多级多分支配电线路雷击故障定位方法

A Method for Locating Lightning Strike Faults in Multi-level and Multi-branch Distribution Lines

针对监测终端受多级多分支配电线路负荷小,无法布置在线路末端导致监测范围小的问题,以及雷击次级分支时缺乏有效识别方法的现状,提出一种适用于多级多分支配电线路的雷击故障定位方法。首先通过电流极性判断矩阵识别监测区段内外故障,并针对区段外故障采用改进型双端行波定位方法进行故障定位。然后,针对监测区段内故障,基于改进型双端行波原理形成故障支路判断矩阵实现一级多分支线路的故障定位,而针对多级多分支线路,需要先采用矩阵变换将多级多分支变换为一级多分支线路。最后,PSCAD/EMTDC仿真结果表明,该方法可以有效定位监测区段外故障,并能有效定位多级多分支配电线路中次级线路雷击故障,扩大分布式监测系统的监测范围,对于示范线路目前的布点方案,将监测范围扩大了57.46%。

A lightning fault location method suitable for multi-level and multi-branch distribution lines is proposed to address the issue of small monitoring range caused by the low load of monitoring terminals on multi-level and multi-branch distribution lines,which cannot be arranged at the end of the line,and the lack of effective identification methods when lightning strikes secondary branches.Firstly,the fault location outside the monitoring section is completed through polarity judgment matrix and improved dual terminal traveling wave positioning.If the fault location is determined to be within the section,a fault location judgment matrix is formed based on the improved dual terminal traveling wave principle and combined with matrix transformation method to propose reasonable criteria for locating faults within the section.Finally,the PSCAD/EMTDC simulation results show that this method can effectively locate faults outside the monitoring terminal section and locate secondary line lightning strikes in multi-level and multi-branch distribution lines,effectively expanding the monitoring range of the monitoring system.For the current layout plan of the demonstration line,the monitoring range has been expanded by 57.46%.