基于相电流有效能量循迹法的配电网单相故障定位

Fault Location Method for Single-phase Grounding Fault in Distribution Network Based on Trajectory of Phase Current Valid Energy

配电网单相故障定位问题一直是研究热点与难点之一。文中针对放射状配电网,首先理论分析了单相故障情形下故障相电流高频暂态分量呈现出的一般性分布特点,找出了该分量在配电网中的主要流通路径;进而借助小波变换定义并提取了各馈线首端测量相电流的暂态有效能量,并设计了基于有效能量循迹法的单相接地故障定位判据;最后基于PSCAD/EMTDC平台搭建了某地区实际配电网模型,仿真测试并验证了定位判据在不同故障严重程度、过渡电阻、中性点接地方式及配电网参数等工况下的适应性。

The fault location in the neutral un-effective grounding system has long been a hot issue.The universal distribution characteristics of the high-frequency transient component in the faulty phase current are firstly analyzed,based on which the main path of the high-frequency energy is defined and studied.Then,the valid high-frequency energy for each measuring point at head of feeder is extracted by means of wavelet transform,and the fault identification method based on the trajectory of faulty phase valid energy is finally put forward and assessed.Based on PSCAD/EMTDC platform,a real distribution network in Jiangxi Province is established,and the performance of proposed method under different fault conditions,fault resistances,neutral grounding modes and system parameters are verified.