三相可控整流器故障波形仿真研究

In the high-power controlled rectifier, the device which is most likely to damage is power devices (such as the thyristors). So, fault detection and diagnosis of the rectifier device is essential, but first of all we must study the rectifier fault waveforms. In this paper, based on a flat background of mine hoist system, the MATLAB is used to build a thyristor converter - DC motor speed control system to simulate the process of hoist extracting. Speed control mode is the speed, dual-closed loop DC current mode. Three-phase bridge circuit of Rectifier is used as the main circuit. 8 categories of failure are concluded and the fault voltage and current waveforms are given, fault waveform characteristics are analyzed. Sustained fault operation and sudden failure is distinguished .The fault waveforms of two states are compared, thus the transition process of a sudden failure voltage waveform is found, which can be used to determine the failure moment. Finally, Summary and Outlook is made.