High voltage gain switched z‐source inverter with low current stress

Abstract

AbstractThis paper proposes a switched Z‐source inverter with high voltage gain and low current stress on elements. Also, a new switching method corresponding to the proposed topology is introduced. This method is based on the usual Maximum Constant Boost (MCB) method. Hence, it has the advantages of the MCB method, such as low voltage stress on the inverter switches and high voltage gain. Also, eliminating part of the inverter's switching in this modulation method improves the inverter's efficiency. In addition to the Shoot‐Through (ST) duty cycle, another variable (N) affects the inverter's boost factor in this switching method. The proposed inverter's dynamic analysis shows that introducing N in the modulation method improved the dynamic characteristic of the inverter. Also, this variable as a control input can stabilize the dc side of the inverter in the closed‐loop control of the inverter. For the proposed topology, steady‐state analysis, dynamic analysis, elements design and efficiency calculation are performed. Also, the proposed topology is compared with the conventional topologies regarding boost factor, the number of elements, current stress on elements and efficiency to show its superiority. Finally, the experimental results are presented to verify theoretical discussions.