New 8-level basic structure for cascaded multilevel inverters with reduced number of switches and DC voltage sources

Multilevel inverters are generally used in medium-voltage and high-power applications. In this paper, a new 8-level basic structure for cascaded multilevel inverters is proposed. Based on proposed basic structure, two different cascaded multilevel topologies are proposed. The proposed cascaded multilevel inverters use less number of power switches, IGBTs and dc voltage sources compared with the conventional multilevel inverters. In order to generate all steps at the output voltage, three different algorithms to determine the amplitudes of dc voltage sources are presented. To reconfirm the performance and correct operation of the proposed topologies, the experimental results for a 15-level inverter are presented.