A New Basic Unit for Symmetric and Asymmetric Cascaded Multilevel Inverter with Reduced Number of Components

This study suggest a new basic structure for symmetric and asymmetric cascaded topologies with reduced number of power electronic components. This topology generates 10 voltage steps by three unequal dc voltage sources and seven switches. The suggested topology creates just positive and zero voltage steps and it needs to one H-bridge to generate negative voltage levels. Based on the located H-bridge, two different cascaded multilevel topologies are proposed. Also, various methods to specify the magnitudes of dc voltage sources are suggested. The proposed cascaded multilevel inverters in comparison with the conventional cascaded topologies and other new topologies which presented in literature decrease the number of components such as, IGBTs, switches, driver circuits and DC links. PSCAD/EMTDC simulations results of 19-level inverter are presented to reconfirm the correct performance of the suggested topologies.