A Novel Seven-Level Inverter Based on Switching Capacitor

Aiming at the problems of many topological devices and high topological total voltage stress in existing switched capacitor inverters, a new switched capacitor seven-level inverter is proposed in this paper. Through the strategy of in-phase cascade pulse width modulation, the switching tube is rationally controlled to make the DC power supply and capacitor form different level states, and the seven-level output of the proposed inverter with triple voltage gain is realized. The topology structure, working principle, voltage stress, modulation strategy, capacitor voltage self-balance and capacitor parameters of the proposed inverter are analyzed, and the existing topology is compared with the cost function from six aspects: the number of DC input sources, the number of switching tubes, the number of diodes, the number of capacitors, the total voltage stress and voltage gain. Finally, the theory is verified by the simulation results, and the feasibility of the proposed topology is proved.