A Boat Type Fault Tolerant Multilevel Inverter Topology Resilient to Switch Fault

Ensuring the reliability of multilevel inverters (MLIs) is a significant focal point in numerous sensitive industrial applications. In a conventional MLI, an abnormal situation arises when a fault occurs within any of the switches. Consequently, the other components may suffer severe damage. In such a situation, the faulty inverter must be removed. Thus, this work presents a new fault tolerant MLI (FT MLI) topology, which incorporates more redundant switching states in comparison to normal MLIs. As a result, the proposed FT MLI topology is resilient to open-circuit faults in the switches. An explanation of the operation of the proposed topology is provided, accompanied by a description of the FT capabilities for symmetric mode as well as asymmetric mode. The proposed topology has per unit total standing voltage of 6.33 and 6.5 for symmetric and asymmetric modes of operation, respectively. Simulation results using MATLAB/Simulink and real-time results using Typhoon hardware-in-the-loop (HIL)-402 device are presented to demonstrate the FT MLI topology's effectiveness. This paper compares the proposed topology with other FT MLI topologies, emphasizing the advantages of the proposed topology.