基于暂态波形相关性的配电网故障定位方法

配电网拓扑结构复杂、分支众多，利用单一故障特征的配电网故障定位方法大多存在可靠性差、定位精度低等不足，为此文中提出了一种基于暂态波形相关性的配电网故障定位新方法。配电线路发生故障后实时检测故障暂态波形，利用S变换构造时频矩阵，将其与各分支样本库中的时频矩阵进行相似度计算，并根据相似度的大小判定故障分支；然后根据同一分支不同位置故障时暂态波形的整体波幅差异来确定故障范围，并利用整体波幅偏差与故障位置的比例关系计算得到精确的故障位置。仿真分析表明，在不同的故障条件下，该方法均能可靠、准确地进行故障定位，有望提高配电网故障定位的准确度与可靠性。

Fault Location Method for Distribution Network Based on Transient Waveform Correlation

The distribution network topology is complex and has many branches. The fault location method of distribution network with only single fault characteristic mostly has the disadvantages of poor reliability and low positioning accuracy. Therefore, a new method for fault location of distribution networks based on transient waveform correlation is proposed.When a fault occurs on the distribution line, the fault transient waveforms are detected in real time and a time-frequency matrix is constructed by using S-transformation. Then the similarity between the constructed time-frequency matrix and the time-frequency matrix in each branch sample database is calculated and used to determine the fault branch. The fault range is determined according to the overall difference in the amplitude of the transient waveform when the fault is in different locations of the same branch, and the exact location of the fault is calculated by using the proportional relationship between the overall waveform amplitude deviation and the location of the fault. The simulation analysis shows that the proposed method can locate faults reliably and accurately under different fault conditions, which is expected to improve the accuracy and reliability of the fault location in the distribution network.