Fault detection on multilevel power converter based on mass center of the voltage pattern

Multilevel power converters are now used in many applications. This type of power converter is characterized by the increased likelihood of a switch failure due to the high number of switches. However, this also allows reconfiguring the power converter in order to work even under internal fault condition. This paper introduces a new approach to detected and identify a faulty switch. The proposed method uses the power converter output voltages and is based on mass center of the voltages patterns. This approach is illustrated on a five-level cascaded H-bridge inverter. From the obtained simulation and experimental results it is possible to confirm the applicability of the proposed approach.