Transient Analysis of Converter Valve Before and After Blocking of MMC Conventer Station After Bipolar Short Circuit

Modular multilevel converter (MMC) is a new topology of voltage source converters. At present, the research on the flexible DC of this topology mainly focuses on the control strategy. The fault analysis and protection principle research is not complete enough, and it is necessary to analyze it in depth. The bipolar short circuit is the most serious fault type of the DC line. By analyzing the mechanism before and after the closing of the rectifier valve, the voltage and current transient voltages of the rectifier valve and the DC line are obtained, and a simulation model is built on the PSCAD to verify. (paper)