10 kV配电线路单相接地故障暂态特征分析

The Analysis of the Performance of the Transient Current in the Single-Phase-Grounded 10 kV Distribution Network

摘要: 配电网作为我国电力系统的重要组成部分，其安全稳定的运行对整个电力系统的安全稳定运行起着重要的作用。在我国，配电系统主要采用中性点不接地系统。在中性点不接地系统中发生单相接地故障后，故障电流比较小，系统可以继续正常运行一段时间，不影响对用户供电。但是，长时间的运行会引起其它更严重的故障，破坏系统的安全运行。因此，必须及时找到故障线路并且切除。而应用故障线路暂态信息进行选线是目前研究的热点，本文在分析国内外10 kV配网单相接地故障原因及危害的基础上，分析了10 kV配网发生单相接地故障时系统暂态电流的变化规律。

Abstract: As one of the important composed parts of power system, the distribution network’s stable and safe operation plays a pivotal role at the security and stability of the entire power system operation. Isolated neutral networks are mainly used in our distribution system. When the single-phase earth fault occurs in the isolated neutral networks, the fault current is relatively small. It makes no effects on the normal operation in a period of time. Although the faulted line does not need to be eliminated immediately after ground fault, long period of fault status is dangerous to the safety of the systems. Therefore, the fault line must be identified in time and removed. Recently, it is re-search hotspots using the transient information of fault line to realize fault circuit selection. First, this paper analyzes the cause and harmfulness of the single-phase-grounded fault of 10 kV distri-bution network system. Then, the performance of the transient current in the single-phase- grounded 10 kV distribution network is analyzed in this paper.