A Novel Z-source Inverter with Voltage Multiplier Cells

The traditional single-stage boost inverter can overcome the disadvantages of incompatibility between boost and inverter, owing to the structure of the topology, the boosting capability of this type of circuit is limited by the modulation factor M, and cannot fully exploit its advantages. Aiming at the existing technical defects, this paper proposes a high-boost single-stage inverter, which uses voltage multiplier cells of dc-link and shoot-through state of inverter-link to realize dual degree of freedom adjustment of the AC output voltage, a large boost factor can be obtained when the duty ratio is low. The buffering effect of the capacitor can effectively reduce the switch-voltage spikes of the dc-link voltage, and the inverter effect becomes more prominent. Therefore, proposed inverter is suitable for the inverter with high boosting requirements for photovoltaic grid connection. This paper describes the working state of the inverter, and carries out theoretical analysis and simulation verification, and then compares with the circuit parameters of the classical converter. Finally, the 600W experimental prototype was built for verification. The experimental results were consistent with the theoretical analysis and simulation results, and the correctness and feasibility of proposed inverter were verified.