Design and Simulation of Asymmetric Multilevel Inverter by Modifying the Switching Method and Reducing the Number of Components to Compensate the Circulating Current

Abstract

In recent years, application of electronic power devices, especially electronic power converters has increased. One of these converters is symmetric and asymmetric modular multilevel converters that have many applications in the field of FACTS and HVDC and are classified as high power converters. In this study, an asymmetric modular converter is designed and controlled by using a new generalized algorithmic structure. In contrast to symmetric converters, the proposed structure with the same number of modules generates greater output voltage and subsequently it can reduce cost. It should be noted that a new method can control the circulating current. The second harmonic amplitude was reduced by about 50% during the phase circulation, and with circulating current THD in phases A, B and C was 4.02%, 10.61% and 12.39%, respectively.