输电线路发生单相接地短路后采样周期对测距精度的影响

Influence of Sampling Period on the Accuracy of Single Phase to Ground Fault in Transmission Line

摘要: 本文分析了输电线路三相系统发生单相接地短路故障时工频测距的基本原理。选用PSCAD/EMTDC仿真软件搭建输电线路分布参数模型，针对输电线路发生单相接地短路故障进行仿真，使用傅立叶算法对故障周期进行提取并计算电压电流工频量，利用基于工频分量的单端故障测距原理进行故障测距。分析利用傅立叶算法在提取电压电流工频量时选取不同采样周期对测距精度的影响。借助福建霞浦小沙110 KV大京风电线发生单相接地短路故障时，录波器采集到的实时故障数据，验证采样周期对测距结果的影响。对利用工频量进行故障测距时采样周期的选取有一定的借鉴意义。

Abstract: We analyze the basic principle of power frequency fault location of single-phase to ground fault in three-phase system of transmission line and use PSCAD/EMTDC simulation software to build the transmission line distributed parameter model. According to the transmission line single-phase grounding short circuit fault simulation, we use the Fourier algorithm to extract cycles of failure and calculate the voltage and current of power frequency to fault location, which is based on power frequency component of single end fault distance measurement principle. And current power frequency is analyzed by using the Fourier algorithm. Based on the real time fault data collected by the recorder in the single phase to ground fault in the small sand 110 KV large Xiapu Fujian wind line, the influence of the sampling period on the ranging results is verified. It can be used for referencing in the selection of sampling period when using power frequency to carry out fault lo-cation.