A double boost 9‐level switched capacitor‐based multilevel inverter for photovoltaic applications

Abstract

SummaryA self‐balancing 9‐level inverter is proposed in this paper. To generate a 9‐level voltage with a gain of two requires a single DC source, eight power switches, three capacitors, and two diodes. Without additional circuitry, the voltages of the capacitors in the proposed topology can achieve inherent balance. The peak‐inverse‐voltage (PIV) of six power switches equals or less than the source voltage, and the other two are twice. As power switches are complementary, the proposed topology requires fewer gate drivers. Furthermore, the self‐balancing capability of capacitors' voltage helps in simple control complexity. The description of topology, mode of operation, modulation strategy, and design of the capacitor of proposed topology are presented. The advantages of the proposed inverter are examined by comparing it with switched capacitor multilevel inverters (MLIs). Finally, a 9‐level prototype is built to verify the theoretical analysis and the practical efficacy of the proposed inverter.