Open circuit fault-tolerant operation of 3-Φ multilevel inverter

Abstract

A modified Fault-Tolerant (FT) structure is presented for the five-level Multi-Level Inverter (MLI) in this research work. A self capacitor voltage balancing control regulates the voltage across the capacitor by a half magnitude of the DC source value to produce a five-level output voltage waveform. Furthermore, the self capacitor voltage balancing control reduces complexity and enhances system reliability. A possible Open Circuit (OC) fault in the switches of the proposed structure is further analyzed. On the basis of a comparative analysis between the five-level MLI and the proposed faulttolerant structure, this structure is presented. When compared with the most recent FT topologies, it contains fewer devices. MATLAB/Simulink are used to study the proposed single-phase and three-phase FT structures under pre-fault, fault and post-fault operation.