Theoretical analysis and experimental validation of a novel multilevel inverter topology for renewable energy interfacing applications

This paper presents a new topological structure for symmetrical cascaded multilevel inverters. The proposed circuit consists of cross-connected separate symmetrical DC sources which can generate number of levels equal to that of a cascaded H-bridge topology with reduced number of power switches. It is especially suitable for utility interfacing of renewable energy sources. It also offers the possibility of a transformer less and filter less operation. The working principle of the proposed topology is explained with the help of a single-phase five level inverter. Simulation results are obtained in matlab/simulink environment and are verified experimentally on a laboratory prototype. An exhaustive comparison of the proposed topology is made with the classical cascaded H-bridge topology, especially with the considerations of conduction losses and cost-effectiveness. The proposed topology results in the reduction of number of power switches, losses, installation area, and converter cost and thus can be implem...