“3·21”天广直流线路高阻抗接地故障的分析与仿真

Analysis and simulation on '3·21' high impedance earth fault of Tian-Guang HVDC project

介绍了天广(天生桥—广东)直流线路保护的构成及基本原理。以“3.21”天广直流线路故障为例,根据实录波形和事件顺序记录(SER)信息,对直流线路发生高阻抗接地故障时直流线路保护的动作行为进行了深入分析。同时利用与实际控制保护系统基本相同的EMTDC直流仿真模型对该次线路故障进行了仿真研究,得到的仿真曲线与现场故障录波基本一致,证明EMTDC是分析直流实际故障的一种有效可靠的分析工具。

The structure and theory of the DC line protection in Tian-Guang （Tianshengqiao-Guangdong） HVDC project are introduced in this paper, With the example of high impedance ground fault which happened on the pole 2 of Tian-Guang HVDC project on March 21. 2005, according to the fault recordings and the sequence of events recording （SER） messages. the behavior of DC line protection during a high impedance earth fault is analyzed in detail. At the same time. the fault is simulated and studied by use of thc HVDC simulation model of EMTDC that is basically identical with actual control and protection system. The simulation results are almost the same as thc fault recordings, which proves that EMTDC is a reliable and effective tool to analyze actual faults in HVDC system.