Fault Detection Algorithm for Three-Level DC–DC Converter in a Photovoltaic System

This paper presents an open-switch fault detection algorithm for a three-level DC–DC boost converter in a photovoltaic system. Three-level DC–DC converter and its various derivatives are popular topologies in high-voltage, high-power converter applications. To ensure service continuity, a reliable fault diagnostic algorithm and a fault tolerant strategy are strongly mandatory. The fault diagnostic method does not necessitate any additional sensors and relies on the input current waveform and the necessary control variables for maximum power point tracking. The fault tolerant strategy is realized by including redundant switches to the converter to assurance continuity of service. The proposed fault detection algorithm is validated under different scenarios by the obtained results.