JPS62150177A - Transmission line fault section location system - Google Patents

Abstract

PURPOSE:To simplify the construction, by connecting two light emitting diodes reverse to each other to a current transformer for detecting troubled current to be shared at the interface between adjacent trouble detected sections to obtain two optical signals for reducing the number of transformers at interface points to six only. CONSTITUTION:Light emitting diodes 12b-12f are connected in the same direction to respective current transformers 8b-8f in a fault detected section a of (A) system while the connection of the light emitting diodes 12'' and 12f' is made opposite in the direction in adjacent detection sections A' and A''. Two light emitting diodes 12xa and 12yg' are connected to a current transformer 8a at a demarcation point between the sections A and A' opposite in the direction while light emitting diodes 12xa'' and 12yg connected to a current transformer 8g in parallel in the opposite direction at the demarcation point between the sections A and A''. Respective optical signals of the diodes 12xa and 12yg' are applied to a discriminator 10b at a transmission terminal section 100b for the sections A and A' and to a discriminator of a transmission terminal in the section A' not illustrated. Likewise, optical signals of the diodes 12yg and 12xa'' are inputted into the discriminator 10b and to a discriminator at the section A'' not illustrated.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a power transmission/distribution line fault section locating system.

[Prior art] Conventionally, as a fault area locating system for power transmission and distribution lines, a current transformer (hereinafter referred to as CT) is installed on the overhead ground wire of each tower of the power transmission and distribution line to detect the fault current of the overhead ground wire in the event of a flash fault, etc. A system is known in which a so-called follow current is detected, and a phase difference between signals proportional to the amplitude of the follow current, which are outputs of two adjacent current transformers, is detected to locate an accident area.

FIG. 5 is a block diagram showing the configuration of one transmission terminal station of a conventional transmission line fault section locating system.

Referring to FIG. 5, the configuration of one transmission terminal station will be described centering around transmission terminal station 100b. In Figure 5,
The power transmission system 210 is divided into detection sections A, A', A-, etc. having appropriate distances, and within each detection section, a plurality of detection points 140a to +40g are located at an appropriate distance from the overhead area of the power transmission system 210. CTs 8a to 8g are provided in non-contact and close proximity to the wire 6, respectively.

Each detection point is provided near a steel tower of the power transmission system 210, for example. Further, at the detection point 140d, a transmission terminal station 100b including a discrimination device 10b and an optical transmission device 20b is provided. A" to the detection zone, detection points 140g' and 140 as detection points 140g and 1408 on the boundary between A and A"
", for example, are installed on the same tower, and each CT8
CT8f' is provided at the detection point !401'', and a detection point 140b'' is provided.

At both output ends of each C'F, the emission wavelengths are λ,
λ2. Well, different light emitting diodes I 2f
", 12g', I 2a to 12g, I 2a",
I2b" is connected, and each CT and each light emitting diode constitute a completed CT. That is, in each completed CT, for example, the light emitting diode 12d is caused to emit light by the secondary current of the overhead ground wire 6 detected by the CT8d. , the optical signal output is transmitted to the discrimination device 10 via the optical fiber cable 9d.
Transmit to b. The above light emitting diodes 12a to 12g
Optical signal output of each fiber optic cable 91", 9g'
The signal is transmitted to the discriminating device 10b of the transmission terminal station 100b via the transmission terminal station 100b.

In addition, the light emitting diodes 12f' and 12g in the detection section A°
' optical signal output from each optical fiber cable 9f', 9g
' is transmitted to the discrimination device (indicated by U' in the figure) of the transmission terminal station 100a for the detection interval A°. Similarly, one line is formed for the detection section A''.

The six current transformers 88 to 8g, 81", 8g', etc. are wound in the same direction, and each light emitting diode is connected so that the polarity is the same in any detection section as shown in the figure.

The discrimination device 10b of the transmission terminal station 100b measures the phase difference of the optical signals from adjacent detection points among the manually input optical signals from each detection point, and determines that an optical signal with a phase difference of +80° was transmitted. The area between adjacent detection points is determined to be an accident area. Information regarding this accident section is output to the optical transmission device 2ob, and then transmitted to the optical transmission device 20b via the optical fiber cable 110c from the transmission terminal station IQOcL; The information outputted from the optical transmission device 20b is added to the information and modulated with an optical signal of wavelength λ1.The optical signal is transmitted to the optical fiber cable 110b and the transmission terminal station 100a in the detection section A°.
Therefore, the information regarding the accident section obtained from each transmission terminal station is collected at the mask station, and the operator uses the monitoring device of the mask station to determine the accident section. can be grasped instantly.

[Problems to be Solved by the Invention] In the conventional system shown in FIG. 5, each detection section A, !
=A', separate current transformers 8a at the demarcation points of A and A''
, 8g' or 8g and 8g' light emitting diode I 2
a, 12g', l 2g, 12f' are provided,
The current in the overhead ground wire 6 is detected. Therefore, in the conventional system, two current transformers and a light emitting diode connected to each current transformer must be provided at the demarcation point, which is uneconomical.

The detection currents of the overhead ground wires 6 detected at adjacent detection points at the above-mentioned demarcation point are almost in phase, and due to the principle of locating the accident zone mentioned above, only one current transformer is installed at the above-mentioned adjacent detection points. It is possible to configure That is, for example 1
Two current transformers 8 are connected at the output end of the current transformer 8 in parallel with the same polarity as shown in FIG. 6, or in cascade with the same polarity as shown in FIG. One possible method is to connect two light emitting diodes 12m and 12n to obtain an optical signal, but there is a problem that when the current flowing through the overhead ground wire 6 is small, the light emitting diodes 12m and 12n do not emit light.

[Objective of the Invention] The object of the present invention is to solve the above problems, and to provide a single current transformer for detecting the current of the overhead ground wire at the boundary of the detection section,
And to provide a transmission/distribution line fault section locating system which can still obtain two sufficient optical signals by connecting two light emitting diodes.

[Structure of the Invention] The present invention provides light emitting diodes in the same polarity direction on the output side of a plurality of fault current detection current transformers wound around the overhead ground wire of a power transmission/distribution line within the same fault detection section. At the same time, in the adjacent fault detection sections, a light emitting diode is connected to the output side of each current transformer in a direction opposite to the above polarity, and at the boundary between the two adjacent fault detection sections, a light emitting diode is connected to the output side of each of the current transformers, and a light emitting diode is connected to the output side of each of the current transformers in the opposite direction to the above polarity. A current transformer for fault current detection is provided, and two light emitting diodes facing in opposite directions are connected to the shared current transformer.

[Operation] With the above configuration, by measuring the phase difference between the outputs of a plurality of light emitting diodes within the same fault detection section, the phase difference between the outputs of adjacent light emitting diodes on the overhead ground wire becomes 180°. It is possible to identify a section where the following occurs as an accident section.

[Example] Are the constituent parts in Fig. 1 the same as those in Fig. 6? These are given the same reference numerals.

In FIG. 1, each CT8b to 8r in the detection area A
The light emitting diodes 12b to 12r are connected in the same direction. On the other hand, in the adjacent detection sections A' and A'', the connection direction of the light emitting diodes 12b'' and 12f'' is the detection section A.
The connection direction of the light emitting diodes is opposite to that in . In addition, two light emitting diodes 12xa are connected to the current transformer 8a at the demarcation point of the detection section! 2yg' are connected in opposite directions and in parallel.

The optical signal from the light emitting diode 12xa is manually inputted to the discriminator 10b of the transmission terminal station 100b via the optical fiber cable 9a. On the other hand, the optical signal of the light emitting diode 12 yg' is inputted to the discrimination device (not shown) of the transmission terminal station 100a for the detection section A' via the cable 9g'.

Similarly, current transformer 8g is located at the demarcation point between detection zones A and A''.
The light emitting diodes 12xa'' and 12yg are connected in parallel in opposite directions, and the optical signal of I2Yg is manually inputted to the discrimination device 10b via the optical fiber cable 9g.
The optical signal of 2xa" is sent to the transmission terminal station 100 for the detection section A".
The information is input to a discriminator (not shown) at c.

With the above configuration, for example, detection point 1 of detection section A
When an accident occurs at the accident point P1 in the section between 40c and 140d, and a follow-on stream flows, the follow-on stream flows in both directions on the overhead ground wire 6 with the accident point P as the center.

Therefore, the discriminator t of the transmission terminal station toob in the detection section A
Light emitting diodes 12d and 12e are input to ab.

12 f,”I 2 yg optical signal and light emitting diode 1
2c, 12b.

CT8c connected to light-emitting diodes 12c and 12d such that the phase difference of the optical signal of +2xa is 180°, and the phase of the optical signal of the light-emitting diode 12c is opposite to the phase of the optical signal of the adjacent light-emitting diode 12d. and 8
The discriminating device 10b determines that the interval d, that is, between the detection points 140c and 140d is an accident zone. Note that the light emitting diodes 12f and t2y in the detection section A'
The optical signals output from the light emitting diodes 12xa'' and 12b'' in the detection interval Δ'' are in phase, and the optical signals output from the light emitting diodes 12xa'' and 12b'' in the detection interval Δ'' are in phase.
J and each detection section A', A where no accident has occurred in
It is determined by the transmission terminal station 100a, IoOc determination device.

Next, for example, the detection points 1401'' and 1 in the detection area A°
When an accident occurs at the accident point P in the section of 40g' and a follow-on stream flows, the follow-on stream flows in both directions on the overhead ground wire 6 centering on the accident point P2, as described above.

Therefore, the optical signals of the light emitting diodes 12xa, +2b to +21.!2yg that are manually input to the transmission terminal station [(Job discriminator 10b) in the detection section A are all in phase, and
The determination device Job of the transmission terminal station 100b in the detection zone A determines that "no accident has occurred within the detection zone A." Further, the optical signals outputted from the light emitting diodes 12f and 12yg° have opposite phases, and each optical signal is input to a discriminator (not shown) of the transmission terminal station [00a] in the detection section A'. As a result, the discriminating device of the transmission terminal station 100a in the detection section determines that the section of the detection points +4Or' and 140g', which are provided with the light emitting diodes +2r and +2Yg', respectively, is the accident section.

As shown in the block diagram of Fig.
), when the terminal A side of CT 8a is 10, only the light emitting diode 12xa emits light, while the terminal
When the 3 side is 10, only the light emitting diode +2yg' emits light. Therefore, current flows through the light emitting diodes one by one for each positive and negative cycle of the alternating current output by the current transformer 8a, and the light emitting diodes emit light, so that the load placed on the CT 8a is reduced compared to the configuration of FIG. 6 or 7. Therefore, it becomes possible to detect the following flow even when the following flow is small.

As shown in FIG. 1, the signal is transmitted from the light emitting diode at the detection point to the discrimination device 10b as follows.

The optical signal output of the light emitting diode 12xa at wavelength λ1 is sent to the multiplexer 16b via the optical fiber cable 9a. This optical fiber cable 9a is accommodated in the same 0PGW 19ab as the optical fiber cable 110b.

Further, the optical signal of wavelength λ2 from the light emitting diode +2b is sent to the multiplexer 16b via the optical fiber cable 9b,
After being multiplexed with the optical signal of wavelength λ1 from the aforementioned light emitting diode 12xa, it is sent to the multiplexer 16c via the optical fiber cable 17bc. This optical fiber cable 17bc is accommodated in the same 0PGWI9bc as the aforementioned optical fiber cable 110b. light emitting diode 1
The optical signal of wavelength λ3 of 2c is sent to the multiplexer 16c via the optical fiber cable 9c, and is combined with the optical signals of wavelengths λ1 and λ2 sent via the aforementioned optical fiber cable +7bc. It is provided at the detection point +40d via the fiber cable 17cd and sent to the multiplexer 14318a of the Mero transmission terminal station toob.

This optical fiber cable +7cd is accommodated in the same 0PGWI9cd as the aforementioned optical fiber cable 110b.

The optical signals with wavelengths λ1, λ2, and λ3 inputted to the demultiplexer 18a are demultiplexed into optical signals with wavelengths λ, λ2, and optical signals with wavelength λ3, and then the optical signal with wavelength λ3 is sent to the discriminator 10b. Man-powered. On the other hand, the optical signals of wavelengths λ1 and λ2 are sent to the demultiplexer 18
b, and after being demultiplexed into an optical signal with wavelength λ1 and an optical signal with wavelength λ, each optical signal is input into discriminator 1ob.

An optical signal of wavelength λ from the light emitting diode 12d is sent to the discriminator H[Ob via the optical fiber cable 9d.

The optical signal of wavelength λ3 from the light emitting diode 12Yg is sent to the multiplexer 16f via the optical fiber cable 9g. Here, this optical fiber cable 9g is accommodated in the same OPGWlQrg as the aforementioned optical fiber cable ll0c. The optical signal of the wavelength λ2 from the light emitting diode 12f is input to the multiplexer 16f via the optical fiber cable 9'', and the optical signal of the wavelength λ3 from the light emitting diode 12yg mentioned above is input to the multiplexer 16f.
After being combined with the optical signal of optical fiber cable +7e
The signal is sent to the multiplexer 16e via r. Here, this optical fiber cable 17ef is accommodated in the same 0PGWlQef as the aforementioned optical fiber cable 1lQc.

The optical signal of wavelength λ1 from the light emitting diode +2e is inputted to the multiplexer 16e via the optical fiber cable 9e, and is multiplexed with the optical signal of wavelength λ and wavelength λ3 manually input via the optical fiber cable 17er. After that, the signal is sent to the duplexer 18c of the transmission terminal station 100b via the optical fiber cable 17de.

Here, this optical fiber cable 17de is the same 0PGW19de as the aforementioned optical fiber cable 110c.
contained within.

The optical signals with wavelengths λ1, λ2, and λ3 input to the demultiplexer 18c are demultiplexed into optical signals with wavelengths λ2 and λ3 and optical signals with wavelength λ1, and then the optical signal with wavelength λ1 is manually input to the discriminator 10b. Ru. On the other hand, optical signals of wavelengths λ2 and λ3 are processed by a demultiplexer 18d.
After being split into an optical signal with wavelength λ and an optical signal with wavelength λ3, each optical signal is input into discriminator 10b.

Therefore, an optical signal proportional to the current amplitude of the overhead ground wire 6 detected by each of the CTs 8a to 8g at the detection points 140a to 140g is input to the discrimination device 10b of the transmission terminal station toob. In the discrimination device 10b, for example, light emitting diodes l2 of the two adjacent completed CTs are detected along the overhead ground wire 6 of the power transmission system 210.
The phase difference between the two optical signals output from Xa and +2b is measured, and when the phase difference becomes 180°, it is determined that an accident has occurred between the detection points 140a and 14Ob, even though the CT is completed above. be done. That is, in the discriminator Job of FIG. 1, the detection points 140a to 140
It is possible to determine the interval between adjacent detection points of g, that is, the accident interval between six detection points.

Accident information indicating whether the above sections and "" are accident sections is transmitted from the discriminating device 10b to the optical transmission device 20b.

The optical transmission device 20b is connected to adjacent transmission terminal stations, for example, in the case of the transmission terminal station 100b, the transmission terminal stations 100a and 10
The optical signal containing the accident information transmitted from 0c is received, and the optical signal is further manually inputted from the discriminator 10b to the own station [00b, including the accident information, as an optical signal,
The optical path signals are transmitted to adjacent transmission terminal stations 100c and 100a, respectively. Note that if there is no accident information for the own station toob, the optical signal is directly transmitted to the adjacent transmission terminal station 100c.
and 100a. Therefore, at the transmission terminal station toob, the optical signal of wavelength λ1 received from the transmission terminal station 100a via the optical fiber cable 1lob and the multiplexer/demultiplexer 120d is received by the optical transmission device 20b. After the received optical signal is once demodulated into a data signal, the optical signal of wavelength λ is modulated with a data signal that includes the accident information of the own station 100b in the accident information of other transmission terminal stations. This modulated optical signal of wavelength λ1 is sent to a multiplexer/demultiplexer! 20e and the transmission terminal station 1on via the optical fiber cable 110c.
e (transmitted.

On the other hand, an optical signal of wavelength λ2 received from transmission terminal station 5i00c via optical fiber cable 1IOc and multiplexer/demultiplexer 120e is received by optical transmission device 20b. After the received optical signal is once demodulated into a data signal, accident information from other transmission terminal stations is transmitted. The optical signal of wavelength λ2 is modulated with a data signal including the accident information of the own station +00b. This modulated optical signal of two wavelengths λ2 is transmitted to the transmission terminal station 1 via the demultiplexer/multiplexer 120d and the optical fiber cable 1]Ob.
00a.

Incidentally, the optical fiber cable 1IOb has the above-mentioned l core.

I I Oc, I 7bc, I 7e4 use 2-wave optical multiplex cable, and 1-core optical fiber cable 1
7cd.

17de uses a 3-wave optical multiplex cable.

Although the configuration of the transmission terminal station toob has been described above, the other transmission terminal stations 100a, 100c, and 100d are similarly configured.

FIG. 2 is a diagram showing the overall system configuration of the power transmission line fault area locating system of FIG. 1.

In FIG. 2, a mask station 200a, a transmission terminal station 100a, a transmission terminal station 100b, and a transmission terminal station 10 (lc) are arranged at a predetermined distance along a power transmission system 210.

A transmission terminal station 100d and a mask station 200b are provided in this order, and between each station there is a 2-core network provided along the power transmission system 210.
The PCW is connected using an optical fiber cable 110, and information is transmitted in both directions between each station using an optical wavelength multiplexing method.

Mask stations 200a and 200b (hereinafter collectively referred to as 200) are monitoring stations in this system, and each transmission terminal station 100a, 100b, +00c and 100(
j (hereinafter collectively referred to as 100) locates the accident section using the previous CT installed on the overhead ground wire 6 of the power transmission system 210 as shown in FIG. 1, and outputs the accident information. Mask stations 200a and 200b are respective transmission terminal stations 100a and 100b.

Accident information from optical fiber cables l1Oa, lIO), IIOc, IIO
d and ll0e and mask stations 200a, 20
Display on the monitoring display device of 0b.

Each transmission terminal station 100a, +00b, 1ooc and 100
d transmits accident information obtained by the above-mentioned accident detection system using a plurality of optical Ts installed at a plurality of detection points such as steel towers in the power transmission system 210 to the adjacent mask station 2.
00a, 200b or another transmission terminal station +00 via a demultiplexer/multiplexer and an optical fiber cable, an optical signal containing accident information is received from an adjacent transmission terminal station 100, The transmission terminal station 100 or mask station 200 transmits an optical signal containing the received accident information of other transmission terminal stations 100 together with the above-mentioned accident information of its own station.

A single optical fiber cable is used between the master station 200 and the transmission terminal station 100 and between each transmission terminal station 100.
lOa, I job, I IOC, 100 (1 & 10
0e, and the wavelength λ3. l) Two-way communication is performed by using the λ2 optical multiplex transmission system, and the specific data transmission procedure is as follows.

6 Master IM2 (] Oa and 200b generate synchronization signals that are synchronized with each other, and in the first cycle of the synchronization signal, the mask station 200a sends out an optical signal of wavelength λ1 in the direction toward the master station 200b, while the synchronization signal In the second cycle, the mask station 200b sends out an optical signal of wavelength λ2 in the direction toward the mask station 200a, and the first cycle and the second cycle are repeated.

By configuring as described below, each transmission terminal station 1
Information regarding the accident section detected at 00a, IOOb, lOOc, and 100d is transmitted to the master stations 200a and 200b, and the master stations 200a and 200b
In this way, it is possible to know which detection points are located in the accident section within the section.

Wavelength λ1 in the above embodiment. ^, λ3 is, for example, 0.
They are 85 μm, 1.3 μm, and 1.5 gm.

FIG. 3 is a circuit diagram of a previous-generation CT used at the boundary points of each detection section of the power transmission line accident section locating system of FIG. 1. The pilot type CT is a circuit for converting the secondary current of the overhead ground wire 6 detected by the current transformer 8 into two optical signals.

In FIG. 3, the core 8c is arranged so that the center of the annular core 8c passes close to and without contact with the overhead ground wire 6.
c is provided. The secondary winding of the current transformer 8 is wound around the core 8C in the same direction as the core 8C, and the overhead ground wire 6 is connected to the core 8C.
Let A be the + side terminal of the secondary winding of each current transformer 8 when the current transformer 8 is passed through C, and B be the − side terminal.

13 is a discharge gap element, which connects terminals A-B of current transformer 8.
The terminal A is connected to one end of the bidirectional Zener diode 14 and the current limiting resistor + via the current limiting resistor I5a.
5b, while the other end of the current limiting resistor +5b is connected to the cathode of the light emitting diode 12x and the anode of the light emitting diode 12Y. The terminal a is a common terminal, and is connected to the other end of the bidirectional Zener diode 14, the anode of the light emitting diode 12x, and the light emitting diode 12.
connected to the cathode of y. Light emitting diode +2x, 1
The optical signals emitted by 2y are connected to optical connectors 13x and 13x, respectively.
I3y and fiber optic cable 9X.

The signal is transmitted to the discrimination circuits fox and lOy via 9y.

In addition, as a characteristic of the current transformer 8 in FIG.
A voltage that saturates is selected so that even if the negative current changes variously, the secondary voltage (peak value) does not change much and the signal rises steeply.

FIG. 4 is a diagram showing waveforms of various parts of the predecessor 〇T of FIG. 3.

In FIG. 4, when the saturation level of current transformer 8 is smaller than the amplitude of the primary current, the waveform of the secondary voltage of current transformer 8 becomes a waveform whose amplitude is limited by the magnetic saturation. moreover,
The waveform of the output voltage of the Zener diode I4 rises to the Zener diode 14 and becomes an approximately rectangular waveform whose amplitude is limited. Next, only the positive voltage of the output voltage of the Zener diode 1 is taken out and applied to the light emitting diode 12.
x and is converted into an optical signal proportional to the amplitude of the output voltage. On the other hand, only the negative voltage of the output voltage of the Zener diode 14 is taken out, drives the light emitting diode +2y, and is converted into an optical signal proportional to the amplitude of the output voltage. Each of the above optical signals is connected to an optical connector 13x, ! 3y and the discriminator 10X, I via the optical fiber cables 9X, 9Y.
Output to OY.

By configuring as shown in Figure 3, even when the secondary current of the overhead ground wire 6 flowing to the current transformer 8 is small, two light emitting diodes can be connected in parallel in opposite directions to one current transformer. Thus, two optical signals having a phase difference of 180° can be obtained. Each completed CT must be connected to the same discrimination device 10K.
By making the direction of the light emitting diodes the same with respect to the A-B output terminals of the current transformer 8, it is possible to make each secondary current of the overhead ground wire 6 in the section where no accident has occurred to be in the same phase. . On the other hand, when an accident occurs, the same discriminating device 10
The phase difference between each optical signal output to X is 180 degrees, making it easy to determine an accident.

Hereinafter, the completed CT shown in FIG. 3 will be referred to as a double light emitting diode type completed C'F, and the completed CT in which a conventional light emitting diode is emitted to obtain an optical signal will be referred to as a single light emitting diode type optical CT.

As shown in the embodiment of FIG.
By using the double light-emitting diode type predecessor 〇T shown in FIG. There is an advantage that C'F can be reduced by one compared to the conventional example.

In the above embodiment, there are four transmission terminal stations, but it can be configured with more or fewer transmission terminal stations. Also, 1
It is possible to locate the fault section between six detection points at the transmission terminal station, but it is necessary to increase the number of optical fiber cables between each completed By increasing the number of wavelengths, it is possible to locate areas beyond the above accident area.

Furthermore, the above embodiments can be easily applied to power distribution lines.

[Effects of the Invention] As described in detail above, according to the present invention, at the boundary between two adjacent fault detection sections, a common gap of 1 is provided for both detection sections.
The advantage is that by connecting two light-emitting guides in opposite directions to one fault current detection current transformer, the number of current transformers used at the boundary point can be reduced by one compared to the conventional example. There is.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing the configuration of a transmission terminal station of a transmission line fault section locating system showing an embodiment of the present invention, and Fig. 2 shows the overall structure of the transmission line 1 fault section locating system shown in Fig. Figure 3 is a circuit diagram of the double light-emitting diode type optical current transformer used in the transmission line accident area location system shown in Figure 1. Figure 4 is a waveform diagram of each part of the optical current transformer shown in Figure 3. , FIG. 5 is a block diagram showing the configuration of a transmission terminal station in a conventional power transmission line fault section locating system, and FIGS. 6 and 7 are circuit diagrams of conventional optical current transformers. 6... Overhead ground wire, 8a, '8b, 8c, 8d, 8e, 8f, 8g, 8b"
, 81"--Current transformer (CT), 9a, 9b, 9c, 9d, 9e, 9f, 9g, 9a",
9b", 9f'. 9g'...Optical fiber cable, 10b...Discrimination device, +2xa, 12b, 12c, 12d, 12e, 121'
, 12yg. 12xa', 12b'', I 2f', I 2yg
””Light emitting diode, 17bc, 17cd, I 7de, I 7ef-
Optical fiber cable, 20b... Optical transmission device, 100a, l00b, l00c, 100d - Transmission terminal station, 110a, I I Ob, l I Oc, 110d, l
l0e - fiber optic cables, +20a, 120b, 120c, 120d, 120e. 120 (120g, I 20h, I 20i, I 20
j-multiplexer/demultiplexer, 140a, I 40b, I 40c, I 40d, 14
0e. 140r, 140g, 140a", 140b", 140
f'. 140g'...Detection point, 200a, 200b--Master station, 210...Power transmission system, A, A', A-...Detection section.

Claims (1)

[Claims] (1) Within the same fault detection section, light emitting diodes are installed in the same polarity direction on the output sides of multiple fault current detection current transformers wound around the overhead ground wire of the power transmission and distribution line, and
In the adjacent fault detection sections, a light emitting diode is connected to the output side of each current transformer in a direction opposite to the above polarity, and at the boundary between the two adjacent fault detection sections, one fault current shared by both detection sections is connected. 1. A power transmission and distribution line fault section locating system, characterized in that a detection current transformer is provided and two light emitting diodes oriented in opposite directions are connected to the shared current transformer.