平行线路对线路零序保护影响的研究

Research on the Behavior of Zero Sequence Protection of Parallel Transmission Line

针对由于线路平行走线而产生的对线路零序保护的影响进行了分析。利用RTDS仿真系统建立了平行线路故障分析模型,仿真计算了在不同线路间距、不同平行长度的情况下,相邻线路发生接地故障时对本线零序保护的影响。仿真结果表明,相邻线路发生接地故障时,本线零序方向元件均满足正方向动作条件,所产生的感应电压、电流的大小与线路间距、平行走线长度有关,间距越小、平行长度越长,感应电压、电流越大。

In order to analyze the influence of the parallel transmission line to zero sequence protection,a RTDS simulation system is build,parallel transmission lines with different spacing and different length being considered.The simulation results show that when there is adjacent line ground fault,all the on-line zero-sequence directional relays will meet the conditions for positive direction.The induced voltage and current varies with the spacing and the length of parallel lines,i.e.,the smaller the line spacing and the longer the parallel lines,the larger the induced zero sequence voltage and current.