小电流接地系统两相接地短路时功率方向元件动作分析  

Action Analysis of Power Direction Element under Two-phase Ground Short-circuit Fault of Low Current Grounding System

作　　者：徐辉 Xu Hui

机构地区：[1]中国石油华北石化公司,河北任丘062552

出　　处：《上海电气技术》2024年第1期25-28,101,共5页Journal of Shanghai Electric Technology

摘　　要：小电流接地系统指中性点不接地或通过大电感接地的系统,配电网通常采用小电流接地系统。在双电源配电网中,为判别故障方向,电流保护需要配置功率方向元件。针对保护安装处正方向出口两相接地短路故障和保护安装处正方向远端两相接地短路故障,详细分析了小电流接地系统发生两相接地短路故障时功率方向元件的动作行为,得出在典型的功率方向元件内角整定值情况下,小电流接地系统发生两相接地短路故障时,功率方向元件可以准确判别故障方向。The distribution system usually adopts the low current grounding system,that is,the neutral point of the system is not grounded or the grounding is through the large inductance.In the distribution system with double power source,power direction element is needed for current protection to identify the fault direction.Aiming at the two-phase ground short-circuit fault at the positive direction outlet of the protection installation and the two-phase ground short-circuit fault at the positive direction far end of the protection installation,the action behavior of the power direction element when the two-phase ground short-circuit fault occurs in the low current grounding system was analyzed in detail.It is concluded that the power directional element can accurately identify the fault direction when the two-phase ground short-circuit fault occurs in the low current grounding system under the typical internal angle setting value of power direction element.

关 键 词：小电流接地系统 短路 功率方向元件 动作 

分 类 号：TM713[电气工程—电力系统及自动化]