贵州电网小电流选线装置的运行现状及建议

Study on operating status of small current line and selection devices in Guizhou Power Grid

目前贵州电网的小电流选线装置选线准确率低，误选拒选概率大，主要原因是大部分选线装置采用基于稳态工频信号的选线原理，该选线原理易受过渡电阻、互感器精度问题以及其它一些因素影响，导致故障线路与非故障线路之间的差别变小，影响选线效果。

Alignment accuracy of small current grounding line devices in Guizhou grid is low, and probability of false selection and refu-sing selection is large. It is mainly because of the most line selection devices using selection principle based on steady - state power fre-quency signal. The principle is easily affected by the transition resistance, mutual inductor accuracy and other factors, which led to the difference between fault line and non -fault line smaller, and then affected alignment result.