基于新型配电自动化开关的馈线单相接地故障区段定位和隔离方法

针对配电网馈线单相接地故障定位隔离问题，提出采用具有测量和远程通信功能的新型配电自动化开关构成分布式馈线自动化系统，通过监测一条馈线上各开关处的零序电流和零序电压，计算由区段的各端点流入该区段的零序电流的相量和(即流入区段零序电流)，以识别故障区段，判断此馈线故障状态，实现对故障区段的快速隔离的新原理。文中亦简要介绍了新型配电自动化开关的特性。此故障定位方法适用于各种中性点接地系统s理论上不受接地点过渡电阻的影响。Matlab仿真结果证明原理分析正确，此故障定位方法具有实用价值。

A NEW METHOD OF LOCATING AND ISOLATION FOR SINGLE PHASE GROUNDING FAULT SECTION OF FEEDERS IN POWER DISTRIBUTION NETWORK BASED ON NEW TYPES OF DISTRIBUTION AUTOMATION SWITCHGEAR

To solve the problem of locating and isolating single phase grounding fault section of feeders in power distribution networks, single phase grounding faults in ineffectively grounded systems are analyzed, the results indicate the zero sequence current draining into the fault section (the vector sum of zero sequence current draining into the section from its knots) nearly equal to the zero sequence current draining into the fault spot while the zero sequence current draining into the sound section equal to capacitive current of this section. According to the analysis, a new method of locating single phase grounding fault sections is proposed. In this method the fault section of a feeder is located by inspecting the ratio of the maxim amplitude value of the zero sequence current draining into the every section of the feeder to the average amplitude value of that draining in the other sections and the phase difference between the maxim zero sequence current draining into every section of the feeder and the zero sequence voltage. If the qualification is fulfilled, the feeder is the fault feeder and the section corresponding to the maxim zero sequence current is the fault section. Results of simulations testify that the method is applicable in all types of ineffectively grounding systems and is independent of transition reactance.