小电流接地故障分界新技术

着重分析配电线路中不同区域发生小电流接地故障时，分界开关处的稳态故障特征以及各种工频分量分界方法，并提出一种新的分界方法——工频零序电压电流综合法。该方法综合利用分界开关处零序电压和零序电流的幅值与相位特征识别故障区域，判定结果不受消弧线圈补偿度、过渡电阻大小以及电压、电流互感器传变误差的影响，具有更高的准确性。此外，还解决了分界技术在实际应用中会遇到的若干问题，增强其实用性。

New Earth Fault Detection Technology for Automatic Boundary Switches in Non-Solidly Earthed Network

This paper focuses on analyzing the boundary switch＇s steady fauh characteristics and detection principle based on the fundamental frequency component when single phase to earth faults happen in different areas, and proposes a new synthesis method based on the fundamental frequency zero- sequence voltage and fundamental frequency zero-sequence current. This method uses both the amplitude and phase of the boundary switch＇s zero-sequence voltage and zero-sequence current to determine the fault＇s location, and has a higher accuracy because the are suppression coil compensation degree, the value of transient resistance and the errors of voltage and current transformer have no effect on the results. In addition, the paper has solved some problems in the practical use of these methods, thus increasing applicability of these methods.