress of the proposed inverter were lower than those of the other topologies. The operating principles, impedance-network design, voltage and current stress are presented. The theoretical findings were verified by simulation and experimental results.