JPH0923567A - Protective relay and its response analyzer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lessen the CPU's burden of calculation and speed up the operation of an overcurrent relay by preventing the operation and output of a protective relay device for protecting a bus by the operation and output of the overcurrent relay that calculates the ocvercurrent using a current data of a second memory circuit. SOLUTION: In the case that a CT ratio of a line 1L is small and CT could be saturated when an accident occurs outside, the data address of the assigned line is set by means of a setting circuit 21A by conducting the line assignment of 1L and a CPU saves the current data of the assigned line 1L in an assigned memory 22A from a memory of a memory circuit 12. The data saved in the memory 22A is fetched into an overcurrent relay 23A in the after stage and then overcurrent is calculated. Overcurrent relays 23B, 23C for which no line assignment has been made make no calculations including the fetch of data to assigned memories 22B, 22C. By this method, relays' burden of calculation is lessened and a high speed operation of the relays is possible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital protective relay device for performing a protection calculation by inputting electric quantities of multiple lines, and a response analysis device for analyzing the response of the device.

[0002]

2. Description of the Related Art In a busbar protection relay device configured to take in the electric quantities of multiple lines and perform a protection calculation, an overcurrent relay is provided to prevent the busbar protection relay (differential relay) from operating when an external accident CT is saturated. , In some cases, the busbar protection relay device may be prevented from malfunctioning in the event of an external accident. This overcurrent relay is provided for every line, and the CT ratio is small, and it is limited to the line (for example, load line) where CT saturation is expected at the time of an external accident, and the function is used only for the necessary line by the switch etc. In addition, any bus line configuration can be supported.

An example of a conventional busbar protection relay device is shown in FIG.
This will be described with reference to FIG. FIG. 5 shows a digital busbar protective relay device, where 1 is a busbar, 1L, 2L, and nL are lines connected to the busbar (3L to (n-1) L are not shown in the drawing),
2A, 2B, 2n are circuit breakers, 3A, 3B, 3n are instrument current transformers (CT), 10 is an input converter for converting the current introduced from the CT secondary circuit, and 11 is an analog quantity and a digital quantity. Analog to digital (AD)
A converter, 12 is a memory circuit for storing the current amount (digital amount) of each line, 13A, 13B, 13n are overcurrent relays for performing digital calculation using the current amount saved in the memory circuit 12, 14A , 14B and 14n are overcurrent relay output use / non-use selection switches, 15A, 15B and 15n are AND logics, 16 is OR logic, and 17 is a bus bar protection relay operation blocking output.

In FIG. 5, the current of each line is taken into the input converter 10 via the current transformers 3A, 3B, 3n for measuring instruments, and is insulated from the outside and the level is converted, and the latter stage analog / digital (AD) is used. ) Input to the converter 11. AD
The data converted into the digital value by the converter is further stored in the memory circuit in the subsequent stage, and the overcurrent relays 13A and 13A are
It is used as the input amount of B and 13n, and the overcurrent relay calculation is performed. The overcurrent relay output is configured to be used or not for busbar protection relay operation inhibition by AND logic with the "overcurrent relay use / non-use" selection switches 14A, 14B, 14n. That is, for example, since the line 1L is a load line, the CT ratio is small, and the CT ratio is small when an external accident occurs.
Switch 14 is determined to be saturated, switch 14
By A, overcurrent relay output is enabled only for line 1L,
The busbar protection relay operation blocking output 17 prevents malfunction of the busbar protection relay device.

[0005]

As described above, in the conventional CT saturation countermeasure of the busbar protection relay device, an overcurrent relay is provided for all lines (30 lines × 3 phases for a normal-scale substation). Since it is mounted, one CPU has too large a calculation load, so that it is necessary to add CPU hardware. Or 1
Since calculation of all lines is not completed during the sampling period, it is necessary to perform time division processing. Furthermore, the time division processing impairs the high speed of the overcurrent relay, and cannot be applied to prevent the operation of the busbar protection relay that requires high speed operation.

Therefore, an object of the present invention is to provide an overcurrent relay only for a necessary line without providing an overcurrent relay for all lines, thereby reducing the calculation load on the CPU and increasing the operating time of the overcurrent relay. The purpose is to enable application to protection relay devices (bus bar protection, circuit breaker non-operation protection) that require high-speed operation.

Further, in the protective relay device which takes in the electric quantities of other lines and performs digital calculation, the electric quantity data of all the lines are not saved, but the electric quantity data of only the cutoff line is saved. Detailed data by acquisition of each sampling data and analysis data with sufficient time width to endure the analysis can be obtained.
It is possible to reduce the calculation load on the PU, and if the number of disconnection lines exceeds a certain value, it is judged as a bus accident and the electric relay is activated to lock the electric quantity collection and prevent the calculation time from being exceeded. It is to provide an analysis device.

Further, in the protective relay device which takes in the electric quantities of the other lines and performs the digital calculation, the electric quantity data of all the lines is not saved, but the electric quantity data of only the cutoff line is saved. Detailed data by acquisition of each sampling data and analysis data with sufficient time width to endure the analysis can be obtained.
The calculation load on the PU can be reduced, and if the number of disconnection lines exceeds a certain value, it is judged as a bus fault and the amount of electricity is changed to time-division processing, making it possible to collect data on all lines. It is an object of the present invention to provide a response analysis device for a protective relay device that does not exceed time.

[0009]

SUMMARY OF THE INVENTION A protective relay device for protecting a bus of the present invention takes in an amount of current from a plurality of lines linked to a bus via a current transformer for an instrument, and measures the amount of current in the plurality of lines. Which determines the relay operation based on the difference between
The first memory circuit that stores the current amount data captured from multiple lines separately for each line and the protection target range of the protective relay device for protecting the bus concerned. A settling circuit for designating a line (a line to which an overcurrent relay needs to be applied), a second memory circuit for taking in and storing current amount data of the line designated by the settling circuit from the first memory circuit, and An overcurrent relay that performs an overcurrent calculation using the current amount data of the second memory circuit and a blocking circuit that blocks the operation output of the protective relay device for protecting the bus by the operation output of the overcurrent relay are provided. .

Further, the protective relay device for protecting the circuit breaker from malfunctioning according to the present invention includes a first memory circuit for separately storing current amount data taken from a plurality of lines for each line and a plurality of lines. A circuit breaker failure detection circuit that detects circuit breaker failure by the circuit breaker command to each circuit breaker and the circuit breaker closing signal continuing for a predetermined time, and circuit breaker for each circuit breaker on multiple lines A line determination circuit for determining a circuit breaker non-operation line from the output of the non-operation detection circuit, and a current amount data of the circuit breaker non-operation line determined by the line determination circuit is fetched from the first memory circuit and stored. A second memory circuit, an overcurrent relay that performs an overcurrent calculation using current amount data of the second memory circuit, and an output circuit that outputs an operation output of the overcurrent relay.

Further, the response analysis device of the protective relay device according to the present invention includes a first memory circuit for separately storing the current amount data fetched from a plurality of lines for each line and a circuit breaker for the plurality of lines. A cutoff line detection circuit that detects a line to which a cutoff command is output from a cutoff command to each circuit breaker, and current amount data of the cutoff line detected by the cutoff line detection circuit is fetched from the first memory circuit and stored. A second memory circuit and a control circuit that blocks storage in the second memory circuit when the cutoff line detection circuit detects a predetermined number or more of cutoff lines.

Further, in the response analysis device of the protective relay device according to the present invention, instead of the control circuit, when the cutoff line detection circuit detects a predetermined number or more of cutoff lines, the memory is stored in the second memory circuit. A control circuit for time-division processing is provided.

[0013]

The present invention has the following effects by taking the above measures. According to the present invention corresponding to claim 1, a line having a possibility of CT saturation is set by settling, and an overcurrent relay for CT saturation detection is provided only in the set line. The calculation load is reduced, high-speed overcurrent relay calculation is possible, and the operation of the busbar protection relay can be reliably blocked by the overcurrent relay during CT saturation in an external accident without delaying the operation time of the busbar protection relay. .

According to the present invention corresponding to claim 2, after the circuit breaker non-operation line is determined based on the circuit breaker command from each circuit protection relay device and the bus bar protection relay device and the circuit breaker auxiliary contact condition, the circuit concerned. By enabling the overcurrent relay of
Compared to the method of providing overcurrent relays on all lines, the calculation load can be significantly reduced and the hardware configuration can be simplified.

According to the present invention, which corresponds to claim 3, only the electric quantity data at the time of the accident of the cutoff line is saved by the cutoff command from each line protection relay device and bus protection relay device. The calculation load is reduced compared to the data collection method for all lines, and the reduced load can be used for each data sampling process, enabling fine data recording and long-term data recording depending on the memory capacity. Become. Further, in the event of a bus accident, by locking the data save process, it is possible to prevent the previous data record from being inadvertently overwritten.

According to the present invention according to claim 4, only the electric quantity data at the time of the accident of the cutoff line is saved by the cutoff command from each line protection relay device and the busbar protection relay device. The calculation load is reduced compared to the data collection method for all lines, and the reduced load can be used for each data sampling process, enabling fine data recording and long-term data recording depending on the memory capacity. Become. Furthermore, in the event of a bus accident, data saving can be performed in a time-division manner, so that it is possible to record the amount of electricity at the time of an accident in all lines without omission.

[0017]

Embodiments of the protective relay device of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of the present invention. The same parts as those in FIG. 5 described above are designated by the same reference numerals, and the description thereof will be omitted. Here, different parts will be described.

In FIG. 1, 21A, 21B and 21C are settling circuits for setting the settling conditions for designating the lines requiring CT saturation countermeasures, and 22A, 22B and 22C are 21A and 21C.
Designated memories for saving current data of the lines designated by B and 21C, and 23A, 23B and 23C are overcurrent relays (overcurrent relay elements). The current of each line is taken into the input converter 10 via the instrument current transformers 3A, 3B, 3n, performs insulation and level conversion from the outside, and is input to the analog / digital (AD) converter 11 in the subsequent stage. To be done. now,
If the CT ratio of the line 1L is small and there is a risk of CT saturation in the event of an external accident, the 1L line is designated to set the designated line data save address by the settling circuit 21A, and the CPU sets the designated line 1L in the designated memory 22A. Save the current data of 12 from 12 memories. The data saved in the memory 22A is taken into the overcurrent relay 23A in the subsequent stage and the overcurrent calculation is performed. 23B, 23 without line designation
The overcurrent relay of C does not perform the arithmetic processing including the data acquisition into the designated memories 22B and 22C. In the embodiment of FIG. 1, the line designation is limited to 3 lines, and the designation memories 22A to 22
C, 3 sets of overcurrent relays 23A-23C are provided, but CP
It is arbitrarily determined in consideration of the arithmetic processing capacity of U, system conditions, and the like.

As described above, according to the present embodiment, the lines for which the CT saturation countermeasure is required are designated in advance by settling, and only the overcurrent relay calculation of the designated lines is performed. Etc.), the overcurrent relay is mounted, and the relay calculation processing load is significantly reduced compared to the conventional method of performing relay calculation for all lines.
It is possible to provide an overcurrent relay capable of high-speed operation without the need for additional U or time-division processing for relay calculation.

As an application example, in the above embodiment,
A plurality of sets of designated memories and overcurrent relays are provided, and when the line designation is only 1L, the settling circuit 21B also saves 1L of current data in the designated memory 22B and causes the overcurrent relay 23B to also be operated. Further, the OR logic or AND logic of the outputs of the overcurrent relays 23A and 23B may be used as the operation blocking output of the bus protection relay to further improve the reliability.

Next, a second embodiment of the present invention will be described. FIG. 2 shows the structure of the apparatus according to the second embodiment. This embodiment is a circuit breaker malfunction protection relay for a line connected to a substation bus, and 31A, 31B, 31n are circuit breaker malfunction detection circuits (1L, 2L) provided corresponding to each line.
... Only 1L, 2L, and nL of nL lines are shown. ),
31U, 31V, 31W, and 31X indicate internal elements of the circuit breaker failure detection circuit. 31U is a circuit breaker auxiliary contact of the line, 31V is a circuit breaker command to the circuit breaker, and 31W is A.
ND logic, 31X is an on-delay timer for circuit breaker malfunction confirmation, 32 is a line determination circuit that detects a circuit in which circuit breaker malfunction is detected, and outputs a command to save the current data of the circuit to a designated memory in the subsequent stage, 33A , 33B is a memory for saving the current data of the line designated by the line determination circuit 32, 34B
A and 34B indicate overcurrent relays.

Now, let us consider a case where the circuit breaker 2A does not operate even though the line protection relay device for the 1L line has issued a breaking command. The conditions of the disconnection command 31U to the 1L line circuit breaker and the circuit breaker auxiliary contact 31V are established, the output of the AND logic 31W activates the on-delay timer 31X, and the line determination circuit 32 determines that the circuit breaker of the 1L line is not operating. , Memory 33
Control is performed so that the current data of the 1L line is saved in A, and the relay operation of only the overcurrent relay 34A in the subsequent stage is executed. Although not shown in the figure, this overcurrent relay output is ANDed with the circuit breaker malfunction detection circuit 31A output, and becomes an external output after performing a logical operation considering a sufficient cooperation time. The relevant circuit breaker is tripped and the accident is cleared. Normally, the circuit breaker malfunction does not occur rarely, and even if it occurs, it is rare that multiple circuit breakers malfunction at the same time. Then, it was explained using two circuits, but it is considered sufficient to prepare relays for several lines. As described above, according to this embodiment, since only the overcurrent relay calculation of the line in which the circuit breaker malfunction is detected is performed, compared with the conventional method in which the overcurrent relay is mounted on all the lines and the relay calculation is performed. As a result, the load of relay calculation processing is significantly reduced, and the device can be simplified.

Next, a third embodiment of the present invention will be described. FIG. 3 shows the configuration of the apparatus according to the third embodiment. This embodiment is a response analysis device mounted on a circuit breaker non-operation protection relay device of a line connected to a substation bus.
A, 41B and 41n are disconnection commands (1L, 2L ... 1L, 2 out of nL lines) to the circuit breakers provided corresponding to the respective lines.
Only L and nL are shown. ), 42 is a control circuit that detects the cutoff line and outputs a command to save the current data of the line to the designated memory in the subsequent stage, 42A and 42B indicate internal elements of the control circuit 42, and 42A is the cutoff line. A line detection circuit, 42B is a circuit for detecting interruption by a bus protection relay device, 43X is NOT logic, 43Y is AND logic, 44 is a memory for saving current data of the line designated by the control circuit 42, 44A, 44B, 44C shows current data of the line designated by the control circuit 42.

Now, let us consider a case where the line protection relay device for 1L and 2L lines issues an interruption command. The conditions of the interruption commands 41A and 41B to the circuit breakers of the 1L and 2L lines are satisfied, the interruption line is detected by the interruption circuit detection circuit 42A, and the control circuit 42
Shows the current data of the 1L and 2L lines respectively in the memory 44 44
Save to the address indicated by A and 44B. Next, in the case of the interruption due to the operation of the busbar protective relay device, the detection circuit 42B detects that the number of interruptions exceeds the preset number of lines, locks the save operation to the memory 44, and calculates. It is possible to prevent the CPU from being overloaded, such as the processing time being exceeded. That is, the output of the detection circuit 42B in FIG.
The X output becomes "0", the control output of the control circuit 42 is locked, and the current data saving operation to the memory 44 is not performed.

The above description is an example of data saving in the case of a two-line fault, but all current data of the fault-occurring line can be saved with the upper limit of the number of lines set in the detection circuit 42B. In addition, since the number of lines that can be saved is limited, special processing such as time division processing is unnecessary, each sampling processing can be performed, and detailed current data can be acquired and sufficient recording time can be secured. Although the embodiment is an example of the data save circuit of the response analysis device mounted on the circuit breaker non-operation protection relay device, the same description can be applied to the case where it is mounted on the busbar protection relay device or the like.

FIG. 4 shows the structure of an apparatus according to the fourth embodiment. This embodiment is a response analysis device mounted on a circuit breaker non-operation protection relay device of a line connected to a substation bus. The difference from FIG. 3 is that there is no 43X, 43Y logic circuit.

The response when the line protection relay device for the 1L and 2L lines issues a cutoff command is the same as that in the third embodiment, but in the case of a cutoff due to the operation of the busbar protection relay device, the detection circuit 42B is used. Detects that the number of cutoffs has exceeded the number of lines set in advance, the save operation processing to the memory 44 is time-division processing, and the CPU load overrun such as the calculation processing time overrun is prevented.

As described above, except for the operation of the busbar protective relay device, special processing such as time-division processing is unnecessary, each sampling processing can be performed, and detailed current data acquisition and sufficient recording time can be secured. You can On the other hand, even when the busbar protection relay device is operating, by performing the time-division processing, it is possible to perform the data save processing of all the corresponding lines as much as possible and easily perform the data analysis.

[0029]

As described above in detail, according to the present invention, the degree of freedom for settling change is left in all lines, and the overcurrent relay is applied only to necessary lines to prevent the busbar protection relay operation at CT saturation. As a result, it is possible to provide a busbar protection relay device that can reduce the calculation load on the CPU, speed up the operating time of the overcurrent relay, and simplify the device.

Further, according to the present invention, the overload relay operation is carried out only on the line in which the circuit breaker malfunction occurs without providing the overcurrent relay on all lines, thereby reducing the operation load on the CPU and simplifying the apparatus. It is possible to provide a circuit breaker non-operation protection relay device that can achieve the above.

Further, according to the present invention, instead of saving the electric quantity data of all the lines, the electric quantity data of only the cutoff line is limited to the electric quantity data save, and as a result, the detailed data by the acquisition of each sampling data, and Analysis data with sufficient time width for analysis can be obtained, and CP
It is possible to reduce the calculation load on U, and when the number of disconnection lines exceeds a certain value, it is judged as a bus accident and the electric relay is activated to lock the electric quantity collection and prevent the calculation time from being exceeded. An analysis device can be provided.

Further, according to the present invention, instead of saving the electric quantity data of all the lines, the electric quantity data of only the cutoff line is limited and saved. As a result, detailed data obtained by acquiring each sampling data, and Analysis data with sufficient time width for analysis can be obtained, and CP
It becomes possible to reduce the calculation load on U, and when the number of cutoff lines exceeds a certain value, it is judged as a bus accident and the electricity quantity collection is changed to time-division processing, making it possible to collect data for all lines. It is possible to provide a response analysis device for a protective relay device that does not exceed time.

[Brief description of drawings]

FIG. 1 is a busbar protective relay device according to a first embodiment of the present invention.

FIG. 2 is a circuit breaker inoperative protection relay device according to a second embodiment of the present invention.

FIG. 3 is a response analysis device incorporated in a circuit breaker non-operation protection relay device according to a third embodiment of the present invention.

FIG. 4 is a response analysis device incorporated in a circuit breaker non-operation protection relay device according to a fourth embodiment of the present invention.

FIG. 5: Busbar protection relay device with CT saturation measures implemented.

[Explanation of symbols]

1 ... Bus bar, 1L, nL ... Line, 2A-2n ... Circuit breaker, 3
A to 3n ... Current transformer (CT) for instrument, 10 ... Input converter, 11
... Analog / digital converter (A / D), 12 ... Memory circuit, 21A-21C ... Settling circuit, 22A-22C, 33A, 33B,
44 ... Specified memory circuit, 23A-23C, 34A, 34B ... Overcurrent relay, 31A-31C ... Circuit breaker failure detection circuit, 32 ... Line determination circuit, 41A-41n ... Break command, 42A ... Break line detection circuit.

Claims (4)

[Claims] 1. A protective relay for protecting a bus, which takes in an amount of current from a plurality of lines linked to a bus through a current transformer for an instrument, and makes a relay operation determination based on a difference in the amount of current of the plurality of lines. In the device, a first memory circuit for separately storing the current amount data fetched from the plurality of lines for each line and a protection target range of the protection relay device for protecting the busbar A settling circuit for designating a line predicted to be saturated, a second memory circuit for fetching and storing current amount data of the line designated by the settling circuit from the first memory circuit, and the second memory circuit An overcurrent relay that performs overcurrent calculation using the current amount data of
A protection relay device for protecting the busbar, comprising: a blocking circuit that blocks the operation output of the protection relay device for protecting the busbar by the operation output of the overcurrent relay. 2. A first memory circuit for separately storing current amount data fetched from a plurality of lines for each line, a break command for each breaker of the breakers of the plurality of lines, and a breaker of the breaker. A circuit breaker non-operation detection circuit that detects circuit breaker non-operation by the closing signal continuing for a predetermined time, and a circuit that does not operate circuit breaker from the output of the circuit breaker non-operation detection circuit for each circuit breaker of the plurality of circuits. A line determination circuit for determining
A second memory circuit that takes in the current amount data of the circuit breaker inoperative circuit determined by the line determination circuit from the first memory circuit and stores it, and the current amount data of the second memory circuit An overcurrent relay that calculates current,
A protection relay device for circuit breaker non-operation protection, comprising: an output circuit that outputs an operation output of the overcurrent relay. 3. A first memory circuit for separately storing current amount data fetched from a plurality of lines for each line, and a breaking command output from a breaking command to each breaker of the breakers of the plurality of lines. A cutoff line detection circuit for detecting the broken line,
A second memory circuit for fetching and storing the current amount data of the break line detected by the break line detecting circuit from the first memory circuit, and when the break line detecting circuit detects a break line of a predetermined number or more. A response analysis device for a protective relay device, comprising: a control circuit that blocks storage in the second memory circuit. 4. The control according to claim 3, wherein instead of the control circuit, when the cutoff line detection circuit detects a predetermined number or more of cutoff lines, the storage in the second memory circuit is time-division processing. A response analysis device for a protective relay device, comprising: a circuit.