Switched-Inductor Extended-Boost Quasi-Z-Source Inverter

This paper introduces two novel impedance source inverter topologies for switched-inductor extended-boost quasi-Z-source inverters: diode-assisted and capacitor-assisted switched-inductor extended-boost quasi-Z-source inverters. The proposed topologies exhibit a significant voltage boost capability while operating at a lower shoot-through duty ratio. These inverters can operate at higher modulation indices by employing a low shoot-through duty ratio, improving the output voltage performance and reducing the stress on inverter switches. A comprehensive analysis of the operation of inverters in both the shoot-through and non-shoot-through states was performed. Mathematical derivations were provided to determine the boost factor and design the impedance network parameters. The theoretical analysis was further validated through computer simulations using the PSCAD software and experimental results. A laboratory prototype was constructed to verify the simulation results and demonstrate the high-gain capabilities of the proposed inverters. A detailed analysis of the capacitor voltages, diode stress, and switch stress of the proposed inverters was performed. These parameters were compared with the existing inverter topologies documented in the literature. This comparison offers insights into the superior performance and advantages of the proposed diode-assisted and capacitor-assisted switched-inductor extended-boost quasi-Z-source inverter.