基于FTU的闭式配电网故障测距研究

Research of Fault Location Based on FTU for Closed Distribution Network

为解决闭式配电网多电源交叉支路单相接地故障的准确测距难题,提出了利用与故障支路相邻的多端FTU信息的故障测距方法。该方法基于图论理论形成配电网拓扑结构的故障信息矩阵,得到交叉区段的故障判据,解决故障定段的误判问题,实现故障区段快速准确判定;利用两端电源接地回路有向图拓扑结构的电路特性,抵消故障点接地电阻对故障测距的影响,提高故障定位的准确性。该方法充分利用现有的FTU设备,不需要额外增加辅助设备投资,排除了其引入环节带来的误差,能够适用于复杂配电网络。利用11节点配电网络对提出的方法进行仿真,验证了该方法的有效性和准确性。

In order to solve the problem of accurate fault location of single-phase ground fault in the closed distribution network with multiple power and cross branch, the fault location method based on the information from the multi-terminal FTU that is adjacent to the fault branch is proposed. The method is based on the theory of graph theory to form the fault information matrix of the distribution network topology that gets the fault criterion of the cross branch to solve the problem of false judgement in fault location. The fault section can be quickly and accurately determined in the complex network. According to the circuit characteristics of the directed graph topological structure of the ground loop of both ends of power, the effect of the grounding resistance at fault point on fault location can be neutralized, therefore the accuracy of fault location would be improved. This method takes full advantage of the existing FTU equipment, so there is no need to increase additional equipment investment, additionally, it can eliminate the error caused by other introduced links and be applied to complex distribution network. The proposed method is simulated by 11 node distribution network,and the validity and accuracy of the method are verified.