Method of detecting earth leaking point without interrupting a power supply

Abstract

A method for detecting an electric leakage point without interrupting a power supply is provided. The method includes transmitting a unipolar direct current (DC) survey voltage signal to an electric wire of the power supply. The method includes transmitting a chain of electromagnetic wave signals generated around the electric wire to synchronize a reference time to measure an earth potential of the unipolar DC voltage signal and capture an electromagnetic tracking signal. The method includes tracing a buried route of the electric wire by analyzing the electromagnetic tracking signal according to the reference time. The method includes measuring the earth potential of the unipolar DC voltage signal on the ground according to the reference time. The method includes locating the electric leakage point by identifying a polarity of the unipolar DC voltage signal.

What is claimed is: 
     
         1 . A leakage point detection method for detecting a leakage point in a suspected earth leakage area in which an earth potential is increased by a commercial AC voltage, the method comprising:
 connecting a DC survey current signal transmitter to a power line installed in the suspected earth leakage area, wherein the DC survey current signal transmitter creates a DC survey current signal in the power line;   detecting a buried path of the power line by receiving a magnetic field signal generated by the DC survey current signal from a ground surface through a leakage detection device;   moving the leakage detection device along the buried path of the power line, wherein the leakage detection device has a plurality of wheel electrodes to measure the earth potential in front, back, left and right directions between the plurality of wheel electrodes contacting the ground surface;   finding a ground potential balance point where earth potentials between the plurality of electrodes in all directions are in the most equilibrium state after passing a location with a sudden increase of an earth potential value;   determining the ground potential balance point as the suspected earth leakage area   connecting a DC survey current voltage signal transmitter to a the power line;   synchronizing a transmitting time and a measuring time of the DC survey voltage signal transmitter and the DC survey current signal transmitter;   measuring the DC survey voltage signal on the ground surface at the measuring time recognized by the DC survey current signal at the ground potential balance point;   verifying that a location where a maximum value of the DC survey voltage signal is detected coincides with a location that has been determined as the ground potential balance point; and   determining a location as an earth leaking point where the ground potential balance point is the same location of the maximum value of the DC survey voltage signal.   
     
     
         2 . The leakage point detection method according to  claim 1 , further comprising:
 analyzing information contained in the DC survey voltage signal to identify a leakage source.