Symmetric and asymmetric transformer based cascaded multilevel inverter with minimum number of components

In this study, a novel transformer based cascaded multilevel inverter is presented. The proposed inverter can operate in both symmetric and asymmetric topologies. The presented inverter benefits from the advantages such as reduced number of power switches and reduced total peak inverse voltage of the switching components. The numbers of insulated gate driver circuits are also decreased with respect to the power switches. Furthermore, the presented topology requires just a single DC source. In addition, the numbers of on-state switches in the current paths are reduced. Therefore the voltage drops across the switches are mitigated and as a result the efficiency of the presented inverter is improved. The mentioned advantages cause the implementation cost to be reduced. The operation of the converter is discussed thoroughly for both symmetric and asymmetric operations. The feasibility of the presented inverter topology is validated using the simulation results. Experimental results under 1.5 kW are also added to justify the theoretical analyses.