Failure simulation and protection strategy of mid-voltage three-level frequency converter

Because of the complexity of topology and control strategy, the mid-voltage and large power frequency converter has more failure types and fault feature relatively. Then the correct identification and isolation of its internal faults are very important. Based on the MATLAB/Simulink, this paper established a complete fault simulation model of IGCT series mid-voltage & mid-power three level frequency converter. With the model we simulated the fault condition and analyzed the features of each fault. And the complete protection strategy was designed. The validity and efficiency of the protection strategy were verified.