基于泄漏电流的高压电缆线路故障测距方法

为实现高压电缆线路短路故障发生后准确故障定位,提出一种利用故障通道泄漏电流的离线故障测距方法。该方法在短路故障发生后于电缆终端加直流电压,泄漏电流主要通过故障击穿通道沿金属护层流入两端接地点,在线路两端接地点检测护层电压,通过单位长度金属护层阻抗与泄漏电流和护层电压的关系,可计算出故障点位置。仿真结果表明,该方法能够有效的定位故障点位置,其相对误差不超过8%,绝对误差不超过50 m。

High voltage cable fault location method based on leakage current

In order to realize the accurate fault location after short-circuit fault of high voltage cable,this paper presents an offline fault location method via fault channel leakage current.The method firstly adds a DC voltage to the cable termination after a short circuit fault occurs.The leakage current mainly flows through the fault breakdown channel along the metal sheath to the grounding point at both ends.The sheath voltage can be detected at the grounding point at both ends of the circuit,and the fault position can be calculated by the relationship between the impedance of the metal sheath of the unit length and the leakage current and the sheath voltage.The simulation results show that the method can effectively locate the fault point,and its relative error is no more than 8%,and the absolute error is no more than 50 meters.