A Novel Short-Circuit Fault Diagnosis Method for Three-Phase Current Source Converter

In order to improve the reliability of current source converters, a new fault diagnosis method that can identify the single-switch and double-switch short-circuit faults is proposed in this article. It only needs an output current signal. First, the amplitude and phase of the output current vector are calculated in a real-time manner. Second, the amplitude is compared with a diagnosis threshold. Combined with the phase information, the switch that has a short-circuit fault can be detected and located. The method is simple to achieve, which can be implemented in the existing control program directly. No additional sensors or other auxiliary equipment are needed. Compared with the existing fault diagnosis methods, the detection speed is faster and the implementation is simpler. Experimental results are presented to verify the effectiveness of the proposed solution.