SVM strategy and analysis of a three-phase quasi-Z-source inverter with high voltage transmission ratio

Herein, we propose a novel three-phase quasi-Z-source inverter with a high voltage transmission ratio to address challenges such as high switching loss and sizeable magnetic components in the basic quasi-Z-source inverter. The proposed circuit topology, control strategy, and related analysis are presented. The circuit topology of the inverter comprises a quasi-Z-source network with an integrated magnetic inductor, an active clamp circuit, a three-phase inverter bridge, and an output LC filter, all of which are connected in series. An improved 12-sector space vector modulation scheme is proposed based on the root-mean-square value of the voltage and the instantaneous value of the current. Furthermore, analyses of the inverter voltage transmission ratio, resonant process, and parametric design guidelines for integrated magnetic inductor and zero-voltage switching conditions are presented. Experimental results on a 1-kVA prototype inverter demonstrate that the proposed inverter exhibits a higher transmission ratio and efficiency than existing inverters; thus, the proposed inverter would have broad prospects in low-voltage DC-AC applications.