A new fault-tolerant converter for renewable energy applications with improved reliability

With power converters consisting of several components, the reliability of a power converter becomes a major concern. With a switched-capacitor (SC) integrated into multilevel inverter (MLI) topologies, the chances of faults is more due to a much larger number of components than the MLI topologies with multiple isolated dc voltage sources. In this article, several SC-based 5L-MLI topologies have been analyzed for their performance with open-circuit fault (OCF), and based on the analysis, three 5L fault-tolerant MLI topologies have been proposed. The analysis for the proposed topologies have been carried out in terms of power loss analysis using PLECS software and power quality analysis using MATLAB software for different fault case scenarios. Further, the proposed 5L topologies have been compared with a similar state-of-the-art. A hardware prototype has been developed, and results have been discussed for various operating conditions.