Generalized Multicell Switched-Inductor and Switched-Capacitor Z-Source Inverters

Traditional voltage-source inverter is limited by its only voltage step-down operation, while current-source inverter is limited by its only current step-down mode. In order to add an extra boosting flexibility while keeping the number of active semiconductors unchanged, voltage-type and current-type Z-source inverters were earlier proposed. These new classes of inverters are generally more robust and less sensitive to electromagnetic noises. However, their boosting capabilities are somehow compromised by high component stresses and poorer spectral performances caused by low modulation ratios. Their boosting gains are, therefore, limited in practice. To overcome these shortcomings, the generalized switched-inductor and switched-capacitor Z-source inverters are proposed, whose extra boosting abilities and other advantages have already been verified in simulation and experiment.