一种基于时间轴整定的T型混合输电线路故障测距方法

为解决带T型分支的多段式架空线-电缆混合输电线路故障测距问题,提出了一种基于时间轴整定的T型混合线路故障测距方法。首先,根据三个假定的端点故障位置整定出以线路任意两端时间差为基准的三个时间轴,使得在线路任意一点发生故障时总能在其中两个时间轴中找到对应点;其次,以线路三端得到的三个时间差在对应时间轴中的位置作为故障区段判据,三个判据可保证判断故障区段的准确性;最后,根据时间轴中各点与线路长度间的线性关系得出以两个时间轴为基准的两个测距结果,并将测距结果取平均值。算例仿真结果表明,所提方法正确可行、原理简单,适用于各种带T型分支的混合输电线路结构,且不受过渡电阻的影响。

A Fault Location Method for T-Type Hybrid Transmission Line Based on Time Axis Setting

To solve the problem of fault location of multi-segment overhead line and cable hybrid transmission line with T-type branch, a new fault location method for T-type hybrid line is proposed based on time axis setting. Firstly, three time axes based on the time difference between any two ends of the line are determined according to the three assumed fault locations, so that the corresponding points can always be found in the two time axes when the fault occurs at any point of the line. Secondly, the position of the three time differences at the three ends of the line in the corresponding time axis is taken as the fault section criterion, and the accuracy of the fault section can be guaranteed by the three criteria. Finally, according to the linear relationship between the points in the time axis and the length of the line, two ranging results are obtained based on two time axes, and the ranging results are averaged. The proposed method is simple and applicable to all kinds of hybrid transmission lines with T-type branches. The simulation result shows that the method is correct and feasible, and is not affected by the transition resistance.