A Complete Fault-Tolerant Solution for A Single-Phase Five-Level Hybrid Flying Capacitor Inverter

Abstract

Inverters generally experience the problem of switch failures, whether it is open circuit or short circuit. Hence topologies which can withstand these type of fault scenarios are gaining importance. Therefore, in this paper, a fault-tolerant solution is proposed for a five-level hybrid flying capacitor inverter. This inverter can withstand both open circuit and short circuit faults and additionally, the flying capacitor is always balanced. The inverter is studied for fault in both the legs and a complete fault solution is proposed by addition of a few switches. The DC source and other components such as switches and capacitors requirement for the same number of level generation are also reduced with the proposed topology when compared to existing ones. An advantage of the topology is that it can maintain the same number of levels for flying capacitor leg in case of a fault. The proposed topology is implemented in MATLAB/SIMULINK environment and the results for R-L load is shown for faults in both the legs of the inverter. A fault is created at a particular point of time and pre-fault, fault and post-fault scenarios are studied with the help of simulation results. The results strongly validate the satisfactory operation of the proposed inverter in all three cases.