基于配网数据的10 kV线路接地故障精确定位的研究

Research on Accurate Location of Ground Faults in 10 kV Lines Based on Distribution Network Data

针对目前主流的接地选线原理,存在高阻接地、无法具体到线路的哪一段接地,从而造成对接地线路进行全线查找,浪费了大量的人力物力的问题,介绍利用依托配网大数据进行配网接地查找的方式,不仅仅能够准确的定位到线路,而且可以定位到线路的区段或者支线上,将大大地提高配网接地故障查找的准确度和精确度。针对采用此方法判断配网线路接地,存在死区、存在低压侧电压不能反映高压侧接地等问题,一一提出有针对性的解决方法,依托配网大数据进行配网接地查找的方法,是一种新的接地故障查找的方法,从原理上弥补了变电站端小电流接地选线装置的不足,可以与小电流接地选线装置配合,达到100%的选线正确并定位。

For a long time,When single-phase ground fault in the distribution network dominated by 10 kV("distribu‐tion network"refers to 10 kV distribution network).Since 10 kV distribution network is a small current grounding sys‐tem in which the neutral point is not grounded or grounded via the arc suppression coil.Judging the ground fault line by the zero sequence current,voltage or harmonics observed at the side of the substation is the mainstream ground fault se‐lection principle at present.There are two main problems in this method:one is the existence of high resistance ground fault,which makes it impossible to achieve 100%correct rate of line selection;the other is that it is impossible to speci‐fy which section of the line is grounded.As a result,the ground fault lines are searched in line and wasted a lot of man‐power and material resources.The judgment of ground fault line based on the observed electrical capacity of substation is based on the view of main network.But the ground fault is on the distribution network.Therefore,we should use the vision and resources of the distribution network to find the ground fault of the distribution network.That is to rely on distribution network big data for the search of the distribution network grounding fault,and even precise positioning.This article will explore this.