SU1307401A1 - Method for automatic determination of distance to aerial electric power line fault location - Google Patents

Abstract

This invention relates to the field of electrical measurements. The purpose of the invention is to increase the reliability of determining the location of damage to the overhead power line. The device implementing the method comprises a system of 2 connections, a relay protection 3, an automatic reclosing unit 4, a switch 5, a receiver 6, a generator 7 and a processing and control unit 8 including input / output units 9, a central processing unit 10, operational units 11 memory device, read-only memory 12, timer block 13 and informational address bidirectional wake 14. Using the method ensures the achievement of the goal by significantly increasing the number of measurements (in times), which allows to improve the static processing of the signal-to-noise mixture, since the gain in the signal-to-noise ratio is proportional to the square root of the number of measurements. In addition, the use of the method reduces the time spent on finding the damage site by increasing the measurement accuracy, reducing the likelihood of misses. 2 hp f-ly, 2 ill. S / a

Description

The invention relates to electrical measuring equipment and is intended to automatically determine the distance to the place of damage, the cost of air from a power line.

The aim of the invention is to increase the reliability of determining the location of damage to an overhead transmission line by increasing the number of powders of the probe pulses, i.e. use of the entire possible probing time from start-up to extinguish the arc of make-up, and in case of unsuccessful automatic restarting (AR) and when the arc is burning when the high-voltage switch is restarted.

The method consists in receiving the reflected pulses separately before and after the beginning of the divergence of the contacts of the high-voltage switch, and depending on the disconnected phase, the average value of the voltage increases K, times; to compensate for changes in the input resistance of an overhead line during high-voltage switch switching (the coefficients K can be determined in advance for all variants of the switch state and entered into the memory block of the device implementing the device; information about the particular state of the switch can be obtained from the AR device) . In this method, all possible time of sounding the line from starting to extinguish the charging arc is used, and if the automatic reclosure is unsuccessful, and when the arc is burning during

restart, I

Fig, 1 shows a diagram of one and possible options for the implementation of sposb; 2 is a diagram illustrating its operation.

A device that implements the proposed method on a monitored power line 1 contains a system 2 connections, relay protection (RP) 3, block 4 AR and off 50 8, where the accumulation occurs, and the subsequent statistical processing of the remote control 10 according to the program written in ROM 12 It consists in finding the average value of the integ

Tel 5, receiver 6, generator 7, processing and control unit 8.

In this case, the processing and control unit 8 consists of input / output units (BVV) 9, the central processor voltage value in the device 10 (CAL) ,. operational from m periods of time. a memory block of its device (RAM) 11, a permanent storage device (ROM) 1.2, a block of 13 Thai units

In this case, signal processing in the pro

The interval of time from t to produced separately.

H H (BT), informational address address bidirectional bus 14.

Figure 2 indicated:

t IJ point in time of onset of damage F.JI;

(t, - tp) - the time of the relay protection. OHL;

(Чt) - time before the start

JO

switch on;

(tp) is the burning time of the short circuit train;

(t, - t) tg) - the operating time of the high-voltage switch;

(t,) H (tg) is the time of burning of the arc of the make-up) after switching off the high-voltage switch;

(ty- t) - AR pause;

tj - the moment of the command to turn on the high-voltage switch

0

five

thirty

(tg- t) is the turn on time of the high voltage breaker;

(tg) is the time of short-arc arc burning with the high-voltage switch turned on.

The device works as follows.

At the command of the RZ 3, the start-up device in the event of damage to the power line 1 at the time t depends on the operating time of the RZ 3. During the time t, the high-voltage switch 5 is turned off, but the arc at the site of damage continues to burn due to the feed current

35 phases to time point t.

In the time interval t, - t, the probe pulse generator 7 sends to the line, through the attachment system 2, probe pulses, which are reflected from overhead heterogeneities and, through the attachment system 2, enter the receiver 6 of the device. In receiver 6, filtering, amplification, detection and integration in time are m times less than the double run time of incoming signals, and converting them to a discrete form. From the receiver, the signals through the BBB 9 enter the RAM 11 of the block

50 8, where the WSS accumulates, and the subsequent statistical processing of the remote control 10 according to the program recorded in ROM 12. It consists in finding the average value of the integral values of the voltage in a Kald from m periods of time.

Voltage values in Caldom m periods of time.

At the same time, signal processing in proral values of voltage in the feces from m periods of time.

The interval of time from t to produced separately.

Pt4t goes offAfter the pause

The torus switching on of the high-voltage switch 5 during the time interval tg.Ecli IV turned out to be unsuccessful, i.e. in the place of damage, the arc lights up and burns up to time t, then the device, commanded by the LPV unit, starts at time t and can produce soundings up to time t,. The signals coming from the overhead line during this period are also accumulated in the RAM 1 1 of the block 8. The measurement time intervals are formed by the block 13 of the timers. Communication with the bus 14 of the block 8 is carried out through the blocks 9 of the input-output.

In order to eliminate the effect of a high level of interference when switching high-voltage switches

l - time intervals (t, - t) and (tj - t) filtering method can be used, based on a priori information about the properties of these interferences. It is known that their level significantly exceeds the level of the useful signal, and the frequency of such a process is such that with a single sounding lyi at the receiver input they act for more than half of the reception time. In each measurement, the number of pulses exceeding a given level, we can distinguish the specified time intervals. The device that implements the described algorithm is described in

Using the proposed method of automatically determining the distance to the damage point of an air-conditioned power line provides, compared to the existing ones, the accuracy of determining the distance to the damage point and range due to a significant increase in the number of measurements (by 10 times, which allows improve statistical processing of the signal-to-interference mixture, since the gain in the signal-to-interference ratio is proportional to the square root of the number of measurements

The application of the proposed method will reduce the time spent on finding the place of damage for

A way to increase the reliability of measurement, reduce the likelihood of a miss. The method can be used in determining the location of damage on an overhead line with a working voltage of 330 kV and above.

Claims (3)

Invention Formula one . The method of automatic determination of the distance to the place of damage to the power transmission line, consisting in THAT multiple probing pulses are sent to the line, receive reflected pulses arriving in each of the m periods. time, n times shorter than the time of the double run of the pulse along the whole line, determine the distance to the damage site, characterized in that, in order to increase the reliability, the reflected pulses are received in two periods of time before and after switching off the high-voltage switch , before the arc is completely extinguished, the average value of the voltage of the received pulses is measured for each of the m periods of time, in each of the measurement periods the average value of each of the m voltages measured after switching off the high voltage is multiplied switch K times, the resulting average voltage value is determined for each of the respective m time periods for both specified measurement intervals, compared with the corresponding voltage values measured in the intact line and the difference between the compared values of the specified threshold value voltage, fix the period of time from the total number t, corresponding to the distance to the place of damage. 2. Method of pop. 1, which differs from the fact that, in the case of unsuccessful restarting, additionally after switching on the line, similar operations are carried out in the automatic reclosing cycle, while increasing the average value of each hectare of voltages measured K times, and finding the resulting average value of the voltage is carried out in each of the m periods over all measurement intervals in the presence of damage including the initial emergency one. shutdown 3. Method POPP.1 and 2, characterized in that the coefficients K J and K, depending on which phases of the line are disconnected in the emergency mode 51307401 Press and auto-reclose mode are ,, 5j (,, .-з + 7 1 Е, rz; (Zr + z; r EG de 21- - matrix of the form fO 000 000 z, (z + z,) and z; (z; I -O- + (Zj) J - matrices of equivalent line input impedance in time intervals with f5 on Compiled by E. Kushch Editor M. Bandura Khred L. Oliynyk Order 1629/46 Circulation 731 Subscription VPIIPI USSR State Committee for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5 Printing and Publishing Enterprise, Uzhgorod, ul. Design, vy  and Z, E and the disconnected high-voltage switch, respectively; -matrix of the wave impedances of the wires (in phase coordinates); -matrices of the barriers resistance in the intervals of time when the switch is turned on and off;  generator output impedance matrix; -matrix emf generator. five .f ir i € t7 tg tg t Corrector S.Cherni