Simulation Analysis of Overvoltage of Single Phase Grounding Fault in Paralleled 12-Pulse Rectifier System

Abstract

In order to solve the problem of overvoltage of single phase grounding fault of paralleled 12-pulse rectifier system, firstly the common mode wave problem of monopole in DC side at fault is analyzed. Secondly, the transient overvoltage of the system at the AC side single phase fault is analyzed by simplifying the charging and discharging circuit of capacitances on DC side. Finally, the theory of frequency extinguishing arc is used to simulate the intermittent arc grounding overvoltage. It is proved that the capacitance on DC side also affects the AC overvoltage in the system that provides a basis for the better suppression of overvoltage in the project. The correctness of the conclusion is verified by PSCAD/EMTDC simulation software in the analysis process.