JPS6340871A - Fault point probe system for distribution line - Google Patents

Abstract

PURPOSE:To accurately measure a distance, by applying voltage to both ends of a section and using the difference between line resistances. CONSTITUTION:Voltage E is applied to one end A of a fault section 1 from a voltage detector 2a and a current Ia is measured by an ammeter 3a. Then, voltage E is applied to said section 1 from the other end B thereof to measure a current Ib. Along with the value of the resistance (r) per the predetermined length of a distribution line, the value of the distance (x) from one end A to a fault point 4 and the value of the distance l-x from the other end B, the currents Ia, Ib are digitally converted by an A/D converter to obtain values which are, in turn, inputted to an operation circuit. Said values are operated according to a program preliminarily stored to calculate the distance (x). By this simple operation, a distance can be measured accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fault point deep investigation method for a power distribution line for investigating the fault point of a ground fault in a high-voltage distribution line.

[Conventional technology]

Fig. 4 is a circuit diagram showing a conventional fault point investigation method for power distribution lines.
HagAil! This consists of a DC power supply 8 and a switch 9. 4 is the fault point of the distribution line 7, 5 is the resistance of the fault point 4,
6as6b is the front and rear sides of the loop-shaped antenna 60 that is moved along the power distribution line 7.Next, the operation will be explained. First, a voltage pulse of a predetermined level is applied from one end A of the fault section 1 of the high-voltage power distribution line 7 from the charger 2 by opening and closing the switch 9 . By applying this voltage pulse, current flows from the fault point 4 to the ground via the resistor 5. The current flow at this time is electromagnetically induced into the antenna 6 and received. Then, when the front side 6a of the antenna 6 is in front of the accident point 4 and when the rear side 6b is behind the accident point 4, when viewed from the pulse application point and one end A of the accident section l, reception is possible. Since the directions of the currents are different, by determining these different states, the accident point 4 can be located simply by moving the antenna 6 along the distribution line 7.

[Problem that the invention seeks to solve]

Since the conventional fault point deep investigation method for power distribution lines is configured as described above, in order to locate the fault point 4, an ammeter is used to measure the positions where the current flowing in the front and rear sides 6a and 6b of the antenna 6 differs in direction. It is necessary to constantly monitor and confirm the following.
In order to carry out such confirmation incorrectly, there are problems such as the failure point cannot be reliably detected unless the current is measured repeatedly.

This invention was made to solve the above-mentioned problems, and by locating the distance based on the difference in track resistance from both ends of the accident section to the accident point, automatic calculation can be used to accurately and quickly detect accidents. The purpose of this study is to obtain a method for deep investigation of fault points in power distribution lines that enables point exploration.

[Means for solving problems]

The fault point deep investigation method of a distribution line according to the present invention applies voltage from one end and the other end of a fault section of a high-voltage distribution line by a charger, and at the same time applies voltage from each end of the fault section to the fault point. Based on the difference in line resistance, the distance to the accident point is determined by electrical calculation.

[For production]

Distribution line fault point detection in this invention is arranged! When a voltage is applied from one end of the fault section of the line to the other end by a voltage generator, the distance to the fault point is determined based on the value of the current flowing through the line resistance from each end to the fault point according to a predetermined electrical calculation formula. Make sure to do the following.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, 1 is the accident section of the high-voltage distribution line, 2a, 2°b
3a is a power supply device having a direct current source 8 and a switch 9;
e3b is an ammeter, 4 is a fault point, and 5 is a resistance at the fault point.

In addition, Figure 2 is a block connection diagram of a system that calculates the distance to accident point X.
22 is an analog-to-digital converter that digitally converts the currents Ia and Ib measured by the ammeters 3ae3b; This is an arithmetic circuit that calculates the distance X to the accident point based on the distance t of the accident section and the distance t of the accident section.

Next, the operation will be specifically explained according to the flowchart shown in FIG.

υ voltage E is applied to the voltage generator 2a from one end A of the fault section 1 of the high-voltage distribution line, and the current Ia at that time is measured with the ammeter 3a.

Next, the same voltage E as above is applied from the other end B of the fault section 1 from the voltage applying device 2b, and the current Ib at that time is measured by the ammeter 3b.
Measure with.

Here, the resistance of the distribution line with a predetermined length is r, the distance from one end A to the fault point 4 is X, the distance from the other end B to the fault point 4 is t-x, and the resistance 5 of the fault point is Rg. Then, Ib=□ ......(2) r(j-x)
+Rg, these Ia and Ib are digitally converted by the analog/digital converter 21, and these Ia,
Ib is connected to the arithmetic circuit 2 along with the above r e
2 (step Is). In this arithmetic circuit 22, Rg in equation (2) is substituted for Rg in equation (1), and (3)
The formula is calculated (step 2S).

E(Ib-Ia)+I a I b r LX=□
Song...(3) IaIbr This is K), the distance X from point A at one end of accident section 1 to accident point 4 is calculated and output and displayed on a predetermined display device (
Step 3S). That is, based on the current value flowing through the line resistance from each end of the accident section l to the accident point 4, the distance
can be determined extremely easily and accurately.

In addition, in the above embodiment, the case where the voltage of the chargers 2a and 2b is direct current was described, but low frequency alternating current may also be used.
The same effects as in the above embodiment can be obtained.

Further, in the embodiment described above, the power supply devices 2ay2b of the same voltage are provided, but if the accident classification is short, it is possible to make do with one device, and the same effect can be obtained in this case as well.

〔Effect of the invention〕

As described above, according to the present invention, the distance of the accident point can be determined by measuring the current value when electricity is applied from both ends of the accident section of the high-voltage distribution line and adding appropriate arithmetic processing to the measured value. This has the effect of allowing you to perform simple tasks with high precision.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing a fault point deep investigation method for distribution lines according to the present invention, Fig. 2 is a block connection diagram of a system for determining the distance to a fault point, and Fig. 3 shows the calculation processing in the system of Fig. 2. The flowchart, FIG. 4, is a circuit diagram showing a conventional fault point investigation method for power distribution lines. 1 is the fault section of the high voltage distribution line % 2 a # 2 b is the charger, 3 ae 3 b is the ammeter, 4 is the fault point, and 5 is the resistance at the fault point. In addition, in the figures, the same reference numerals indicate the same or equivalent parts. Figure 1 Figure 2 Table X

Claims (1)

[Claims] In the distribution line fault deep investigation method, which investigates the fault point of a ground fault in a high-voltage distribution line by using a current flowing from a power supply device to the ground through the fault point, the fault point of the distribution line where the above-mentioned ground fault occurred is investigated. A voltage is applied to each end of the accident section by the voltage applying device, and the distance to the accident point is determined based on the difference in line resistance from each end of the accident section to the accident point. Deep investigation method for fault points on power distribution lines.