基于谐波的电力电缆单相接地故障在线测距方法研究

Research on Single-phase Ground Fault On-line Location Method of Power Cable Based on Harmonics

提出一种适用于电力电缆发生单相接地故障的在线故障测距方法。当电力电缆发生单相电弧性接地故障时,线路测端中存在以基波和三次谐波为主的电气分量。通过分析发生故障时各序网络的等效电路,列出各次谐波下对应电路的方程。利用在线检测出线路测端电压和电流的基波和三次谐波分量作为方程组的已知量,求解方程组得到故障距离和电弧电压。ATP-EMTP仿真验证该方法精确度高,可为电力电缆故障在线故障测距提供一种简单实用的方法。

Propose a on-line fault location method which is suitable to the single phase grounding fault of power cable. When the power cable occurs single-phase arc grounding fault, the measurable end of the line contains mainly fundamental and third harmonic, By analyzing the failure of the equivalent circuit of the sequence network, Listed r each harmonic equation of the circuit corresponding to each harmonic, using the on-line measurable fundamental and third harmonic of voltage and current as the known amount of Equations, Solving equations to get the fault distance and arc voltage. The experiments through ATP-EMTP proves accuracy of the method, provides a simple and practical way for power cable on-line fault location.