JPH0572249A - Method for locating fault point of transmission line - Google Patents

Abstract

PURPOSE:To locate the distance up to a fault point by detecting two traveling waves generated by the fault of a transmission line to calculate the time lag between the times arriving at a detection point of two traveling waves. CONSTITUTION:A surge current wave and an acoustic wave respectively different in propagation time are detected by the surge current wave detection sensor 12 and acoustic wave detection sensor 14 provided to a transmission line 10. The detected surge current wave is transmitted to a time lag comparing circuit 18 by a surge wave detection circuit 16A and the acoustic wave is transmitted to the circuit 18 as an output signal by an acoustic wave detection circuit 16B. The time lag between the times arriving at a detection point of the surge current wave and the acoustic wave is detected by the time lag comparing circuit 18 and the distance up to a fault point is operated from the arrival time lag to be displayed.

Description

Detailed Description of the Invention

[0001]

The present invention relates to maintenance of overhead power transmission lines,
It relates to the method of locating the fault point of the transmission line at the time of inspection.

[0002]

2. Description of the Related Art Conventionally, in order to locate a fault point on an overhead power transmission line, as shown in FIG. 8, a current flowing through the ground line due to a ground fault or a short-circuit current at the time of distribution is distributed to the power transmission line and attached. The current distribution detected by these current transformers was collected, and the distribution of the currents detected by these current transformers was collected in a locator, and the section in which the accident occurred was identified from the magnitude and phase of the current.

[0003]

In this prior art transmission line fault location method, it is determined which of the sections divided by the distributed current transformers has an accident. It was possible, but it was not possible to determine where in the section the accident occurred. Therefore, it is necessary to inspect while checking the section where the accident has occurred, and since this section is usually a relatively long section of about 1 km to 2 km, there is a drawback that the work is time-consuming and time-consuming.

An object of the present invention is to provide a transmission line fault point locating method capable of avoiding the above-mentioned drawbacks, accurately locating a point where an accident has occurred, and simplifying maintenance and inspection of the transmission line. To provide.

[0005]

As one means for solving the above problems, the present invention detects two types of traveling waves having different propagation velocities, which are caused by an accident in a transmission line,
The present invention provides a method for locating a fault on a transmission line, which is characterized by locating an accident occurrence position on the transmission line from the time difference between the times when the two traveling waves reach the detection point.

As another means for solving the above problems, the present invention detects two traveling waves having different propagation velocities generated by an accident in a transmission line, and these two traveling waves reach a detection point. In the fault location method of the transmission line, which evaluates the occurrence position of the fault point of the transmission line from the time difference of time, the other traveling wave is detected on both sides of the detection position of one traveling wave of the two traveling waves, and the other traveling wave is detected. A method for locating a fault point of a transmission line, which method detects the direction of the fault point with respect to the detection point from the phase difference of the detection output of the traveling wave.

[0007]

When a ground fault or a short-circuit accident occurs in the power transmission line, a surge current wave and an acoustic wave due to a flash fault are generally generated and propagate in the electric wire on the power transmission line. In this case, since the surge current wave is an electric signal and the acoustic wave is an oscillating wave propagating on the electric wire, the propagation speeds of these two traveling waves are different. Therefore, when these two traveling waves are detected, a time difference Δt of arrival times of the two traveling waves to the detection point is observed. At this time, if the propagation velocity of the surge current wave is υ _A and the propagation velocity of the acoustic wave is υ _B , the distance L from the detection point to the accident point is L = (υ _A · υ _B ) Δt / (υ _A − υ _B ). Therefore, as in the present invention, when the propagation time difference Δt between the surge current wave and the acoustic wave is detected, the distance from the detection point to the accident point can be detected, so that the accident point of the power transmission line can be located.

Further, when the traveling wave of the other traveling wave is detected on both sides of the traveling wave detection position of one of the traveling waves, the phase difference of the traveling wave of the other traveling wave from the accident point detected by the time difference Δt to the detection point is detected. Since it is possible to know which direction the distance is to the left or right of the detection point, it becomes easier to locate the accident point.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings, an embodiment of the present invention will be described in detail. FIG. 1 schematically shows a state in which the orientation method of the present invention is carried out. Accident points are located by the method of the invention. In this embodiment, as shown in FIG. 1 and FIG. 2, a surge current wave detection sensor 12 and an acoustic wave detection sensor 14 attached to a part of the overhead power transmission line 10 cause the overhead power transmission line 10 to generate a A surge current wave and an acoustic wave propagating on the power transmission line 10 are detected. A coil is used as the surge current wave detection sensor 12, and an acoustic wave sensor 14 is used as the acoustic wave sensor 14.
For example, a microphone can be used.

The detection signal of the surge current wave detected by the surge current wave detection sensor 12 and the acoustic wave detection sensor 14
As shown in FIG. 3, the detection signal of the acoustic wave detected by the surge current wave detection circuit 16A and the acoustic wave detection circuit 1
The waveform is shaped by 6B and output as a detection output. In this case, the surge current wave and the acoustic wave are
Since the propagation velocities propagating over 0 are different, the surge current wave reaches the surge current wave detection sensor 12 and the acoustic wave reaches the acoustic wave detection sensor 14 between the time shown in FIG. Such a time difference Δt occurs. This time difference Δt is electrically connected to the surge current wave detection circuit 16A and the acoustic wave detection circuit 16B and is detected by the detection circuits 16A and 16B.
Time difference comparison circuit 18 for reading the detection signal output from
To detect. In this way, by detecting the time difference Δt, the surge current wave detection sensor 12 and the acoustic wave detection sensor 14 cause the accident point 20 of the power transmission line 10 shown in FIG.
The distance L to L = (υ _B (acoustic wave propagation velocity) · υ
_Since it can be guided by _A (propagation velocity of surge current wave) Δt / (υ _A −υ _B ), the position of the accident point 20 can be accurately evaluated.

As shown in FIG. 5, the distance L to the accident point 20 is set by attaching the surge current wave detection circuit 12 and the sound detection sensor 14 by means of the arithmetic display circuit 22 electrically connected to the time difference comparison circuit 18. By calculating and displaying in the vicinity of the overhead power transmission line 10 thus displayed, and the maintenance inspector confirming the distance L to the accident point 20 thus displayed,
Locate the accident point 20.

FIG. 6 calculates the distance L to the accident point 20.
Another means for displaying is shown, and in the embodiment of FIG. 6, information regarding the time difference Δt transmitted from the time difference comparison circuit 18 and electrically connected to the time difference comparison circuit 18 via the transmission device 20 and the communication circuit 22 is calculated. Central processing unit 24 to display
The central processing unit 24 may be installed in the hand of a maintenance person who is located at a location distant from the overhead power transmission line 10. In this case, since the position of the accident point 20 can be evaluated at a location away from the site, maintenance and inspection of the overhead power transmission line 10 are facilitated. In the illustrated embodiment, the calculation and the display of the distance L to the accident point 20 are both performed by the maintenance inspector. However, the calculation of the distance L is performed on the power transmission line 10 and the numerical value obtained as a result is calculated. It may be transmitted and displayed to the maintenance personnel. Further, the detection signals detected by the surge wave detection sensor 12 and the acoustic wave detection sensor 14 are directly
It may be transmitted to the maintenance inspector and the steps after the time difference comparison circuit 18 may be performed by the maintenance inspector.

Next, still another embodiment of the present invention is shown in FIG. 7, in which the surge current wave detection sensor 12 is used.
Two acoustic wave detection sensors 14 on the overhead transmission lines 10 on the left and right of the
A and 14B are attached, and one surge current wave and two acoustic waves generated due to an accident of the overhead power transmission line 10 are detected.
The two acoustic wave detection sensors are electrically connected to the phase comparison circuit 26 via the two acoustic wave detection circuits 16B, and the phase comparison circuit 26 detects the phase difference between the two detection outputs of the acoustic waves. To do. From the phase difference thus detected, it is detected which of the left and right directions the accident point 20 is with respect to the acoustic wave detection sensor 14, and the accident point 20 is located. This makes it possible to confirm not only the distance L from the surge current wave detection sensor 12 and the acoustic wave detection sensor 14 to the accident point 20 but also in which direction the distance L is. The accident point 20 can be located more accurately. Also, in this example,
As shown in FIG. 7, the distance L to the accident point 20 is obtained by electrically connecting the time difference comparison circuit 18 to the surge current wave detection circuit 16A and one acoustic wave detection circuit 14B.
To be measured. In the illustrated embodiment, the acoustic wave detection sensor 14 is provided to detect the phase difference between the acoustic waves, but two surge current wave detection sensors are provided to detect the phase difference between the surge current detection waves. The direction of the accident point 20 may be located.

[0014]

As described above, according to the present invention, the distance from the detection point to the accident point is detected by detecting the time difference between the arrival times of the two traveling waves generated by the transmission line accident to the detection point. Since the accident point can be accurately located, it is possible to confirm in which direction the accident point is with respect to the detection point from the phase difference between the two traveling waves. Therefore, the fault point of the transmission line can be located more easily and accurately, and the maintenance and inspection of the transmission line can be facilitated.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an implementation state of an accident point locating method of the present invention.

FIG. 2 is an enlarged view showing a mounting state of a detection sensor used in the method of the present invention.

FIG. 3 is an output system diagram of a detection sensor used in the method of the present invention.

FIG. 4 is a waveform diagram showing the outputs of two traveling waves detected by the method of the present invention.

FIG. 5 is a second output system diagram of the detection sensor used in the method of the present invention.

FIG. 6 is a third output system diagram of the detection sensor used in the method of the present invention.

FIG. 7 is a schematic system diagram showing an implementation state of a second embodiment of the present invention.

FIG. 8 is a schematic view showing an implementation state of a conventional accident point locating method.

[Explanation of symbols]

 10 Overhead Transmission Line 12 Surge Current Wave Detection Sensor 14 Acoustic Wave Detection Sensor 16A Surge Current Wave Detection Circuit 16B Acoustic Wave Detection Circuit 18 Time Difference Comparison Circuit 24 Central Processing Unit 26 Phase Comparison Circuit

Claims (2)

[Claims] 1. A position where an accident point on the power transmission line occurs based on a time difference between two types of traveling waves having different propagation velocities generated by an accident on the power transmission line and reaching the detection point. A fault location method for transmission lines, which is characterized by locating. 2. The traveling wave of the other traveling wave is detected at both sides of the traveling wave detection position of the two traveling waves, and the accident point is detected with respect to the detection point from the phase difference of the detection output of the other traveling wave. The method for locating a fault on a power transmission line according to claim 1, wherein the direction is detected.