JP2000166081A - Power system protective relay device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the efficiency of a recovery work by determining the specific section where an accident has occurred for display. SOLUTION: A computing device 115 of a master terminal relay device 11 conducts differential computation of the current in a self-terminal electric station 6 of a transmission line 1 extracted from current transformers 51a, 51b, and the current in a mated terminal electric station transmitted through an optical fiber 2 from a plurality of shave terminal relay devices, determines a specific section where an accident has occurred, and operates relays 121, 122 for displaying accident of a specific section by an output part 116.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power system protection relay device for detecting an abnormality occurring in a power system of a transmission line to be protected and operating a circuit breaker to protect the power system.

[0002]

2. Description of the Related Art FIG. 16
2, No. 10 is a diagram illustrating a configuration of a transmission line protection system in a case where the multi-terminal transmission line protection system based on optical fiber transmission shown in US Pat. In the figure, reference numeral 1 denotes a transmission line of a power system in a specific section A and a specific section B in a protection section, which is illustrated by a single line, but is configured by three-phase lines of A phase, B phase, and C phase. I have. 6 is a local electric station provided on one side of the specific section A of the transmission line 1, 7 is a counter end electric station provided on the other side of the specific section A of the transmission line 1 and one side of the specific section B of the transmission line 1, Reference numeral 8 denotes a partner electrical station provided on the other side of the specific section B.

[0006] In FIG. 6, reference numeral 10 denotes a local terminal 6.
This is a master relay device that is installed in a computer and performs digital relay calculations. Reference numerals 20, 30, and 40 are installed at the counterpart electrical stations 7 and 8, respectively, perform a digital relay operation, transmit current data to the master relay device 10, and receive a transfer interruption command from the master relay device 10. This is a slave relay device that trips (trips) the mating circuit breakers 62a, 62b, 64a, 64b.

Further, in FIG. 6, 51a, 51b,
52a, 52b, 53a, 53b, 54a, 54b are current transformers for extracting and measuring current, and 61a, 61
b denotes a self-interrupting circuit breaker for interrupting the transmission line 1 on the side of the local electric station 6; Container, 2
Is the parent relay device 10, the child relay devices 20, 30, and 4
This is an optical fiber for transmitting data that connects between 0s in a loop.

FIG. 7 is a block diagram showing the configuration of the master relay device 10. As shown in FIG. In the figure, 101a and 101b are analog filters, 102a and 102b are sample and hold circuits that hold data, 103 is a multiplexer circuit that switches input channels, 104 is an A / D conversion circuit that performs analog / digital conversion, and 105 is input data. An arithmetic unit for performing a relay operation by using the circuit breaker 106
a, an output unit for outputting a trip command for tripping 61b; 107, an optical / electrical converter for converting data transmitted via the optical fiber 2; 108, a serial / parallel converter; 109, a parallel / serial converter The converter 110 is an electro-optical converter for converting data transmitted through the optical fiber 2. Reference numeral 120 denotes a relay for indicating that an internal accident has occurred in the transmission line 1 in the specific section A or the specific section B in the protection section.

FIG. 8 is a block diagram showing the structure of the slave relay device 20 except that a relay 120 for indicating that an internal accident has occurred is removed from the structure of the master relay device 10 shown in FIG. And analog filters 201a and 201b, a sample hold circuit 202
a, 202b, multiplexer circuit 203, A / D conversion circuit 204, arithmetic unit 205, output unit 206, optical / electrical converter 207, serial / parallel converter 208, parallel / serial converter 209, electric / optical converter 210 It consists of. The configurations of the slave relay devices 30, 40 are the same as those in FIG.

[0007] As described above, the power system protection relay is
The master relay device 10 and the slave relay devices 20, 30,
40, the transmission line protection system comprises the power system protection relay and current transformers 51a, 51b, 52
a, 52b, 53a, 53b, 54a, 54b, own-end breakers 61a, 61b, mating-end breakers 62a, 62b, 6
4a, 64b and the optical fiber 2.

Next, the operation will be described. FIG. 9 is a flowchart showing the processing of the power system protection relay device. In step ST11, the parent-end relay device 10 and the child-end relay devices 20, 30, and 40 convert the current of the transmission line 1 of the power system into current transformers 51a, 51b, 52a, and 5, respectively.
2b, 53a, 53b, 54a, 54b,
The slave terminal relay devices 20, 30 and 40 transmit the extracted slave terminal current data via the optical fiber 2 to the master terminal relay device 10.
The master relay device 10 performs a differential operation based on the extracted self-terminal current data and the transmitted slave terminal current data.

The master relay device 10 includes a current transformer 51.
DC components and harmonic components are removed by the analog filters 101a and 101b from the self-end currents extracted from the a and 51b.
Sample and hold circuits 102a, 102
02b, and sequentially switches the channels of the multiplexer circuit 103 to convert the analog amount into an A / D conversion circuit 104.
To make it possible to perform digital operations. Slave end relay device 2
0, 30, 40 are also analog filters 201a, 201
b, the sample and hold circuits 202a and 202b, the multiplexer circuit 203, and the A / D conversion circuit 204 perform the same processing.

The master relay device 10 and the slave relay devices 20, 30, and 40 installed at each end of the transmission line 1 are connected in a loop by an optical fiber 2, and the current data at each end is , And time-division serial transmission is performed via the optical fiber 2. First, an empty data frame in which current data has not been written is transmitted from the master relay device 10 to the slave relay device 20.

In the slave relay device 20, the received signal is optically / electrically converted by the optical / electrical converter 207, and the converted signal is serial / parallel converted by the serial / parallel converter 208. The slave terminal current data extracted from the current transformers 52a and 52b is written into the frame F1 of the relay device 20, and the parallel / serial converter 20
9, the parallel / serial conversion is performed, the electrical-optical converter 210 performs the electrical-optical conversion, and the data frame is transferred to the slave relay device 30.

Hereinafter, the same operation is performed in the slave relay devices 30 and 40. In the slave relay device 30, the current transformers 53a and 53b extract the frame F2 for the slave relay device 30 in the data frame. The child terminal current data is written, and the child terminal relay device 40 writes the child terminal current data extracted from the current transformers 54a and 54b into the frame F3 for the child terminal relay device 40 in the data frame, and writes all the child terminal relays. The data frame in which the child terminal current data is written in the devices 20, 30, and 40 is transmitted to the master relay device 10.

The arithmetic unit 105 of the master relay device 10 includes:
These transmitted child terminal current data and the current transformer 5
A current differential operation is performed using own-end current data extracted from 1a and 51b.

In step ST12 of FIG. 9, the arithmetic unit 105 of the master relay device 10 determines whether or not an internal accident has occurred within the protection zone based on the arithmetic result. If the self-end current data is different from any of the child terminal current data and it is determined that the internal accident is within the protection section, in step ST13, the arithmetic unit 105 supplies the trip output from the output unit 106 to thereby control the self-end breaker 61a. , 61b, and writes the data for transfer interruption into the frame for the parent-end relay device in the data frame, and transmits the data to the child-end relay devices 20, 30, and 40 to transmit the data to the slave-end relay device 62.
a, 62b, 64a, and 64b are operated.

Further, at this time, in step ST14, the output unit 106 operates the relay 120 in accordance with the instruction of the arithmetic unit 105, and an internal accident occurs in the transmission line 1 in the specific section A or the specific section B in the protection section. To be displayed.

[0016]

Since the conventional power system protection relay is constructed as described above, it detects only the accident of the power system in the protection section and shuts it down, so that only the protection of the power system is performed. The purpose of the present invention is to display only a relay phase of a failure phase or a short-circuit / ground fault by the relay 120. Therefore, even if a plurality of maintenance departments exist in the power system, whether an accident has occurred in the specific section A or a specific section There was a problem that it was not possible to determine whether the error occurred in B, and the efficiency of the recovery work was low.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and a specific section in which an accident has occurred in a power system to be protected is determined and displayed at a low cost, so that restoration work can be performed. It is an object of the present invention to obtain a power system protection relay capable of realizing efficiency.

[0018]

According to the present invention, there is provided an electric power system protective relay comprising: a power transmission line in a protection section formed by a plurality of specific sections between a self-end electric station and a plurality of opposite end electric stations; In a system for protecting a system by shutting down in the event of an accident, a plurality of slave terminals installed at the plurality of counterpart electric stations and transmitting current data taken out of a current transformer of the counterpart electric station. An accident occurs in the protection section due to a relay device, current data taken from a current transformer of the local terminal and installed in the local terminal, and current data transmitted from the plurality of child terminal relay devices. In addition to detecting that the power system has been shut down, the power system is cut off, and a differential operation is performed between the current data extracted from the local terminal and the current data transmitted from each of the slave terminal relay devices. Those having a parent edge relay apparatus for displaying to determine the specific period.

The power system protection relay device according to the present invention comprises:
The master-end relay device obtains the scalar sum of the current flowing into and out of the specific section as the suppression amount, taking into account the CT saturation error of the current transformer of the other end electric station and the current transformer of the own end electric station,
The specific section in which the accident has occurred is determined and displayed.

[0020] The power system protection relay device according to the present invention comprises:
The master-end relay device determines the maximum value of the current flowing into and out of the specific section as a suppression amount, and takes into account the CT saturation error of the current transformer of the other end electric station and the current transformer of the own end electric station. The generated specific section is determined and displayed.

The power system protection relay device according to the present invention comprises:
Protecting the power system of a transmission line in a protection section consisting of a plurality of specific sections between a local terminal and a plurality of partner terminals by shutting down in the event of an accident. It is installed at the other party electric station, transmits the current data taken out from the current transformer of the other party electric station, and transmits the current data taken out of the current transformer of the other party electric station and the voltage transformer of the other party electric station. A plurality of slave relay devices for comparing the phases of the voltage data taken out from the current transformer and transmitting a direction discrimination bit, and current data taken out of a current transformer installed in the own end electric station and taken out of the current end electric station. And, based on the current data transmitted from the plurality of slave relay devices, detecting that an accident has occurred in the protection section and shutting down the power system. The al transmitted direction discriminating bit, those having a parent edge relay apparatus for displaying to determine the specific section in which the accident has occurred.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below. Embodiment 1 FIG. FIG. 1 is a block diagram showing a configuration of a master relay device 11 in a power system protection relay device according to a first embodiment, and a conventional master relay device 10 shown in FIG.
And relays 121 and 122 for displaying the specific sections A and B in which the accident has occurred. In FIG. 1, two relays 121 and 122 are added, but it is sufficient to add relays of the number of the specific section in the protection section.

In FIG. 1, reference numeral 115 denotes a calculation for realizing a relay function for detecting a fault in a specific section, in addition to a calculation for realizing a relay function for detecting a fault in a conventional protection section. Is an arithmetic unit that performs
Is an output section for supplying a trip output for operating the own-end circuit breakers 61a and 61b and an output for operating the relays 120, 121 and 122. Other configurations are the same as those of the conventional master relay device 10 shown in FIG. It is equivalent to the one shown.

The construction of the slave relay devices 20, 30, and 40 is the same as that shown in FIG. 8, and the construction of the transmission line protection system is the same as that of the master relay device 10 shown in FIG.
Is replaced with the parent end relay device 11.

FIG. 2 is a diagram for explaining the principle of determining a specific section in which an accident has occurred. The self-end currents extracted from the current transformers 51a, 51b are represented by i1, current transformers 52a, 52
If the child terminal current extracted from b is i2, that is, the currents flowing into and out of the specific section A are i1 and i2,
According to Kirchhoff's first law, the accident point f in the specific section A
When 1, i1１i2, so that the difference current id becomes id = i1−i2 ≠ 0.

On the other hand, when the fault point f2 is outside the specific section A, i1 = i2, so that the difference current id is id = i1-i2 = 0.

That is, the self-end current i of the parent end relay device 11
Assuming that the tap value indicating the minimum operation sensitivity is K based on 1 and the slave terminal current i2 of the slave terminal relay device 20, when id = i1−i2 ≧ K (1), it is determined that the accident is within the specific section A, and id = I1-i2 <K (2) It can be determined that the accident is outside the specific section A. Here, as the value of the tap value K, a value of about 1/3 of the minimum fault current at the time of the fault in the section is used.

The accident in the specific section B and the accident outside the specific section B can be determined in the same manner as the above principle.

Next, the operation will be described. FIG. 3 is a flowchart showing processing of the power system protection relay device according to Embodiment 1. The processes from steps ST21 to ST24 are performed in steps ST11 to ST1 shown in FIG.
This is the same as the processing up to 4.

In step ST25, the arithmetic unit 115 of the master relay device 11 sets the current transformers 51a and 51b.
Own-end current data extracted from the
The differential operation is performed based on the slave terminal current data taken out of the current transformers 52a and 52b transmitted by the above.

In step ST26, the arithmetic unit 11
5 determines whether or not the accident is within the specific section A according to the equations (1) and (2) in the principle of the specific section determination based on the calculation result. Then, when it is determined that the accident is in the specific section A, in step ST27, the arithmetic unit 11
In response to the instruction of 5, the output unit 116 operates the relay 121 to display that the accident is within the specific section A.

If it is determined in step ST26 that the accident is outside the specific section A, in step ST28, the arithmetic unit 115 outputs the child terminal currents extracted from the current transformers 53a and 53b transmitted by the child end relay device 30. The differential operation is performed based on the data and the slave terminal current data extracted from the current transformers 54a and 54b transmitted by the slave terminal relay device 40.

In step ST29, the arithmetic unit 11
5 determines, based on the calculation result, whether or not the accident is within the specific section B according to the equations (1) and (2) in the principle of the specific section determination. If it is determined that the accident is in the specific section B, in step ST30, the arithmetic unit 1
In response to the instruction of No. 15, the output unit 116 operates the relay 122 to display the fact that the accident is in the specific section B.

As described above, according to the first embodiment, in addition to the conventional relay function for detecting an accident in a protection section, the master relay device 11 can be easily implemented without largely changing the hardware configuration. In addition, it is possible to obtain a power system protection relay device that has a relay function for determining a specific section where an accident has occurred and that can achieve an efficient recovery operation at low cost.

Embodiment 2 The configuration of the master relay device 11 in the power system protection relay device according to the second embodiment is the same as the configuration of FIG. 1 in the first embodiment, and the configurations of the slave relay devices 20, 30, and 40 are also conventional. The configuration is the same as that shown in FIG. 8, and the configuration of the transmission line protection system is also the same as that of the first embodiment.

The second embodiment differs from the first embodiment in the principle of the specific section determination. Current transformers 51a, 51
b, 52a, and 52b,
Various error currents such as T saturation may be considered. Therefore, the scalar sum of the currents extracted from the current transformers 51a, 51b, 52a, and 52b, that is, the currents i1 and i2 flowing into and out of the specific section A is obtained as the suppression amount ir according to the following equation. ir = | i1 | + | i2 | (3)

The current transformers 51a, 51b, 52
When a ratio coefficient indicating an allowable ratio between the input current and the output current in the specific section A of a and 52b is K1 and a tap value indicating the minimum operation sensitivity is K2, id = i1−i2 ≧ K1 * ir + K2 (4) It is determined that the accident is within the specific section A. When id = i1−i2 <K1 * ir + K2 (5), it can be determined that the accident is outside the specific section A. Here, a value such as 1/9 is used as the ratio coefficient.

An accident within the specific section B and an accident outside the specific section B can be determined in the same manner as the above principle.

Next, the operation will be described. Embodiment 2
Is the same as that shown in FIG. 3 of the first embodiment. The processing from steps ST21 to ST24 is the same as the conventional processing shown in FIG.
Is the same as the processing from step ST11 to ST14 shown in FIG.

In step ST25, the arithmetic unit 115 of the master relay device 11 sets the current transformers 51a and 51b.
Own-end current data extracted from the
The differential operation is performed based on the slave terminal current data taken out of the current transformers 52a and 52b transmitted by the above.

In step ST26, the arithmetic unit 11
5 is based on the above calculation results and takes into account various error currents such as CT saturation using the scalar sum of the current flowing into and out of the specific section A as a suppression amount, according to the above equations (3) to (5).
It is determined whether or not the accident is within the specific section A. Then, when it is determined that the accident is in the specific section A, in step ST27, the output unit 116 operates the relay 121 according to the instruction of the arithmetic unit 115 to display the fact that the accident is in the specific section A.

If it is determined in step ST26 that the accident is outside the specific section A, in step ST28, the arithmetic unit 115 outputs the child terminal currents extracted from the current transformers 53a and 53b transmitted by the child end relay device 30. The differential operation is performed based on the data and the slave terminal current data extracted from the current transformers 54a and 54b transmitted by the slave terminal relay device 40.

In step ST29, the arithmetic unit 11
5 determines, based on the calculation result, whether or not the accident is within the specific section B according to the above equations (3) to (5). If it is determined that the accident is in the specific section B, the process proceeds to step S
At T30, the output unit 116 operates the relay 122 in response to an instruction from the arithmetic unit 115 to display that the accident is in the specific section B.

As described above, according to the second embodiment, in addition to the conventional relay function for detecting an accident in the protection section, the parent relay device 11 calculates the scalar sum of the current flowing into and out of the specific section. Considering the CT saturation error as the suppression amount, it has a relay function for easily and inexpensively determining the specific section where the accident has occurred without greatly changing the hardware configuration, and displays which specific section of the accident it is. Thus, an effect is obtained that a power system protection relay device that can realize a more efficient recovery operation can be obtained.

Embodiment 3 The configurations of the slave relay devices 20, 30, and 40 and the configuration of the transmission line protection system according to the third embodiment are the same as those of the first embodiment. Also, the configuration of the master relay device 11 in the power system protection relay device according to the third embodiment is the same as the configuration of FIG. 1 in the first embodiment, but the specific section where the accident has occurred in the second embodiment. This is a modification of the suppression amount ir used for the determination.

The current transformers (51a, 51b), (52
a, 52b), the currents i1, i2, ie,
The larger one of the currents i1 and i2 flowing into and out of the specific section A is obtained as the suppression amount ir by the following equation. ir = max [| i1 |, | i2 |] (6)

Assuming that the ratio coefficient is K3 and the tap value is K4, if id = i1−i2 ≧ K3 * ir + K4 (7), it is determined that the accident is within the specific section A, and id = i1−i2 <K3 * ir + K4 ( In the case of 8), it can be determined that the accident is outside the specific section A.

Next, the operation will be described. Embodiment 3
Is also the same as that shown in FIG. 3 of the first embodiment. However, when determining whether or not the accident is within the specific section A in step ST26 and determining whether or not the accident is within the specific section B in step ST29, the larger of the current flowing into and out of the specific section is suppressed. The difference is that the determination is made according to the above equations (6) to (8), which are obtained as quantities and take into account various error currents such as CT saturation.

As described above, according to the third embodiment, in addition to the conventional relay function for detecting an accident in the protection section, the parent end relay device 11 determines whether the current flowing into or out of the specific section is larger. Considering the CT saturation error as the suppression amount, it has a relay function for easily and inexpensively determining the specific section where the accident has occurred without greatly changing the hardware configuration, and displays which specific section of the accident it is. Thus, an effect is obtained that a power system protection relay device that can realize a more efficient recovery operation can be obtained.

Embodiment 4 FIG. 4 is a block diagram showing a configuration of the slave terminal relay device 21 in the power system protection relay device according to the fourth embodiment. Reference numeral 71 denotes a voltage transformer that extracts the voltage of the transmission line 1 at the counterpart electric station 7, 20
Reference numerals 1c and 202c denote analog filters and sample-and-hold circuits for processing the voltage extracted from the voltage transformer 71. Other configurations are the same as the configuration of the conventional relay device 20 shown in FIG. That is, the slave relay device 21 illustrated in FIG. 4 has a function as a directional relay. Other slave relay devices 31 and 4
1 has the same configuration.

The configuration of the master relay device 11 in the power system protection relay device according to the fourth embodiment is the same as the configuration of FIG. 1 in the first embodiment, and the configuration of the transmission line protection system is the same as that of the conventional transmission line protection system. Master relay device 10 in FIG.
Is replaced with the master relay device 11 and the slave relay device 2
This is equivalent to a device in which 0, 30, and 40 are replaced with slave terminal relay devices 21, 31, and 41.

The method of the directional relay used for the specific section determination is shown in, for example, P127 to P131 of "Protective Relay Engineering" issued by the Institute of Electrical Engineers of Japan in 1981. That is, if an accident occurs in a specific section, the fact that the direction of the accident current is the same as the voltage is used.

Next, the operation will be described. FIG. 5 is a flowchart showing the processing of the power system protection relay device according to the fourth embodiment. The processing of steps ST41 to S44 is the same as that of steps ST11 to ST14 in FIG.
The processing is the same as that described above.

In step ST45, the slave relay device 21 compares the phases of the currents taken out of the current transformers 52a and 52b and the voltage taken out of the voltage transformer 71. The direction discriminating bit "1" is written in the frame F1 for the slave terminal relay device 21, and if not in the same direction, the direction discriminating bit "0" is written and transmitted in the frame F1. Similarly, the slave relay devices 31 and 41 also transmit the direction determination bits, and the master relay device 11 receives the direction determination bits transmitted from the slave relay devices 21, 31 and 41.

In step ST46, if the direction discriminating bit transmitted from the slave relay device 21 is "1", the arithmetic unit 115 of the master relay device 11 determines that the specific section A
It is determined that the accident is within the range, and in step ST47,
The output unit 116 of the master relay device 11 is
The display of the accident in the specific section A is output according to the instruction, and the relay 121 is operated.

In step ST46, if the direction determination bit transmitted from the slave relay device 21 is "0", the arithmetic unit 115 of the master relay device 11 determines that the accident is outside the specific section A. In step ST48, the arithmetic unit 115 of the master relay device 11 determines that the direction determination bit transmitted from the slave relay device 31 or 41 is "".
If 1 ”, it is determined that the accident is in the specific section B, and in step ST49, the output unit 116 of the master relay device 11 outputs an accident display in the specific section B in accordance with an instruction from the arithmetic unit 115, The relay 122 is operated.

As described above, according to the fourth embodiment, the slave relay devices 21, 31, and 41 are provided with the function of the directional relay for detecting the directions of the voltage and current at the time of the accident, and The direction discriminating bit is transmitted, and the parent end relay device 11 can easily and inexpensively transmit the transmitted direction discriminating bit without significantly changing the hardware configuration, in addition to the relay function of detecting an accident in the protection section. Has a relay function to determine the specific section where the accident has occurred, and by displaying which specific section is the accident, it is possible to obtain a power system protection relay device that can realize more efficient restoration work. Is obtained.

[0058]

As described above, according to the present invention, the master relay device performs a differential operation on the current data taken out of the local terminal and the current data transmitted from each slave relay device. By judging and displaying the upper fixed section where the accident has occurred, there is an effect that it is possible to obtain a power system protection relay device capable of realizing more efficient restoration work.

According to the present invention, the master-end relay device is provided with a scalar for the current flowing into and out of the specific section in consideration of the CT saturation error of the current transformer at the counterpart electric station and the current transformer at the own-end electric station. By judging and displaying the specific section where the accident has occurred based on the suppression amount based on the sum, there is an effect that it is possible to obtain a power system protection relay device that can realize more efficient restoration work.

According to the present invention, the master relay device determines the maximum amount of the current flowing into and out of the specific section in consideration of the CT saturation error of the current transformer at the counterpart electric station and the current transformer at the own terminal electric station. By judging and displaying the specific section in which the accident has occurred based on the suppression amount based on the value, there is an effect that it is possible to obtain a power system protection relay device that can realize more efficient restoration work.

According to the present invention, the plurality of slave relay devices compare the phases of the current data extracted from the current transformer at the counterpart electric station and the voltage data extracted from the voltage transformer at the counterpart electric station. By transmitting the direction determination bit, the master relay device determines and displays the specific section where the accident has occurred based on the direction determination bits transmitted from the plurality of slave relay devices, thereby improving the efficiency of the recovery work. There is an effect that a feasible power system protection relay device can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a master relay device in a power system protection relay device according to Embodiments 1, 2, 3, and 4 of the present invention.

FIG. 2 is a diagram illustrating the principle of specific section determination according to the first, second, and third embodiments of the present invention.

FIG. 3 is a flowchart showing processing of a power system protection relay device according to Embodiments 1, 2, and 3 of the present invention.

FIG. 4 is a block diagram showing a configuration of a slave relay device in a power system protection relay device according to Embodiment 4 of the present invention.

FIG. 5 is a flowchart showing processing of a power system protection relay device according to Embodiment 4 of the present invention.

FIG. 6 is a diagram showing a configuration of a conventional transmission line protection system.

FIG. 7 is a block diagram showing a configuration of a master relay device in a conventional power system protection relay device.

FIG. 8 is a block diagram illustrating a configuration of a slave relay device in a conventional power system protection relay device.

FIG. 9 is a flowchart showing a process of a conventional power system protection relay device.

[Explanation of symbols]

1 transmission line, 6 own terminal electric station, 7, 8 other terminal electric station,
11 Parent-end relay device, 21, 31, 41 Child-end relay device, 51a, 51b, 52a, 52b, 53a, 53
b, 54a, 54b Current transformer, 71 Voltage transformer.

Claims (4)

[Claims] 1. An electric power system for protecting a power system of a transmission line in a protection section constituted by a plurality of specific sections between a local terminal and a plurality of partner terminals in the event of an accident. In the system protection relay device, a plurality of slave relay devices installed at the plurality of opposite end electric stations and transmitting current data taken out of a current transformer of the other end electric station, and installed at the own end electric station Then, based on the current data extracted from the current transformer of the own terminal substation and the current data transmitted from the plurality of slave relay devices, it is detected that an accident has occurred in the protection section and the power system is shut off. And a differential operation between the current data taken out from the local terminal and the current data transmitted from each of the slave relay devices to determine and display the specific section where the accident has occurred. Electric power system protective relay apparatus characterized by comprising a relay device. 2. The master relay device determines a scalar sum of currents flowing into and out of a specific section as a suppression amount, and considers a CT saturation error of a current transformer at a counterpart electric station and a current transformer at a self-terminal electric station. The power system protection relay device according to claim 1, wherein the specific section in which the accident has occurred is determined and displayed. 3. The master relay device determines a maximum value of a current flowing into and out of a specific section as a suppression amount, and considers a CT saturation error of a current transformer of a counterpart electric station and a current transformer of the own terminal electric station. The power system protection relay device according to claim 1, wherein the specific section in which the accident has occurred is determined and displayed. 4. An electric power to be protected by shutting down a power system of a transmission line in a protection section constituted by a plurality of specific sections between a self-end electric station and a plurality of opposite end electric stations when an accident occurs. In the system protection relay device, installed at the plurality of counterpart electrical stations, transmits current data extracted from the current transformer of the counterpart electrical station, and transmits current data extracted from the current transformer of the counterpart electrical station. A plurality of slave relay devices for transmitting a direction discrimination bit by comparing the data and the phase of the voltage data extracted from the voltage transformer at the other end electric station; and Based on the current data taken out of the current transformer at the place and the current data transmitted from the plurality of slave relay devices, it is detected that an accident has occurred in the protection section and the power system is shut off. In, the direction discrimination bits transmitted from the plurality of slave terminals relay device, the electric power system protective relay apparatus characterized by having a parent edge relay apparatus for displaying to determine the specific section in which the accident has occurred.