A novel three phase 7-level asymmetrical multilevel inverter with reduced number of power electronic switches

Abstract

In the modern set up of generation, transmission, distribution and electric power utilization, dc to ac power conversion is a very important technology and multilevel inverter are the best choice for this converion as it has many advantages over two level inverter. In this paper, a new asymmetrical multilevel inverter topology for 7-level inverter is proposed which requires less number of switches, driver circuits and dc voltage sources as compared to other asymmetrical topologies and conventional multilevel inverter topologies. In the proposed topology, six power electronic switches and two dc voltage sources are required for generating 7-level in single phase output voltage. Performance of the proposed topology to generate positive, zero and negative level have been evaluated in terms of Total Harmonic Distortion (THD) in the output voltage using simulation in MATLAB environment. To validate the performance of proposed topology various waveforms and simulation results are presented in the paper. Fundamental switching control technique is used to operate the various switches.