JPH095384A - Power system fault point locating device and fault point locating method - Google Patents

Abstract

(57) [Abstract] [Purpose] It can be realized without impairing the function of the conventional PCM relay, the equipment cost can be significantly reduced compared to the conventional technology, and the equipment cost can be greatly reduced and the equipment to the substation can be installed. To provide a fault point locator for a power system that does not require installation space. [Structure] A means 125 for sampling the voltage information of its own terminal together with the current information at the same time in the PCM carrier protection relay device 120 provided at the system end, and storing the voltage and current information in a memory, and an accident detection. At the same time, means for freezing the voltage and current information of the predetermined sampling section stored in the memory and means 332 for transmitting the frozen data of the freezing means to the arithmetic unit are provided, and the arithmetic unit also has a PCM carrier protection relay device. The means 333 for receiving the data transmitted by the transmitter and the means 511 for locating the accident point by arithmetic processing based on the received data are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is designed to detect an accident cause in an early stage when an accident occurs in a power system such as a transmission line or a substation and to restore the power system in an early stage. The present invention relates to a fault point locating method of a power system for calculating a position and a fault point locating device (fault locator).

[0002]

2. Description of the Related Art As a fault point locating device of this type that has been generally adopted in the past, a dedicated relay device or terminal for taking in voltage information and current information of both terminals of the power system at the end of the power system is known. Is provided, and the point of occurrence of the accident and the resistance at the point of the accident are calculated based on this captured information.

An outline of this conventional fault point locating device will be described with reference to FIGS. 4 to 7. FIG. 4 shows the most basic transmission line (three-phase AC parallel two-line 2).
1L in the figure is the transmission line 1
Line 2L is transmission line 2. In this case, although each transmission line is shown as a single line, each three-phase AC transmission line is formed by three-phase three-line drawing.

The length of the power transmission lines 1L and 2L is set to L ₀ (km), and when an accident such as a short circuit or a ground fault occurs on this length, the accident occurrence point and the resistance at the accident point In the figure, TR indicates transformers, and loads (not shown) are connected to these transformers, respectively. Further, ZS and ZR coupled to the transformer TR indicate neutral point ground impedances of the S-terminal transformer and the R-terminal transformer, respectively.

The CBs provided on the transmission line No. 1 line 1L and the transmission line No. 2L are circuit breakers, and are installed for each three-phase alternating current phase. Similarly, a current transformer CT is installed in each three-phase alternating current phase. This current transformer is for taking in information on the current flowing through the power transmission line into the device. PT is a transformer for taking in the voltage information of each terminal of the transmission line.

In the figure, 100 and 200 are terminals provided at the S terminal and the R terminal, respectively.
It has a memory unit capable of storing the voltage and current signals of its own terminal, the switching status signal of the circuit breaker CB, etc., and converts the signal at the same time at each terminal into a digital value by sampling the waveform of the commercial frequency every 30 degrees. It is provided with signal input units 110 and 210 having a storage function and transmission devices 150 and 250 capable of transmitting and receiving signals between both terminals.

Reference numeral 310 denotes a data transmission line between the transmission devices 150 and 250, which is used to transmit information at the S terminal and the R terminal, and is, for example, a telephone line, a microwave line, an optical communication line or the like. . Further, reference numeral 500, which is coupled to the transmission device 150, is a central device, which is a part for calculating the position of the accident point and the resistance of the accident point.

The central unit 500 includes an S terminal and an R terminal.
Information such as terminal voltage, current signals, and circuit breaker switching status signals are input, and the results of the arithmetic processing are output to a control station or a power supply command station. 320 is a data transmission line,
It is used to output the calculation processing result in the central device 500, to transmit a settling constant from a control station or a power feed command station, and to transmit a signal for monitoring whether or not there is an abnormality in the device.

FIG. 6 is a flow chart of the calculation, which is an example when a digital computer is used. In the figure, step 40 is for performing settling of system data, which is necessary for the arithmetic processing such as the value of the line length L ₀ , the line impedance matrix Z ₁₁ , Z ₁₂ ... Z ₆₆ , and other output format of the operation result. Set the data that can be input as the set value.

Step 41 shows an accident detection and data collection step. Accident detection detects the occurrence of an accident in the target system. When an accident is detected by detecting an accident, the voltage and current signals at each terminal are converted into digital data by sampling synchronized with each terminal and collected. To do.

In step 42, the type of accident is discriminated, and it is used as information for discriminating the short-circuit accident or the ground fault accident and selecting the use destination of the data collected in the previous step 41. Step 43 shows the process of selecting data. According to the accident type judged in the previous step, the data necessary for the arithmetic processing is selected from the collected data and fetched.

Step 44 is a process of creating a line voltage matrix. Based on the data input through the above steps, known numerical values are substituted into the simultaneous equations of the equation (5) to form a matrix of voltage equations. To create. Step 45 is for performing an accident phase discrimination calculation.

In step 46, the position k of the accident point, k ( _t ) at the time point t of the accident point resistances R ₁ , R ₂ ... R _E of the accident phase,
This is a step of calculating R ₁ ( _t ), R ₂ ( _t ) ... _RE ( _t ). Hereinafter, in steps 47 and 48, the correction calculation is performed as the calculation step of FIG. In step 47, the position k of the accident point calculated in step 46 for each sampling time
The average value k of ( _t ) is calculated.

Thereafter, it is assumed that the position of the accident point is at the average value k, and the calculation of step 48 is started. In step 48, the position k of the accident point is known with the average value k, so that the accident point resistances R ₁ ( _t ), R ₂ ( _t ) ...
Recalculate R _E ( _t ). Step 49 is a step of outputting the calculation result described above.

FIG. 7 shows an example of a main part relating to the structure of this apparatus. This figure shows a configuration example of the device on the S terminal side described in FIG. 4, which is a collective view of the terminal device 100 and the central device 500, which serves as a master station for other terminals.

The symbols and their operation contents will be described below with reference to FIG. Reference numeral 400 indicates a master station portion of the S terminal system. The master station 400 has a signal input section of its own terminal,
It has functions such as transmission and reception of signals from other terminals, an accident aspect identification calculation function that is the central unit, and a display function.

The contents of the master station system 400 will be further described. Reference numeral 111 is an A / D converter, which converts the voltage and current signals of the S terminal and the open / closed state signal of the circuit breaker CB into digital quantities and fetches them. Reference numeral 112 is an oscillogram, which is used for recording and displaying a signal input by the master station 400.

Reference numeral 114 denotes a memory, and the data processing unit 115 for storing the input signal, the received signal data, the transmitted signal data, etc., stores the signal data collected from each terminal.
It performs data conversion in complex number format, and detects accidents related to the presence or absence of system failures.

Reference numeral 151 is a converter for converting a signal format, for example, a U / B converter for converting a unipolar format into a bipolar format signal. Reference numeral 152 is a B / U converter that performs inverse conversion with 151. Reference numeral 153 is a signal terminal, which performs channel allocation of the data transmission path. Fifteen
Reference numeral 4 denotes a carrier device, which serves as an interface for data transmission with each counter terminal.

Reference numeral 511 denotes a computer for carrying out an accident aspect identification calculation (the computer 511 executes the solution of the equation (5) described later according to the calculation flow of FIG. 6).
Reference numeral 512 is an auxiliary computer that outputs the calculation result or monitors the system, and 513 is a CR that displays the screen.
It is a T display. Reference numeral 514 is a line printer that records data, and reference numeral 321 is a data transmission modem that connects the master station 400 to a control station, a power supply command station, or the like.

The modem 321 may be a small-scale device for each channel of the telephone line, such as when transmitting only the calculation result of the master station 400. 322 is a transport device,
This is a data transmission interface.

Here, in order to protect the power transmission line in the power transmission line protection relay device 113 when an accident occurs, A /
The D converter 111, the memory 114, and the signal converters 151 and 152 are mounted, and the peripheral device has the same equipment as the signal terminal 153 and the carrier device 154.

[0023]

In the conventional fault point locating device of the electric power system thus formed, the device configuration is similar to that of the PCM carrier protection relay device which requires high speed response in the event of an accident. This is a large-scale operation, that is, a fault location device and a PCM carrier protection relay device will be installed in the substation, and a large installation space is required. Expensive relays for detecting system faults were always needed for the fault locator on one side of the power station.

The present invention has been made in view of the above, and an object of the present invention is to locate a fault point of this kind of power system which can significantly reduce the facility cost and does not require the installation space of the device in the substation. To provide the equipment.

[0025]

That is, according to the present invention, the voltage information of its own terminal is sampled at the same time together with the current information in the PCM carrier protection relay device provided at the system end, and this voltage and current information is collected. Means for storing in the memory, means for freezing the voltage and current information of the predetermined sampling section stored in the memory when an accident is detected, and means for transmitting the frozen data of the freezing means to the arithmetic unit The device is provided with a means for receiving the data transmitted from the PCM carrier protection relay device and a means for locating an accident point by arithmetic processing based on the received data, thereby hindering the protection function of the PCM carrier protection relay device. It is intended to achieve the intended purpose without doing.

[0026]

That is, in the fault point locating device of the power system thus formed, the PCM carrier protection relay device is provided with the function of storing the voltage and current information in the memory within the sampling time. Therefore, the fault point locating device has a built-in PCM carrier protection relay device, and a dedicated device for obtaining voltage and current information does not need to be installed in the electric station. That is, the installation space for the equipment inside the substation is not required, the equipment cost can be significantly reduced compared to the conventional equipment, and the relay for detecting the system fault is a PC.
Since the relay built in the M carrier protection relay device can be used, a particularly expensive relay can be dispensed with.

[0027]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the illustrated embodiments. FIG. 1 shows an example of the configuration. The fault point and the fault point resistance are calculated when a system fault such as a short circuit or a ground fault occurs over the length of the transmission line 1L and 2L. In addition,
This calculation will be described later.

In the drawing, 120 and 130 are PCM carrier protection relays (hereinafter referred to as PC) arranged at the end of the power system.
M relay) is shown in a block diagram. Here, for the sake of convenience, the input sections of the transmission line No. 1L side and the transmission line No. 2 line 2L side are put together, but generally, the transmission line No. 1L side and the transmission line No. 2L side are each individually provided with a PCM relay. 120 and 130 are installed.

The PCM relays 120 and 130 have a constant sampling synchronization function, so that the currents I ₁ ,
I _2, voltage V, the size of the other device information (CB condition etc.), the signal input unit 121 for converting state by the sampling period of an electrical angle of 30 degrees each to the digital quantity, A / D converter 122, between the terminals It has transmission devices 155 and 156 capable of transmitting and receiving the signal of.

The adjustment of the sampling synchronization is performed by the transmission device 15
5, 156, signal terminal 157, carrier 158
And transmission line 159. In addition, the electric current of the mating terminal and the device information (CB condition, etc.) sampled for every 30 electrical degrees are transmitted and received continuously through the transmission devices 155 and 156 at a predetermined transmission speed.

In the PCM relay 120, the current and voltage information of its own terminal is converted into a digital amount through the A / D converter 122 and stored in the memory 123 in order to immediately determine a system fault such as a short circuit or a ground fault. Let On the other hand, the current information of the other terminal is received by the transmission device 156 via the transmission path 159 and stored in the memory 123.

The relay calculation unit 124 performs relay calculation based on the current and voltage of its own terminal and the current of the other terminal, and determines a short circuit or a ground fault by the operating relay. If this judgment determines that there is a system accident, DO
A trip command is given to the circuit breaker CB via 126.

The current and voltage information of its own terminal used in the relay calculator 124 is stored in the memory 125 every 30 electrical degrees, and it is judged that the data has gone through once, and the data is written again from the head address. Is considered.

When a system fault occurs, the memory 125,
The current and voltage information respectively stored in 127 is frozen, and the frozen data is transmitted by transmission lines 331, 334 such as a telephone line.
6 is transmitted. The CPU 511 in the arithmetic unit 510 uses the received data to calculate the accident point and the accident point resistance based on the calculation flow chart of FIG. 3 described later, and the result is displayed on the CRT 513 and printed on the printer 514. .

Next, for reference, a method of calculating a fault point and a fault point resistance when a system fault occurs will be described. First,
A control condition matrix is formed based on the voltage and current signals at each terminal. FIG. 5 shows each phase of the three-phase AC parallel two-line power transmission line shown in FIG.

In FIG. 5, the transmission line No. 1 line 1L is shown as phase Nos. 1, 2, 3 and the transmission line No. 2L is shown as phases No. 4, 5, 6. That is, the voltage signals V ₁ , V ₂ ... V _{12 of} the S and R terminals and the current signals I ₁ , I _2, ... I ₁₂ are shown by subscripts so as to correspond to the phase order.
k is the distance to the accident point, the line length L from the S terminal
It is indicated by a ratio of ₀ being 1.

R ₁ , R ₂ ... R ₆ , R _E are the accident point resistances of each phase, and R _E is the common accident point resistance of the accident phase. E ₁ , E
₆ ... E _{12 also} relates to the voltage drop of the line of each phase not shown in the figure, and these voltage drops E ₁ , E ₆ ... E
₁₂ is

[0038]

[Equation 1] E ₁ = Z ₁₁ I ₁ + Z ₁₂ I ₂ + Z ₁₃ I ₃ + Z ₁₄ I ₄ + Z ₁₅ I ₅ + Z ₁₆ I ₆ E ₂ = Z ₂₁ I ₁ + Z ₂₂ I ₂ + Z ₂₃ I ₃ + Z ₂₄ I ₄ + Z ₂₅ I ₅ + Z ₂₆ I ₆ E ₆ = Z ₆₁ I ₁ + Z ₆₂ I ₂ + Z ₆₃ I ₃ + Z ₆₄ I ₄ + Z ₆₅ I ₅ + Z ₆₆ I ₆ (1) E ₇ = Z ₁₁ I ₇ + Z ₁₂ I ₈ + Z ₁₃ I ₉ + Z ₁₄ I ₁₀ + Z ₁₅ I ₁₁ + Z ₁₆ I ₁₂ E ₁₂ = Z ₆₁ I ₇ + Z ₆₂ I ₈ + Z ₆₃ I ₉ + Z ₆₄ I ₁₀ + Z ₆₅ I ₁₁ + Z ₆₆ I ₁₂

However, Z ₁₁ , Z _12, ... Z ₆₆ are impedances per 1 km between the respective phases of the transmission line, and are composed of impedance matrices which are symmetrical between the respective phases. In order to simplify the explanation, the uniform distribution constant is used in the span length L ₀ (km). In this equation (1), the voltage signal V
₁ , V ₂ ... V _12, current signals I ₁ , I ₂ ... I ₁₂ , impedances Z ₁₁ , Z ₁₂ ... Z ₆₆ are all complex numbers,
E ₁ , E ₂ ... E ₁₂ are also complex numbers.

[0040] In addition, current I _E flowing through the fault point resistance R _E is,

[0041]

[Equation 2] I _E = I ₁ + I ₂ ... + I ₁₂ (2)

In FIG. 5, the voltage equation of each terminal and each phase

[0043]

V ₁ = kL ₀ E ₁ + R ₁ (I ₁ + I ₇ ) + R _E I _E V ₂ = kL ₀ E ₂ + R ₂ (I ₂ + I ₈ ) + R _E I _E V ₃ = kL ₀ E ₃ + R ₃ (I ₃ + I ₉ ) + R _E I _E V ₄ = kL ₀ E ₄ + R ₄ (I ₄ + I ₁₀ ) + R _E I _E V ₅ = kL ₀ E ₅ + R ₅ (I ₅ + I ₁₁ ) + R _E I _E V _{6 = kL 0 E 6 + R} 6 (I 6 + I 12) + R E I E ... (3) V 7 = (1-k) L 0 E 7 + R 1 (I 1 + I 7) + R E I E V 8 = ( 1-k) L ₀ E ₈ + R ₂ (I ₂ + I ₈ ) + R _E I _E V ₉ = (1-k) L ₀ E ₉ + R ₃ (I ₃ + I ₉ ) + R _E I _E V ₁₀ = (1- k) L ₀ E ₁₀ + R ₄ (I ₄ + I ₁₀ ) + R _E I _E V ₁₁ = (1-k) L ₀ E ₁₁ + R ₅ (I ₅ + I ₁₁ ) + R _E I _E V ₁₂ = (1-k) L ₀ E ₁₂ + R ₆ (I ₆ + I ₁₂ ) + R _{E IE} holds.

This equation (3) includes complex numbers, but the unknowns are k indicating the position of the fault point, the fault point resistances R ₁ , R ₂ ... R ₆ , R _E of each phase, and the unknown number is 8 because there is,
The position k of the accident point and the accident point resistances R ₁ , R ₂ ... R ₆ , R _E necessary for identifying the accident aspect can also be obtained by directly solving the equation (3). Since each equation of the equation (3) uses the measured values of the voltage and current signals, it is conceivable that the measurement error may be included.

The complex equation (3) for a certain one-time section is shown by simultaneous equations in which the real part and the imaginary part are separated.

[0046]

## EQU4 ## V _1r = kL ₀ E _1r + R ₁ (I ₁ + I ₇ ) _r + _{RE E IE} + X _1r V _1I = kL ₀ E _1I + R ₁ (I ₁ + I ₇ ) _I + _{RE E IE} + X _1I V _2r = KL ₀ E _2r + R ₂ (I ₂ + I ₈ ) _r + _{RE E E} + X _2r (4) V _12I = (1-k) L ₀ E _12I + R ₆ (I ₆ + I ₁₂ ) _I R _{E IE} X _{Like 12I} , 24 simultaneous equations can be set. However, X _1r , X _1I , ..., X _12I are error terms of each equation. Further transforming equation (4),

[0047]

[Equation 5] V _1r = kL0E _1r + R ₁ (I ₁ + I ₇ ) _r + U _1r + RE _{E Er} + U _Er + X _1r V _1I = kL0E _1I + R ₁ (I ₁ + I ₇ ) _I + U _1I + R _E I _EI + U _EI + X _1I V _2r = kL0E _2r + R ₂ (I ₂ + I ₈ ) _r + U _2r + RE _{E Er} + U _Er + X _2r (5) V _12r −L 0E _12r = −kE _12r + R ₆ (I ₆ + I ₁₂ ) _r + U _6r + put and _{R E I Er + U Er +} X 12r X 12I -L0E 12I = -kE 12I + R 6 (I 6 + I 12) I + U 6I + R E I EI + U EI + X 12I. In equation (5), U _1r , U _1I , U _2r ...
U _6I , U _ER , and U _EI are correction terms, the accident phase uses the resistance R term, and the sound phase uses the correction term U.

FIG. 2 is a processing flow chart of the present invention, and the contents of arithmetic processing will be described in detail based on this drawing. 2 is a PC
It is an internal processing flowchart of M relay (120, 130 of FIG. 1). As described above, the series of processes shown in this figure is endlessly repeated by the sampling signal generated at every 30 electrical degrees, regardless of whether or not there is a system fault.

First, in step 50, the presence / absence of a sampling signal for starting the following processing is determined. In step 51, the system voltage and current of its own terminal are A / D exchanged, the digital amount is taken in, and the device information is obtained. (CB state etc.) is taken in. Step 52 is a receiving process for fetching the current of the other terminal and the device information (CB status etc.) data to be used for the relay calculation. The current data of both terminals sampled at the same time and the voltage of the own terminal. The data is stored in the memory of step 53.

Using this stored data, step 5
Perform relay calculation in 4 to determine the occurrence of an internal accident due to a short circuit or ground fault in the system. If there is no internal accident as a result of the calculation, the relay does not operate and the process returns to step 70. In step 70, it is determined whether or not the data transfer flag is present. If yes, go to step 59. If no, go back to step 71.

In step 71, the storage address of the data used for the relay calculation is incremented by +1 so that the data can be sequentially stored in time series, step 72.
Then processing to store the limited memory endlessly,
Step 73 is a process for updating when the memory storage address reaches the final address.

If there is no internal accident, the processes from step 50 to step 55 are performed, and the process returns to the beginning via step 70. If an internal accident occurs and the relay operates,
The data transfer flag is set in step 56, and the current and voltage data stored in the memory is frozen in step 57. However, the memory is frozen by the memory 125 of FIG.
The storage address of the memory 123 used for the relay calculation is updated every 30 electrical degrees.

Step 58 is a circuit breaker trip command processing for protecting the system based on the internal accident determination result by the relay operation. Steps 59 and 60 are the transmission line 331 of FIG.
A process of confirming whether data can be transmitted by both parties via 334. Step 61 is a trouble during data transfer.
When the data is interrupted on the way, a retransmission request flag is determined from an arithmetic unit (hereinafter abbreviated as the central arithmetic unit) 510 installed elsewhere in FIG.

Step 62 is a frozen accident current,
An address is added from the voltage data storage memory and data of a predetermined word is transmitted to the arithmetic unit 510 installed elsewhere through the transmission lines 331 and 334 of FIG. Step 6
3 is a transmission end determination process for all data, and step 64 is a reception end response process from the arithmetic unit 510 in the center of FIG.
If the reception has been completed, the data transfer flag is reset in step 65 and the process returns to the beginning.

Step 66 is the central processing unit 510 of FIG.
Is a process for determining the presence or absence of a data resend request issued when there is a data reception failure. If there is a data resend request, the resend flag is set in step 67 and the process returns to the beginning process.

In step 68, regardless of the end of the transmission of all data, since steps 64 and 66 are negative, the data cannot be sent to the central processing unit 510 in FIG. The process, step 69, is a process of resetting the transfer flag and the retransmission flag, ending the transfer process, and returning to the leading process.

Next, the contents of the data reception processing of the central processing unit 510 of FIG. 1 will be described with reference to the data reception processing flow of FIG. The transmission device 332 on the S terminal side, the transmission device 335 on the R terminal side, and the transmission devices 333 and 336 installed in the central processing unit 510 in FIG. 1 are transmission lines 331 and 334, respectively.
Data is always transmitted and received through the network.

Step 80 in this figure is a process for confirming the presence / absence of a transmission request from the S terminal. If there is a transmission request, the process proceeds to step 81 to perform data reception processing on the S terminal side, and no transmission request. In the case of, the process proceeds to step 89. Step 89 is a process for confirming the presence or absence of a transmission request from the R terminal, and if there is a transmission request, step 90
Then, the process proceeds to step R and the data reception process on the R terminal side is performed.

If there is no transmission request, the process returns to the beginning process and waits for a data transmission request in the initial state. In step 81, data for a predetermined word of data on the S terminal side is received, and received data is successively accumulated. Step 82 is a process of determining whether or not reception of all data on the S terminal side has been completed. When reception of all data has been completed, an S terminal data reception completion notification is issued in step 83, and the transmission device 333, transmission path 331, The S terminal side is notified that the data on the S terminal side has been received via the transmission device 332 on the S terminal side.

On the S terminal side, the determination is made in step 64 of FIG. 2, and the transmission processing from the S terminal is ended. Step 8
If the data is being received in the process of 2, the process of error detection of the received data of a predetermined word is performed in step 84. If there is no error, the process returns to the top processing. If there is an error, the retransmission flag is set in step 85. Step 86 is a process for setting the number of retransmissions,
In step 87, the number of retransmissions determination processing is performed, and if the same data is received N times and the error continues, in step 88 an alarm of poor data reception is issued and the processing returns to the top processing.

When the data receiving process on the S terminal side is completed,
Next, the data reception process on the R terminal side is performed in steps 90 to 97 in the same manner as the S terminal. When the data reception on the S terminal side and the R terminal side is completed, as shown in FIG.
The CPU 511 calculates the accident point and the accident point resistance according to the calculation flow chart of FIG.

Here, since the CPU 511 can perform the calculation when the data on the S terminal side and the R terminal side is received for the electrical angle of 30 degrees, the steps from the step 40 of the calculation flow of FIG. It is also possible to increase the processing speed by performing the processing up to 46. If it is desired to know only the accident point for some purposes, the processing speed of the CRT 513 and the printer 514 in FIG. 1 can be made extremely high.

In this way, the PCM relay has the memory 1 shown in FIG.
25, 127 and transmission devices 332, 335 can be realized in hardware, and by adding the processes of steps 56 to 57 and 59 to 73 of the internal process flow diagram of FIG. Since it can be realized without impairing the function of, the equipment cost can be significantly reduced compared to the conventional technology.

The terminal 1 shown in FIG. 4 which is required in the prior art.
00 and 200 and the transmission line 310 can be shared with the PCM relays 120 and 130 and the transmission line 159 of FIG. 1, there is no need to install the device, and the equipment cost is greatly reduced and the installation space of the device in the substation is reduced. There is a great advantage that it is unnecessary.

[0065]

As described above, according to the present invention, the terminals at both ends of the power transmission line and the dedicated transmission line are unnecessary, and therefore the facility cost can be significantly reduced without impairing the function of the conventional PCM relay. It is also possible to obtain a fault point locating device for this type of power system that does not require a space for installing the device in a substation.

[Brief description of drawings]

FIG. 1 is a block diagram showing a failure point evaluation device for a power system according to the present invention.

FIG. 2 is an internal processing flow chart of the PCM protection relay device used in the failure point evaluation device of the power system of the present invention.

FIG. 3 is a data reception processing flow chart of the central processing unit used in the failure point evaluation device of the power system of the present invention.

FIG. 4 is a block diagram showing a conventional fault evaluation device for a power system.

FIG. 5 is an explanatory diagram of a calculation method using a two-terminal two-phase parallel two-line power transmission line.

FIG. 6 is a calculation flowchart.

FIG. 7 is a block diagram of a master station including a central unit and data collection of a conventional fault evaluation device for a power system.

[Explanation of symbols]

120 ... PCM carrier protection relay device, 125 ... memory, 332 ... transmission device, 510 ... central processing unit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sun Xiang Xiao 15-1 Ushijimacho, Toyama City, Toyama Prefecture Hokuriku Electric Power Company

Claims (7)

[Claims] 1. A fault point locating device for a power system, which is configured to perform a fault point locating operation by a computing device using sampling-synchronized voltage and current information of each terminal of the power system. Means for sampling the current information of each terminal together with the voltage information at the same time, and storing the voltage and current information in the memory in the PCM carrier protection relay arranged at each terminal of the A means for freezing the voltage and current information of a predetermined sampling section stored in the memory at times and means for transmitting the frozen data of the freezing means to the arithmetic unit are provided, and the arithmetic unit is provided with the PCM carrier protection relay. Provided is means for receiving data transmitted from the device, and means for locating an accident point by arithmetic processing based on data received by the receiving means. Fault point locating system of the power system, characterized in that. 2. A fault point locating device for a power system configured to perform fault point locating calculation by a computing device using voltage and current information synchronized with sampling of each terminal of the power system. Means for storing self-terminal voltage information and current information in a built-in memory in a PCM carrier protection relay device arranged at each terminal section of the device, and voltage and current information of a predetermined sampling section stored in the memory when an accident is detected. To freeze the data, means for transmitting frozen data to the PCM carrier protection relay device at the other end, means for receiving transmission data transmitted from the PCM carrier protection relay device at the other end, the freeze data and the Means for transmitting received data to the arithmetic device, and data transmitted from the PCM carrier protection relay device to the arithmetic device Means for receiving, fault point locating system of the power system, characterized in that a means for orientation the fault point by the original arithmetic processing the received data of the receiving means. 3. A fault point locating device for a power system, configured to perform fault point locating operation using sampling-synchronized voltage and current information of each terminal of the power system, wherein each terminal of the power system Each PCM located in the department
A means for mutually transmitting and receiving current data of each terminal and information of voltage data sampled at the same time, a means for storing the current information and voltage information in a built-in memory, and a carrier protection relay device, when an internal accident is detected. Means for freezing the current information, voltage information, and received current information and voltage information of the predetermined sampling section stored in the built-in memory, and the received freeze data and self-end freeze data of the freezing means And a means for locating an accident point by means of arithmetic processing, the fault point locating device for a power system. 4. A fault point locating method for a power system, wherein voltage and current information at each terminal of the power system is fetched, and a fault point is locating by an arithmetic process using this information. A method for locating a fault in a power system, characterized in that transmission of information for arithmetic processing is performed by a PCM carrier protection relay device arranged at each terminal of the power system. 5. A fault point locating method for a power system, wherein voltage and current information at each terminal of the power system is fetched and a fault point is located by arithmetic processing using this information. The internal PCM carrier protection relay device stores its own terminal voltage information and current information in the built-in memory, freezes the voltage and current information in the predetermined sampling section stored in the memory when an accident is detected, and uses this frozen data for other purposes. A method for locating a fault point in a power system, which has a function of transmitting / receiving between terminals and a function of transmitting this frozen data to a computing device. 6. A fault point locating method for a power system, wherein voltage and current information at each terminal of the power system is fetched and a fault point is located by arithmetic processing using this information. The existing PCM carrier protection relay device stores its own terminal voltage information and current information in the built-in memory, freezes the voltage and current information in the predetermined sampling section stored in the memory when an accident is detected, and saves this frozen data in another. A method for locating a fault point in a power system, which comprises transmitting / receiving between terminals and transmitting the frozen data to a computing device. 7. A fault point locating method for a power system, wherein voltage and current information at each terminal of the power system is fetched and a fault point is locating by a calculation process using this information. Each PCM carrier protection relay device arranged in the terminal section stores its own terminal voltage information and current information in the built-in memory, and also the voltage and current information of the predetermined sampling section stored in the memory when an internal accident is detected. So that the frozen data is transmitted and received between the PCM carrier protection relay devices, and the frozen data received from the other end PCM carrier protection relay device and the own terminal freezing data are transmitted to the fault point location calculation device. A method for locating a fault point in a power system, which is characterized by the above.