High boost switched capacitor based 13L CG transformerless inverter for cost effective grid integration

Transformerless inverter topologies with common ground features in solar photovoltaic and grid-connected systems are increasingly preferred due to their ability to effectively suppress leakage current to approximately zero, eliminate transformer-induced losses, and achieve improved energy conversion efficiency. This article presents a high-boost switched capacitor thirteen-level (13L) common ground transformerless inverter topology (HBSC-13L-CGTLI) with a voltage gain of six and reduced cost. Further, the maximum voltage across the switch is 67% of the output voltage, which reduces the cost of the inverter. The proposed topology does not need any separate circuit for its negative voltage level generation. The proposed topology generates a 13L output voltage at the load terminal using a single DC source, thirteen switches, four switched capacitors and three diodes. A detailed description of operational modes, design of the switched capacitor and filter inductor, and loss analysis of the proposed topology is presented. The performance of the proposed topology is validated through MATLAB/Simulink simulations and experimental results from a 1 kW laboratory prototype under various operating conditions. Finally, a detailed, comprehensive comparison of the different 13L inverter topologies is carried out to demonstrate the superior features of the proposed topology.