JPH10132889A - Fault point locating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To locate a fault point reliably by detecting the occurrence of the fault of a transmission line based on the detection value of a current, stopping the updating of a current waveform in a certain amount of time, and locating a fault point from the current waveform of a plurality of points. SOLUTION: When a grounding fault occurs at a transmission line between two iron towers, the polarity of a surge current is inverted between the detection values of the current sensor of both iron towers and the phases of the grounding current deviate by 180 deg. each other. A computer 10 judges that a fault occurred when the current value exceeds a predetermined threshold and the phases of the grounding current of adjacent local stations deviate by 180 deg. and enable local stations LS1-LS4 to stop updating the current waveform in a predetermined amount of time. After that, the computer 10 reads the current waveforms of the local stations LS1-LS4 from a ring buffer 11, compare and discuss them, and totally locate a fault point, thus achieving a reliable measurement with less influence, for example, by noise.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an accident point locating apparatus, and more particularly to an accident point locating apparatus for locating an accident point on a transmission line.

[0002]

2. Description of the Related Art In a conventional fault locating system, a current sensor and a local station (slave station) are provided in each of a plurality of sections of a transmission line, and a common main station (master station) is provided for all local stations. , Each local station detects whether an accident has occurred in the corresponding section based on the detection value of the corresponding current sensor,
The main station displayed the detection results of each local station.

[0003]

However, in the conventional accident point locating system, each local station independently locates the accident point, so that it is easily affected by noise and the like, and the reliability of the locating is low.

[0004] Therefore, a main object of the present invention is to provide a highly reliable fault locating device.

[0005]

The invention according to claim 1 is
A fault point locating device for locating a fault point on a transmission line, comprising: a plurality of current detecting means, a plurality of sampling means, a waveform forming means, a control means, and a locating means. The plurality of current detection units are provided corresponding to a plurality of predetermined points on the transmission line. Each current detecting means detects a current of the transmission line at a corresponding point. The plurality of sampling units are provided corresponding to the plurality of current detection units, respectively. Each sampling means samples the detection value of the corresponding current detection means at a predetermined cycle. The waveform forming means takes in the sampling values of the plurality of sampling means and forms current waveforms at a plurality of points. The control means detects occurrence of an accident in the transmission line based on the detection value of the current detection means, and stops updating the current waveform of the waveform forming means after a predetermined time. The locating means locates an accident point based on the current waveforms at a plurality of points of the waveform forming means whose updating of the current waveform has been stopped by the control means.

According to a second aspect of the present invention, an instruction means is further provided in the first aspect of the present invention. The command means is provided commonly to the plurality of sampling means, and provides a sampling command with a command number to the plurality of sampling means at a predetermined cycle. Each sampling means samples the detection value of the corresponding current detection means in response to a sampling instruction with each instruction number given from the instruction means, and supplies the sampled value and the instruction number to the waveform forming means.
The waveform forming means forms a current waveform based on the sampling value and the instruction number given from each sampling means.

According to a third aspect of the present invention, a clock signal generating means and a counter are further provided in the second aspect of the present invention. The clock signal generating means generates a clock signal. The counter is provided corresponding to each sampling unit and counts the number of pulses of the clock signal output from the clock signal generation unit. Each sampling means gives the sampling value and the count value at the time of sampling to the waveform forming means. The waveform forming means forms a current waveform based on the sampling value and the count value given from each sampling means.

According to a fourth aspect of the present invention, a clock signal generating means and a counter are further provided in the first aspect of the present invention. The clock signal generating means generates a clock signal. The counter is provided corresponding to each sampling unit and counts the number of pulses of the clock signal output from the clock signal generation unit. Each sampling means samples the detection value of the corresponding current detection means at a predetermined cycle according to the count value of the corresponding counter, and provides the sampling value and the count value at the time of sampling to the waveform forming means. The waveform forming means forms a current waveform based on the sampling value and the count value given from each sampling means.

According to a fifth aspect of the present invention, the clock signal generating means of the third or fourth aspect of the present invention stops outputting the clock signal for a predetermined period at a predetermined period,
The counter is reset in response to the stop of the output of the clock signal.

In the invention according to claim 6, a clock signal transmission line common to a plurality of counters according to the invention according to claim 3 or 4 is further provided. The clock signal generation means supplies a clock signal to a plurality of counters from one end of the clock signal transmission line. Each counter outputs a correction signal to the counter adjacent on the upstream side in the transmission direction of the clock signal in response to the count value reaching a predetermined value, and receives the correction signal from the counter adjacent on the downstream side. The count value is corrected based on the difference between the count value at that time and a predetermined value.

According to a seventh aspect of the present invention, the first and second counters common to a plurality of counters according to the third or fourth aspect of the invention are provided.
Are further provided. Two sets of clock signal generating means are provided. One of the two sets of clock signal generation means supplies a clock signal to the plurality of counters from one end of the first clock signal transmission line, and the other sets the second set of clock signal generation means.
From the other end of the clock signal transmission line to the plurality of counters. Each counter counts the sum of the number of pulses of the two clock signals supplied from the first and second clock signal transmission lines.

According to an eighth aspect of the present invention, the control means according to any one of the third to seventh aspects interrupts the input of a clock signal from the clock signal generation means to each counter, and outputs the current of the waveform forming means. Stop updating the waveform.

According to a ninth aspect of the present invention, the shape forming means according to any one of the first to eighth aspects is characterized in that the sampling means is provided with a sampling value given at a plurality of cycles of a predetermined cycle among the sampling values of each sampling means. And a peak value of a surge current caused by the occurrence of a fault in the transmission line.

According to a tenth aspect of the present invention, a plurality of sets of the waveform forming means according to any one of the first to ninth aspects are provided, and the control means differs from the previous time every time an occurrence of a transmission line accident is detected. The update of the current waveform of the waveform forming means is stopped.

According to an eleventh aspect of the present invention, the locating means according to any one of the first to tenth aspects comprises the step of: determining the location between a plurality of adjacent two points based on the amplitude and phase of the current waveform at the plurality of points. In which section of the section the accident point exists is located.

According to a twelfth aspect of the present invention, the locating means according to any one of the first to eleventh aspects comprises: a polarity of a surge current of a current waveform at a plurality of points; and a time at which the surge current reaches each point. Then, the distance from each point to the accident point is determined.

According to a thirteenth aspect of the present invention, there are provided a plurality of slave stations each provided at a plurality of predetermined points on a transmission line,
An accident point locating device for locating an accident point on a transmission line, including a master station provided in common for the plurality of slave stations,
It comprises a current detecting means, a sampling means, a waveform forming means, a detecting means, a control means, and a locating means. The current detecting means is provided in each slave station and detects a current of the transmission line at a corresponding point. The sampling means is provided in each slave station, and samples a detection value of the corresponding current detection means at a predetermined cycle. The waveform forming means is provided in the master station,
The sampling values of the sampling means of a plurality of slave stations are taken in to form current waveforms at a plurality of points. The detection means
The master station is provided and detects occurrence of a transmission line accident based on sampling values of sampling means of a plurality of slave stations.
The control means is provided in the master station, and stops updating the current waveform of the waveform forming means after a predetermined time in response to the detection means detecting the occurrence of the power line accident. The locating means is provided in the master station, and locates the fault point based on the current waveforms at a plurality of points of the waveform forming means whose updating of the current waveform is stopped by the control means.

According to a fourteenth aspect of the present invention, there are provided a plurality of slave stations each provided at a plurality of predetermined points on a transmission line,
An accident point locating device for locating an accident point on a transmission line, including a master station provided in common for the plurality of slave stations,
It comprises a current detecting means, a sampling means, a waveform forming means, a detecting means, a control means, and a locating means. The current detecting means is provided in each slave station and detects a current of the transmission line at a corresponding point. The sampling means is provided in each slave station, and samples a detection value of the corresponding current detection means at a predetermined cycle. The waveform forming means is provided in each slave station, and takes in a sampling value of the corresponding sampling means to form a current waveform at a corresponding point. The detecting means is provided in each slave station, and detects the occurrence of a transmission line accident based on the sampling value of the corresponding sampling means. The control means is provided in each of the slave stations or the master station, and stops updating of the current waveforms of the waveform forming means of all slave stations after a predetermined time in response to the detection means detecting occurrence of an accident in the transmission line. . The locating means is provided in the master station, and locates the fault point based on the current waveforms of the waveform forming means of all the slave stations whose updating of the current waveform is stopped by the control means.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION

[First Embodiment] FIG. 1 is a partially broken block diagram showing a configuration of a commercial power system to which an accident point locating system according to a first embodiment of the present invention is applied. It is a block diagram with a part omitted for explaining operation of a point location system.

Referring to FIGS. 1 and 2, the accident location system includes a plurality of towers 1.1 to 1.4,
A plurality of current sensors 3 provided on the transmission line 2 near
And a plurality of local stations LS1 to LS provided respectively corresponding to the plurality of steel towers 1.1 to 1.4,.
, Optical fibers (signal transmission lines) 4 forming loops extending back and forth between all the towers 1.1 to 1.4, and electric stations 5 such as substations. And a main station MS.

The current sensor 3 detects a current i of the transmission line 2. As shown in FIG. 2, the local station LS1 includes an optical data multiplex transmission device (MUX) 6 and an A / D
It includes a converter 7. The MUX 6 is a synchronization signal (sampling command) S with a count value (command number) n given from the main station MS via the optical fiber 4.
The YNC is converted into an electric signal and supplied to the A / D converter 7, and the digital data signal D ₁ (n) with the count value n supplied from the A / D converter 7 is converted into an optical signal and circulated through the optical fiber 50. To be mounted on the data frame 8.

The A / D converter 7 samples the analog detection value i1 of the current sensor 3 in response to the synchronization signal SYNC with the count value n.
Is converted into a digital data signal D ₁ (n) with a count value n and applied to the MUX 6. The same applies to the other local stations LS2 to LS4,.

The MUX 6 and the A / D converter 7
Of the operation signal, the data signal D ₁ (n
_{-1), D 2 (n-} 1), D 3 (n-2), D 4 (n-
2) may be mounted on one data frame 8.

The main station MS includes a MUX 9, a computer 10, and a ring memory 11. MUX
9 is a data signal D mounted on the data frame 8
_{1 (n-1) ~D 4} (n-2), together giving ... each computer 10 is converted into an electrical signal, the synchronization signal S with the count value n output from the computer 10
The YNC is converted into an optical signal and supplied to all the local stations LS1 to SL4 via the optical fiber 4.

The computer 10 has a built-in counter (not shown) and outputs a synchronization signal SYNC with a count value n to the MUX 9 at predetermined time intervals. As shown in FIG. 3, the computer 10 converts the data signals D ₁ (n−1) to D ₄ (n−2),... Given from the MUX 9 into count values n for each of the local stations LS1 to LS4,. They are rearranged in order, that is, in chronological order, and stored in the ring memory 11.

The ring memory 11 discards the oldest data signal each time a new data signal is input. Therefore, in the ring memory 11, current waveforms as shown in FIG. 4 are formed in the local stations LS1 to LS4,..., And each current waveform is updated every time a new data signal is input.

FIG. 4 shows a case where a ground fault occurs in the transmission line 2.
As shown in (1), a large surge current flows first, and then a stable ground fault current at the commercial frequency flows. For example, when a ground fault occurs between the towers 1.1 and 1.2 in FIG. 1, a ground fault current flows from the transmission line 2 to the fault point P. Therefore, the detection value i1 of the current sensor 3 of the tower 1.1 and the detection value i2 of the current sensor 3 of the tower 1.2 flow in opposite directions. That is,
In the detection values i1 and i2, the polarity of the surge current is reversed,
The phases of the ground fault currents are shifted from each other by 180 degrees.

The computer 10 determines that an accident has occurred when the current exceeds a predetermined threshold value Ith, and the phases of the ground fault currents of two adjacent local stations are shifted by 180 degrees, and the computer 10 determines a predetermined time. After that, the local stations LS1 to LS4 are instructed to stop sampling to stop updating the current waveform. This stop command is issued when a sampling stop command signal is output from the computer 10 to each of the local stations LS1 to LS4,..., Or when the output of the synchronization signal SYNC from the computer 10 is stopped.

After stopping the updating of the current waveform, the computer 10 reads the current waveforms of the local stations LS1 to LS8,... From the ring buffer 11 as shown in FIG. Is comprehensively determined.

Next, the operation of the accident point location system will be briefly described. From the computer 10 of the main station MS, all the local stations LS1-
LS4,... Are supplied with a synchronization signal SYNC with a count n at a constant cycle. Each local station LS1
The A / D converters 7 of the LS4,...
., Sampled by the current sensor 3 and converted into digital data signals D _{1 to} D ₄ ,. Data signals D _{1 to} D
_4, ..., the ring memory 11 to the local station Ls1 to Ls4, ... every time series by a computer 10
Is stored in When an accident occurs, the update of the waveform in the ring memory 11 is stopped by the computer 10 a predetermined time after the occurrence of the accident. The computer 10 reads each of the local stations LS <b> 1 to LS from the ring memory 11.
The current waveforms of S4,... Are taken out and compared, and the fault points are comprehensively located.

In this embodiment, the current waveforms of the local stations LS1 to LS4,... After the occurrence of an accident are taken out and comprehensively located. improves.

Further, the computer 10 sends a synchronization signal SYNC with a count value n to each local station LS1.
To LS4,... And each local station LS1 to
The A / D converters 7 of LS4,...
In response to the data signal D ₁ (n) with the count value n.
, D ₄ (n),... To the computer 10, and the computer 10 arranges the data signals D ₁ (n) to D ₄ (n),.
The current waveform of S4,... Is formed. Therefore, the current waveforms of the local stations LS1 to LS4,... Can be easily and accurately synchronized.

In this embodiment, the computer 10 stores all the data provided from each of the local stations LS1 to LS4,... In the ring memory 11, but provides a plurality of (for example, five) provided data. One of them
Only the data and the data of the surge current exceeding the threshold value Ith may be stored in the ring memory 11. In this case, the memory capacity of the ring memory 11 can be small.

In this embodiment, only one set of ring memories 11 is provided. However, as shown in FIG. 6, a plurality of sets of ring memories 11.1-11.4,... The update may be sequentially stopped by one set each time.
FIG. 6 shows a state in which the update of the current waveform of ring memory 11.1 is stopped and the update of the current waveform of other ring memories 11.2 to 11.4. In this case, even when a plurality of accidents occur consecutively, highly reliable orientation can be performed for each accident.

[Second Embodiment] FIG. 7 is a block diagram showing a configuration of an accident point locating system according to a second embodiment of the present invention.

Referring to FIG. 7, in this accident point location system, all local stations LS1 to LS5
… And the main station MS is one optical fiber 1
2 connected. The data frame F and the synchronization signal (not shown) are transmitted to the most upstream local station LS1.
Are transmitted to the downstream local stations LS2 to LS5,... Via the optical fiber 12. The local station LS1 outputs a data frame F at a constant cycle T as shown in FIG. Each local station L
S1～LS5, ... are mounted, as in the first embodiment, the detection value i1~i5 the corresponding current sensor 3, the digital data signal D ₁ to D ₅ samples the ..., is converted ... into each data frame F I do. Therefore, the main station M
S are supplied with data signals D _{1 to} D ₅ ,... Of all the local stations LS1 to LS5,.

The main station MS receives the data signal D
₁ to D _5, and stores ... in the ring memory 11 are arranged in time series to generate a plurality of current waveforms. Other configurations and operations are the same as those in the first embodiment, and a description thereof will not be repeated.

In this embodiment, the local station L1 located downstream from the local station LS1 located at the most upstream side
Since the data frame F is transmitted to S2 to LS5 and the main station MS, the data frame 8 is transmitted compared to the first embodiment in which the data frame 8 is transmitted so as to circulate through the local stations LS1 to LS5 and. The length of the optical fiber can be short.

[Third Embodiment] FIG. 9 is a block diagram showing a configuration of an accident point locating system according to a third embodiment of the present invention.

Referring to FIG. 9, in this accident point location system, all local stations LS1 to LS5
.. And the main station MS receive the clock signal CL.
Optical fiber 13 for transmitting K and data frame F
Are connected by an optical fiber 12 for transmitting the data. An oscillator 14 is provided in the main station MS, and a clock signal CLK is supplied from the oscillator 14 to all the local stations LS1 to LS5,. Also, as in the second embodiment,
The data frame F and a synchronization signal (not shown) are transmitted from the most upstream local station LS1 via the optical fiber 12 to the downstream local stations LS2 to LS5,.
And transmitted to the main station MS at a constant period T.

Each local station LSk (k = 1 to
5,...) Are the counter 15, A /
It includes a D converter 16 and a MUX 17. Counter 1
5 counts the number of pulses of the clock signal CLK and supplies the count value n to the A / D converter 16. A /
The D converter 16 detects the detection value ik of the corresponding current sensor 3
Is sampled at a constant period T, converted into a digital data signal D _k (n) with a count value n at the time of sampling, and given to the MUX 17. The MUX 17 has a data signal D
_k (n) is converted into an optical signal and mounted on a data frame F traveling in the optical fiber 12.

The main station MS receives the data signal D
_k (n) is stored in the ring memory 11 in the order of the count value n, that is, in chronological order, to generate a plurality of current waveforms. Other configurations and operations are the same as those in the first embodiment, and a description thereof will not be repeated.

In this embodiment, since the count value n at the time of sampling is added to each data signal _Dk , current waveforms at all points can be easily and accurately synchronized.

Although two optical fibers 12 and 13 are used in this embodiment, it goes without saying that only one optical fiber is required if a multiplexer / demultiplexer or a coupler is used.

[Embodiment 4] In Embodiment 3, each local station LS1 to LS5,.
Are provided, and the current waveforms at a plurality of points are synchronized by adding a count value n to the data signal D _k (n).

However, due to noise or the like, the count value n of the counter 15 is reduced by the local stations LS1 to LS5.
… May shift between them. This embodiment solves this problem.

FIG. 11 is a waveform chart for explaining an accident point locating system according to Embodiment 4 of the present invention.

Referring to FIG. 11, in this accident location system, clock signal C from main station MS is provided.
The output of the LK is stopped at a predetermined cycle for a predetermined time. Thereby, all the local stations LS1 to LS
Are reset to 0, and the count values of all the counters 15 are unified.

In this embodiment, since the count values n of the counters 15 of all the local stations LS1 to LS5,... Can be matched, current waveforms at all points can be accurately synchronized.

[Embodiment 5] In Embodiments 3 and 4,
A counter 15 is provided in each of the local stations LS1 to LS5,..., And the current waveforms at a plurality of points are synchronized by adding a count value n to the data signal D _k (n).
However, when the frequency of the clock signal CLK is extremely high and the optical fiber is long, the delay time of the transmission of the clock signal CLK cannot be ignored and the local stations LS1 to LS5 on the downstream side in the transmission direction of the clock signal CLK.
The smaller the counter, the smaller the count value n. This embodiment solves this problem.

FIG. 12 is a partially omitted block diagram showing a configuration of an accident point locating system according to Embodiment 5 of the present invention.

Referring to FIG. 12, in this fault locating system, each local station LSk, LSk + 1 is provided with a counter 21, a signal generator 22 and a counter corrector 23, and the downstream in the transmission direction of clock signal CLK. Signal generator 22 of the local station LSk on the side
And the counter correction unit 2 of the local station LSk + 1 adjacent to the upstream side of the local station LSk.
3 is connected by an optical fiber 13 '.

When the count value n of the counter 21 reaches a predetermined value n1, the signal generation unit 22 of the downstream local station LSk sends the optical fiber 13 to the counter correction unit 23 of the upstream local station LSk + 1. ′.

The counter correction unit 23 of the local station LSk + 1 is connected to the downstream local station LSk.
In response to the correction signal φa, the count value of the counter 21 corresponding to 値 of the value obtained by subtracting the count value n1 from the count value n2 of the corresponding counter 21 (n2−n1) / 2 Reduce. This makes it possible to correct the difference in the count value due to the delay of the clock signal, and to accurately synchronize the current waveforms at all points.

[Sixth Embodiment] FIG. 13 is a partially omitted block diagram showing a configuration of an accident point locating system according to a sixth embodiment of the present invention.

Referring to FIG. 13, in this fault locating system, optical fibers 13, 13 'for transmitting a clock signal are provided.
Are provided, and two clock signals CLK and CLK 'are provided.
Are transmitted in opposite directions through the optical fibers 13 and 13 ', respectively.

Each local station LSk, L
Sk + 1 has two sets of counters 24, 24 'and an adder 25. One of the counters 24 is an optical fiber 13
The counter 24 'counts the number of pulses of the clock signal CLK' transmitted through the optical fiber 13 '. The adder 25 adds the count value of one counter 24 and the count value of the other counter 24 '. The output n of this adder 25 is used as the data signal D as a count value.
k, Dk + 1.

In this embodiment, the clock signal CLK
And CLK 'are transmitted in opposite directions, so that the sum of the delay time of clock signal CLK and the delay time of clock signal CLK' is determined by each local station LSk, LSk + 1.
At each local station LSk,
The output value n of the adder 25 of LSk + 1 becomes equal. Therefore, current waveforms at all points can be accurately synchronized.

[Seventh Embodiment] FIG. 14 is a block diagram showing a configuration of an accident point locating system according to a seventh embodiment of the present invention.

Referring to FIG. 14, in this accident location system, all local stations LS1 to LS
, And the main station MS receives the clock signal C
The optical fiber 13 for transmitting the LK and the optical fiber 12 for transmitting the data frame F are connected.
An oscillator 14 is provided in the main station MS, and a clock signal CLK is supplied from the oscillator 14 to all the local stations LS1 to LS5,. Also, as in the second embodiment,
The data frame F and a synchronization signal (not shown) are transmitted from the most upstream local station LS1 via the optical fiber 12 to the downstream local stations LS2 to LS5,.
And transmitted to the main station MS at a constant period T.

Each local station LSk is configured as shown in FIG.
As shown in the figure, the counter 31, the surge detector 32, the A /
It includes a D converter 33 and a MUX. Counter 3
1 counts the number of pulses of the clock signal CLK and gives the count value n to the surge detector 32. When the absolute value of the detection value ik of the corresponding current sensor 3 exceeds a predetermined threshold value Ith, the surge detection unit 32 determines the polarity (+ or-) of the surge current and the count value n at that time. It is provided to the MUX 34 as a digital data signal.

The A / D converter 33 samples the detected value ik of the current sensor 3 at a constant period T, converts the sampled value into a digital data signal, and
Give to.

The MUX 34 includes the surge detector 32 and the A
The data signal _Dk provided from the / D converter 33 is converted into an optical signal and mounted on a data frame F traveling in the optical fiber 12. As shown in FIG. 16, the data signal _Dk includes the sampled current value, the polarity and the count value of the surge current. The main station MS
As shown in FIG. 17, the data signals _Dk are arranged in the order of frame numbers, that is, in chronological order, for each local station LSk, stored in the ring memory 11, and form a current waveform at each point.

In FIG. 17, the data on the surge current is transmitted three times at a time because the data transmission may fail if transmitted only once. In other words, if the data is transmitted three times, no failure occurs three times, so the data can be transmitted reliably.

The main station MS detects the occurrence of an accident based on the current waveform of each local station LSk, and stops updating the current waveform after a predetermined time. Next, the main station MS locates the accident section based on the current waveform of each local station LSk whose updating has been stopped. Further, the main station MS calculates the distance from the fault section and the local stations LSk, LSk + 1 on both sides thereof to the fault point based on the data on the surge current.

Here, the main station MS is connected to the accident section and the local stations LSk, LS on both sides thereof.
A method for calculating the distance from k + 1 to the accident point will be described. Referring to FIG. 18, local station LS
The count values at the same time of 1 to LS4 are n1 to n4, respectively.
The delays of the count values due to the delay of the clock signal CLK between the local stations LS1 and LS2, LS2 and LS3, and LS3 and LS4 are Δn12 and Δn2, respectively.
3, Δn34, n1 = n2−Δn12, n2 =
n3-Δn23, n3 = n4-Δn34.

When a ground fault occurs at a time t _F between the local stations LS 2 and LS 3 and at a position x (m) from the local station LS 2, a time t 2 at which the surge current reaches the local station LS 2.
Is _{t2 = t F + x / v} S , and the time t3 when the surge current reaches a local station LS3 is t3 = t _F +
A _{(L23-x) / v S} . However, when the surge propagation speed is v _S (m / μsec), the local station LS2
The distance between and LS3 is L23 (m).

The time difference t2-t3 when the surge current reaches the local stations LS2 and LS3 is t2-t3 =
The _{(2x-L23) / v S} . This time difference t2-t3
The difference ΔCN between the count values of the local stations LS2 and LS3 corresponding to the following equation is ΔCN = (t2−t3) / T ₀
= A _{(2x-L23) / T 0} · v S. Note that the cycle of the clock signal CLK is T ₀ (μsec).

Therefore, the difference ΔCN ′ between the count values of the local stations LS2 and LS3 in consideration of the delay of the clock signal CLK is ΔCN ′ = ΔCN−n23.

Now, as shown in FIG. 19, the local stations LS1 and LS2, LS2 and LS3, LS3 and LS
4 are 3 km, 5 km, and 4 km, respectively, the polarities of the surge currents detected in the local stations LS1 to LS4 are +, +,-, and-, respectively, and the surge currents are detected in the local stations LS1 to LS4. When the count value is 184
6, 1096, 1215, and 2215.

The fault section is a section between local stations LS2 and LS3 where the polarity of the surge current is reversed. For the sake of simplicity, if the delay of the clock signal CLK is ignored, x = ΔCN = (2 × −L23) / T ₀ · v _S
(ΔCN · T ₀ · v _S + L23) / 2. Also, v
Assuming that _s = 200 m / μsec and T ₀ = 20 ns, x
= (− 119 · 0.02 · 200 + 5000) / 2 = 2
262 m.

If there is no contradiction between the result of locating the fault section based on the current waveform and the result of calculating the fault point based on the surge current, the main station MS displays both the fault section and the fault point. In such a case, priority is given to the orientation result based on the current waveform, and only the accident section is displayed.

In this embodiment, the fault section and the fault point are located from the current waveform and the surge current, so that the reliability and accuracy of the location are improved.

[Eighth Embodiment] FIG. 20 is a partially omitted block diagram showing the configuration of an accident point locating system according to an eighth embodiment of the present invention. FIG. 21 shows the configuration of local station LSk shown in FIG. FIG.

Referring to FIGS. 20 and 21, in this accident point location system, all local stations L
S1 to LS3, and the main station MS are connected by an optical fiber 13 for transmitting a clock signal CLK and an optical fiber 12 for transmitting data.
The main station MS is provided with an oscillator 14, and a clock signal CLK is supplied from the oscillator 14 to all the local stations LS1 to LS3,.

Each local station LSk is configured as shown in FIG.
, Buffers 41 and 42, counter 43A /
D converter 44, ring memory 45, computer 4
6 and MUS47. Buffers 41 and 42 amplify clock signal CLK. The counter 43 counts the number of pulses of the clock signal CLK, and specifies an address of the ring memory 45 based on the count value. A / D
The converter 44 samples the detected value ik of the corresponding current sensor 3 in synchronization with the clock signal CLK, converts the sampled value into a digital data signal, and supplies the digital data signal to the ring memory 45.

The ring memory 45 stores the data signal given from the A / D converter 44 at the address designated by the counter 43. A current waveform as shown in FIG. 22 is formed in the ring memory 45, and the current waveform is updated in synchronization with the clock signal CLK.

The computer 46 detects the occurrence of an accident based on the current waveform formed in the ring memory 45,
That fact is transmitted to the main station MS via the MUX 47. The main station MS stops transmitting the clock signal CLK to the local stations LS1 to LS3,... In response to the signal from the computer 46 of the local stations LS1, LS3,. The update of the current waveform in 45 is stopped.

The computer 46 of the local station LSk transmits the stopped current waveform to the main station MS. As shown in FIG. 23, current waveforms of the local stations LS1 to LS3,... Are stored in the memory device 48 of the main station MS. The main station MS determines the fault section based on the fault current of the commercial frequency in the current waveforms of the local stations LS1 to LS3 stored in the main memory device 48, and determines the local station LS1 to LS3.
The fault point is located on the basis of the polarity and address of the surge current in the current waveform of.

In this embodiment, the ring memory 45 is provided in each of the local stations LS1 to LS3,..., And a current waveform is formed in each of the local stations LS1 to LS3,.
The current waveform of S1 to LS3,.
Is transmitted to Therefore, each local station L
Embodiment 1 in which it is necessary to transfer the current detection values of S1 to LS3 to the main station MS in real time.
7, each of the local stations LS1 to LS3,
.. To the main station MS.

In this embodiment, the computer 46 of the local station which has detected the occurrence of the accident notifies the main station MS of the occurrence of the accident, and the main station MS transmits the information to the local stations LS1 to LS3.
..., but the local stations that have detected the occurrence of the accident are all local stations LS
The update of the current waveforms of 1 to LS3,... May be stopped directly.

[0082]

As described above, according to the first aspect of the present invention, updating of current waveforms at all points is stopped in response to occurrence of an accident, and an accident point is determined based on current waveforms at all points. Since the orientation is comprehensive, it is less susceptible to noise and the like than before, and the reliability of the orientation is improved.

According to the second aspect of the present invention, each sampling means of the first aspect of the invention samples a current value in response to a sampling instruction with each instruction number given from the instruction means, and the sampling value and the instruction The number is given to the waveform forming means. Therefore, the current waveforms at all points can be easily and accurately synchronized.

According to a third aspect of the present invention, in addition to the second aspect of the present invention, a counter driven by each clock signal is provided, and a count value at each sampling is given to the waveform forming means. Therefore, the current waveforms at all points can be easily and accurately synchronized.

According to a fourth aspect of the present invention, each of the sampling means of the first aspect of the present invention detects a current value in accordance with a count value of a counter driven by a clock signal, and converts the sampled value and the count value into a waveform forming means. Give to.
Therefore, the current waveforms at all points can be easily and accurately synchronized.

In the invention according to claim 5, the clock signal generating means according to claim 3 or 4 stops outputting the clock signal for a predetermined period for a predetermined time, and each counter stops the clock signal. Reset accordingly. Therefore, the count values of the counters at all points can be easily unified.

In the invention according to claim 6, each counter according to claim 3 or 4 outputs a correction signal to the upstream counter in response to the count value reaching a predetermined value, and outputs the correction signal to the downstream counter. The count value is corrected based on the difference between the count value when the correction signal is received from the counter and the predetermined value. Therefore, it is possible to easily correct the difference in the count value between the counters at each point due to the delay in transmission of the clock signal.

According to the seventh aspect of the present invention, the clock signal is supplied from both the upstream side and the downstream side.
Each counter of the invention according to the invention counts the sum of the pulse numbers of both the clock signal supplied from the upstream side and the clock signal supplied from the downstream side. Therefore, it is possible to easily correct the difference in the count value between the counters at each point due to the delay in transmission of the clock signal.

In the invention according to claim 8, the control means according to any one of claims 3 to 7 cuts off the input of the clock signal to each counter to stop updating the current waveform of the waveform forming means. Therefore, updating of the current waveform can be easily stopped.

In the ninth aspect of the present invention, the waveform forming means according to any one of the first to eighth aspects selectively acquires a sampling value and a surge current peak value provided at a plurality of cycles of the sampling cycle. Put in. Therefore, the capacity of the waveform forming means can be reduced.

According to the tenth aspect of the present invention, a plurality of sets of the waveform forming means according to any one of the first to ninth aspects are provided, and the control means sets the current waveform of the waveform forming means different from the previous time every time the occurrence of an accident is detected. Stop updating. Therefore,
Even if multiple accidents occur consecutively, the accident point of each accident can be located.

In the invention according to claim 11, the locating means according to any one of claims 1 to 10 locates an accident section based on the amplitude and phase of the current waveform at all points. Therefore, the accident section can be easily and quickly located.

In the twelfth aspect, the locating means according to any one of the first to eleventh locates the distance from each point to the fault point based on the polarity and time of the surge current that has reached each point. Therefore, the accident point can be accurately located.

In the invention according to claim 13, a slave station is provided at each point, a common master station is provided for a plurality of slave stations, and means other than the current detecting means and the sampling means are provided in the master station. Therefore, the configuration of each slave station can be simplified.

In the fourteenth aspect, in addition to the current detecting means and the sampling means, a waveform forming means and a detecting means are provided in each slave station. Therefore, since each slave station only needs to transmit the current waveform to the master station after the occurrence of the accident, it is necessary to transmit the current value to the master station in real time.
As compared with the invention according to the third aspect, data transmission from each slave station to the master station can be easily performed.

[Brief description of the drawings]

FIG. 1 is a partially broken block diagram showing a configuration of a power system in which an accident point location system according to Embodiment 1 of the present invention is employed.

FIG. 2 is a partially omitted block diagram for explaining the operation of the accident point locating system shown in FIG. 1;

FIG. 3 is a partially broken view for explaining the operation of the computer shown in FIG. 2;

FIG. 4 is a diagram for explaining a current waveform formed in the ring memory shown in FIG. 2;

FIG. 5 is another diagram for explaining the operation of the computer shown in FIG.

FIG. 6 is a partially omitted view showing an improved example of the accident point locating system shown in FIG. 1;

FIG. 7 is a block diagram showing an accident point location system according to Embodiment 2 of the present invention.

8 is a waveform chart for explaining the operation of the accident point locating system shown in FIG. 7;

FIG. 9 is a block diagram showing a configuration of an accident point location system according to Embodiment 3 of the present invention.

FIG. 10 is a diagram showing a configuration of a local station shown in FIG.

FIG. 11 is a waveform chart for explaining an accident point locating system according to Embodiment 4 of the present invention.

FIG. 12 is a partially omitted block diagram showing a configuration of an accident point location system according to Embodiment 5 of the present invention.

FIG. 13 is a partially omitted block diagram showing a configuration of an accident point location system according to Embodiment 6 of the present invention.

FIG. 14 is a block diagram showing a configuration of an accident point location system according to Embodiment 7 of the present invention.

15 is a block diagram illustrating a configuration of a local station illustrated in FIG.

FIG. 16 is a diagram for describing the data signal shown in FIG.

FIG. 17 is a diagram for explaining a current waveform formed in the main station shown in FIG.

FIG. 18 is a diagram for explaining a method of locating an accident point from the data signal described in FIG.

FIG. 19 is another diagram for explaining a method of locating an accident point from the data signal described in FIG. 16;

FIG. 20 is a block diagram showing a configuration of an accident point location system according to Embodiment 8 of the present invention.

FIG. 21 is a block diagram showing a configuration of a local station shown in FIG.

FIG. 22 is a diagram showing a current waveform formed in the local station shown in FIG.

FIG. 23 is a diagram showing a current waveform formed in the main station shown in FIG.

[Explanation of symbols]

1.1-1.4 Steel tower 2 Transmission line 3 Current sensor 4,12,13,13 'Optical fiber 5 Electric station 6,9,17,34,47 Optical data multiplex transmission equipment (MUX) 7,16,33 , 44 A / D converter 8, F data frame 10, 46 Computer 11, 11.1-11.4, 45 Ring memory 14 Oscillator 15, 21, 24, 24 ', 31, 43 Counter 22 Signal generator 23 Counter correction Part 25 adder 41,42 buffer 48 memory device LS local station MS main station

Claims (14)

[Claims] An accident point locating device for locating an accident point on a transmission line, wherein each of the accident point locating devices is provided corresponding to a plurality of predetermined points on the transmission line, and the transmission line is located at a corresponding point. A plurality of current detecting means for detecting a current, each of which is provided corresponding to the plurality of current detecting means, and a plurality of sampling means for sampling a detection value of the corresponding current detecting means at a predetermined cycle; Waveform forming means for taking the sampling values of the plurality of sampling means and forming current waveforms at the plurality of points; detecting occurrence of an accident of the transmission line based on a detection value of the current detecting means, and presetting Control means for stopping updating of the current waveform of the waveform forming means after a lapse of time, and the duplication of the waveform forming means for which updating of the current waveform is stopped by the control means. Comprises locating means for locating the fault point based on the point of the current waveform, the fault point locating system. 2. The apparatus according to claim 1, further comprising: command means provided in common with said plurality of sampling means, for giving a sampling command with an instruction number to said plurality of sampling means at said predetermined period. In response to the sampling instruction with each instruction number given from the sampler, samples the detection value of the corresponding current detection means, and provides the sampled value and the instruction number to the waveform forming means, 2. The fault point locating apparatus according to claim 1, wherein the current waveform is formed based on a sampling value and a command number given from a sampling unit. 3. A clock signal generating means for generating a clock signal, and a counter provided corresponding to each sampling means for counting the number of pulses of the clock signal output from the clock signal generating means. Each sampling means gives the sampling value and the count value at the time of sampling to the waveform forming means, and the waveform forming means converts the current waveform based on the sampling value and the count value given from each sampling means. The accident point location device according to claim 2, wherein the device is formed. 4. A clock signal generating means for generating a clock signal, and a counter provided corresponding to each sampling means for counting the number of pulses of the clock signal output from the clock signal generating means. Each sampling means samples the detection value of the corresponding current detection means at the predetermined cycle according to the count value of the corresponding counter, and provides the sampled value and the count value at the time of sampling to the waveform forming means; The fault point locating device according to claim 1, wherein the forming means forms the current waveform based on the sampling value and the count value given from each sampling means. 5. The clock signal generating means stops outputting the clock signal for a predetermined period of time at a predetermined period, and resets the counter in response to the stop of the output of the clock signal. Item 5. The accident point location device according to item 3 or 4. 6. A clock signal transmission line commonly provided to a plurality of said counters, wherein said clock signal generation means supplies said clock signal to said plurality of counters from one end of said clock signal transmission line. Each of the counters outputs a correction signal to a counter adjacent on the upstream side in the transmission direction of the clock signal in response to the count value reaching a predetermined value, and outputs a correction signal from the counter adjacent on the downstream side. The accident point locating device according to claim 3 or 4, wherein the count value is corrected based on a difference between the count value at the time of reception and the predetermined value. 7. The apparatus according to claim 1, further comprising: first and second clock signal transmission lines provided in common for the plurality of counters, wherein two sets of the clock signal generating means are provided, and One of the counters supplies the clock signal to the plurality of counters from one end of the first clock signal transmission line, and the other supplies the clock signal to the plurality of counters from the other end of the second clock signal transmission line. 5. The fault point locating device according to claim 3, wherein each counter counts the sum of the number of pulses of two clock signals supplied from the first and second clock signal transmission lines. 6. 8. The control unit according to claim 3, wherein the control unit interrupts the input of the clock signal from the clock signal generation unit to each counter to stop updating the current waveform of the waveform forming unit. The accident point locator described in Crab. 9. The waveform forming means according to claim 1, wherein said sampling value of each sampling means is a sampling value provided at a cycle that is a multiple of said predetermined cycle, and a peak of a surge current caused by occurrence of an accident of said transmission line. The accident point locating device according to claim 1, wherein the value is selectively taken. 10. The apparatus according to claim 1, wherein a plurality of sets of the waveform forming means are provided, and the control means stops updating of the current waveform of the waveform forming means different from the previous time every time the occurrence of an accident of the transmission line is detected. 10. The accident point location device according to any one of claims 9 to 9. 11. The locating means according to claim 1, wherein a plurality of adjacent two or more points are determined based on an amplitude and a phase of the current waveform at the plurality of points.
The fault point locating device according to any one of claims 1 to 10, wherein the fault point locating device determines which section of the section between the two points has the fault point. 12. The locating means determines a distance from each point to the accident point based on a polarity of a surge current of a current waveform at the plurality of points and a time when the surge current reaches each point. The accident point location device according to any one of claims 1 to 11, which performs location. 13. A transmission line including a plurality of slave stations each provided at a plurality of predetermined points on a transmission line and a master station commonly provided to the plurality of slave stations, and locating an accident point of the transmission line. Current detecting means provided at each slave station for detecting the current of the transmission line at a corresponding point, and detecting the corresponding current detecting means provided at each slave station. Sampling means for sampling a value at a predetermined cycle, a waveform forming means provided in the master station, taking in a sampling value of the sampling means of the plurality of slave stations, and forming a current waveform at the plurality of points; Detecting means provided in the master station and detecting occurrence of an accident of the transmission line based on a sampling value of the sampling means of the plurality of slave stations; provided in the master station, wherein the detecting means is the transmission line. Control means for stopping the update of the current waveform of the waveform forming means after a predetermined time in response to the detection of the occurrence of, and a waveform provided in the master station, the update of the current waveform being stopped by the control means An accident point locating device, comprising: locating means for locating the fault point based on current waveforms at the plurality of points of the forming means. 14. A transmission line including a plurality of slave stations provided at a plurality of predetermined points on a transmission line, and a master station commonly provided to the plurality of slave stations, for locating an accident point of the transmission line. Current detecting means provided at each slave station for detecting the current of the transmission line at a corresponding point, and detecting the corresponding current detecting means provided at each slave station. Sampling means for sampling a value at a predetermined cycle, provided in each slave station, waveform forming means for taking in the sampling value of the corresponding sampling means and forming a current waveform at a corresponding point, provided in each slave station Detecting means for detecting the occurrence of an accident in the transmission line based on the sampling value of the corresponding sampling means, provided in each slave station or the master station, wherein the detecting means detects the occurrence of the accident in the transmission line. Accordingly, control means for stopping updating of the current waveform of the waveform forming means of all slave stations after a predetermined time, and all slave stations provided in the master station and for which updating of the current waveform is stopped by the control means An accident point locating device, comprising: locating means for locating the accident point based on the current waveform of the waveform forming means.