A Multilevel Inverter Topology With an Improved Reliability and a Reduced Number of Components

Abstract

The reliabilities of the renewable energy source systems are affected by their inverter structures. So, an inverter topology with higher reliability reduces the maintenance cost of the system. In this article, a multilevel inverter structure is proposed with improved reliability and reduced component count. The proposed structure produces 7 and 11 voltage levels in symmetrical and asymmetrical configurations, respectively. This inverter topology utilizes six unidirectional switches and one bidirectional switch. The proposed inverter structure can be extended to generate any number of voltage levels with the inherent property of producing both positive and negative voltage levels. Various comparisons including the total number of switches, the total number of switch drivers, and the total blocking voltage are done to show the effectiveness of the proposed structure in the reduction of the component counts. In addition, the reliability of the proposed structure is analyzed and comparisons with other counterpart structures are studied. The comparison results show the reliability improvement of the proposed inverter structure. Finally, the simulation results, extracted by MATLAB/Simulink, and the experimental results, obtained from a laboratory prototype, are provided to prove the feasibility of the proposed multilevel inverter (PMI) structure.