JPH07336874A - Current differential protective relay device - Google Patents

Abstract

PURPOSE:To detect the difference of the state of the operation of an actual system and the recognition of each terminal at an early stage by a method wherein opposite terminal quiescence detected by its own terminal and the opposite terminal quiescence of another terminal by another terminal to the terminal are detected, the results are received by its own terminal, the mismatch of both quiescence is compared and an alarm is given when the the mismatch is conformed to a specified alarm logic. CONSTITUTION:An opposite-terminal quiescence detector 11 receives control data from a plurality of opposite terminals and detects the state of quiescence or operation of each opposite terminal, and an opposite-terminal quiescence-signal generating circuit 12 generates signals for transmitting the results of detection by the opposite-terminal quiescence detector 11 over each different opposite terminal. The quiescence-condition alarm circuit 18 receives a quiescence detecting signal displaying the quiescence detection of another terminal transmitted from the opposite side and compares the quiescence detecting signal with an opposite-terminal quiescence signal detected by a corresponding opposite-terminal quiescence detector 21, and outputs the result. Accordingly, the difference of the state of the operation of an actual system and the recognition of each terminal can be detected at an early stage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a current differential protection relay device, which is used for protecting a power system having two terminals or more, and which takes into consideration the control of a quiescent end or an operating end.

[0002]

2. Description of the Related Art The configuration of a conventional current differential protection relay device and a system for controlling a quiescent end will be described with reference to FIG. Electric power stations (e.g., substations, switching stations, etc.) of the electric power system are interconnected by a power transmission line 1 via a bus bar 4, a circuit breaker 2, and a disconnector 3 of the respective terminals. A current transformer 5 is provided on the control device side of the bus bar 4 to measure the current value of the power transmission line 1 at its own terminal. From the current transformer 5 of the electric station A, the secondary side current i proportional to the current I _A flowing through the transmission line 1
_A is input to the input converter 6, converted into a signal level suitable for the circuit in the subsequent stage, converted into a digital signal by the A / D conversion circuit 7, and relayed through the transmission delay compensation circuit T _d 8. Input to the part 17.

Similarly, the pallet conditions for the circuit breaker at the electric station A
2b and disconnecting switch pallet condition 3b opening and closing information, self-end CB,
It is input to the LS condition signal generation circuit 9. So A / D
Output i _A1 of conversion circuit 7 and self-end CB, LS condition generation circuit 9
Outputs CB and LS-A are introduced into the communication device 10 at the self-end,
It is transmitted to the communication device 10 of the electric station B via the communication line 20.

The electric station B is also provided with a device having the same function as the electric station A, and the output i _{B1 of} the A / D conversion circuit 7 and the self-terminal C from the communication device 10 of the electric station B through the communication line 20.
The outputs CB and LS-B of the B and LS condition signal generating circuit 9 are transmitted to the communication device 10 of the electric station A. Communication device of electric station A
The signal of the electric station B received at 10 is introduced to the error detection circuit 14, and transmission error detection such as CRC cyclic code check and fixed bit check is performed. If a code error is detected, a relay output lock signal is generated. This will activate the circuit 15.

The output of the relay output lock signal generating circuit 15 is introduced to the relay determining section 17 to control the relay output to the lock side. Further, the output of the error detection circuit 14 is also introduced to the other end pause detection circuit 11 and controls so as to stop the pause end detection processing (hold the previous value of the pause end detection output). Among the received signals from the electric station B, the CB and LS-B signals are introduced into the other end pause detection circuit 11 and the logic is used to determine that the terminal is inactive due to the opening of the breaker or disconnector. When the circuit operates and the logic of the other party sleep is established, the other party sleep signal generating circuit 12 is started, the output of which is introduced into the other party current zero control circuit 13 and the reception signal i _B1 from the electric station B is made zero. The signal i _B1 obtained as a result is introduced to the relay determination unit 17.

Further, the other end pause signal output is also introduced to the relay output lock signal generation circuit 15 and also serves to prevent unnecessary output lock control from being carried out. On the other hand, the received signal from the electric station C is processed in the same manner as the received signal from the electric station B described above. However, for each circuit, the 10th series was used for reception from the B electric station, but the 20th series was used for reception from the C electric station, and the operation is the same as that of the 10th series circuit, so description is omitted. To do.

[0007] The difference of the current data i _C2 of the current data i _A2 and the mating end of Zidane the relay judgment section 17 of the A substation current data i _B2, remote end of (the substation B) (substation C) as input data The vector operation for obtaining the dynamic current is executed, and the location of the accident is determined from its magnitude. In principle, if a differential current exceeds a certain level, an internal accident (current transformer 5 at A substation, current transformer 5 at B substation, and current transformer 5 at C substation)
Therefore, the relay determining unit 17 generates the output T, and controls the circuit breaker 2 at each terminal to open.

[0008]

The above-mentioned conventional current differential protection relay device has some problems in the control method at the idle end. The contents will be described with reference to FIGS. 5, 6 and 7.
FIG. 6 shows a bus bar 4 of each of electric station A, electric station B, and electric station C.
Circuit breakers 2 (A), 2 (B),
The electric power system diagram of 3 terminals connected to the transmission line 1 via 2 (C) is shown. FIG. 7 shows a communication line installed for the power system shown in FIG. Since the problem to be solved here can be a particularly serious problem in a system with three or more terminals, an example of a three-terminal system will be described.

In a three-terminal power system, depending on the load condition of the system or various circumstances of each electric station, the breaker of one terminal may be opened and the remaining two terminals may be operated. In FIG. 6, for example, the case where the circuit breaker 2 (B) of the electric station B is opened and operated as a two-terminal power system of the electric station A and the electric station C is applicable. In such a case, the circuit breaker condition signal of the electric station B is CB, LS-, as described in FIG.
B signal is sent to substation A (and substation C),
The B terminal “pause” is confirmed by the other end pause detecting circuits 11 and 21 of each terminal, and the B terminal current is controlled, and predetermined measures are applied to the pause terminal to operate as a two-terminal system of A terminal-C terminal. Is possible.

From such a situation, it is assumed that the system operation plan is further changed and the operation is returned to the three-terminal system of A terminal-B terminal-C terminal. Naturally, the measure is to close the circuit breaker 2 (B) of the electric station B, but at this time, in FIG. 7, on the communication line BA (the communication line from the electric station B to the electric station A) (for example, × It is assumed that some line abnormality has occurred at the point indicated by the mark).
Normally, when a line abnormality occurs, the signal error detection circuit detects a communication abnormality at the terminal that receives a signal using the line as described with reference to FIG. 5, and control is performed so as to block the relay output.

However, this is not the case when the communication line from the idle end is abnormal as in the above example. As described in FIG. 5, since the function of locking the relay output by the error detection circuit is disabled by the output of the other party's pause signal, the abnormality of the communication line from the pause terminal appears on the surface as a result. There is no such thing. In the above example, by switching the circuit breaker from “open” to “closed” at the terminal B, the recognition of the terminal B on the opposite terminal side was changed from “resting end” to “operating end”. The breaker information of the terminal B is not transmitted to the terminal A due to the abnormality of the communication line BA, and as described above, the B terminal is "paused" at the A terminal.
In order to continue to recognize that the B-terminal breaker is "closed", the actual system is operating with 3 terminals,
The irregular operation is as follows where the recognition of each terminal is as follows.

☆ A terminal recognition: 2 terminal operation by A terminal-C terminal (B terminal is "pause"). ☆ B end (C end) recognition: 3 by A terminal-B terminal-C terminal
Terminal operation. In other words, despite the fact that the actual system is operated with 3 terminals, 2
Terminal A, which is mistaken for terminal operation, is in a serious state. For example, if a system accident occurs at point F (point outside bus 4 of terminal B) in FIG. Since the B terminal current is regarded as zero, a differential current that is not originally generated on the system side is apparently generated on the side of the current differential relay device, which is erroneously determined by the relay determination unit, resulting in the current differential. It is conceivable that an erroneous output may be generated from the relay device and the breaker may be tripped unnecessarily. The present invention has been made in order to solve the above problems, and to detect the difference in the operating state of the actual system and the recognition of each terminal at an early stage and output an alarm, or the difference in the recognition of each terminal to the actual system. It is an object of the present invention to provide a current differential protection relay device that can be matched to the operating state of.

[0013]

A current differential protection relay device according to claim 1 of the present invention is provided at each end of three or more terminals, converts the current value at each end into digital data, and outputs these currents. In a current differential protection relay device that performs protection calculation by combining data and control data indicating the control status of each terminal and mutually transmitting with each terminal, control data from multiple counterparts A partner end pause detecting means for receiving and detecting the rest or operating state of each partner end, and a partner end pause signal generating means for generating a signal for transmitting the detection result to each different partner end, And a warning means for receiving a pause detection signal indicating the detection of pause of another terminal transmitted from the other end, comparing it with the other end pause signal detected by the corresponding other end pause detecting means, and outputting the result. It was

According to a second aspect of the present invention, there is provided the current differential protection relay device according to the first aspect, when the other end pause detection signal indicating the pause detection of another terminal transmitted from the other end is received. When the pause detection signal detected by the corresponding other-end pause detection means holds the previous value, the held previous value is used as the other-end pause detection signal indicating the detection of the pause of the other terminal. Means for processing to match are provided.

A current differential protection relay device according to a third aspect of the present invention is provided at both ends of a two-terminal power transmission line, converts the current value at each end into digital data, and outputs these current data and each terminal. In a current differential protection relay device that performs a protective operation by transmitting control data together with control data indicating the control status to and from both terminals, the control data from the other end is received and the other end pauses. Alternatively, the other end pause detection means for detecting the operating state, the own end current detection means for detecting that the current of the own terminal is above or below a predetermined value, and the other end pause signal and the own end by the other end pause detection means. An alarm means for deriving an output from the current detected by the current detecting means is provided.

[0016]

In the current differential protection relay device according to claim 1 of the present invention, the breaker at the resting end is turned on under the condition that the communication line connecting the resting end and the working end is abnormal. In this case, the partner terminal pause detection signal detected at the own terminal at the operation terminal and the partner terminal pause detection signal at the terminal detected at another terminal are sent to the own terminal, and the result is received. The alarm output is generated when it is detected that the two are not the same.

In the current differential protection relay device according to the second aspect of the present invention, when the same operation is carried out under the same situation as described above, in the other end pause detection circuit due to the abnormality of the communication line at the own end. The other end pause detection result holds the previous value,
By receiving the release of the other party's pause signal from another party's terminal and releasing the other party's pause detection result that holds the previous value, the difference between the operating state of the actual system and the recognition of each terminal is eliminated, and ,
Since the other party's pause signal is released, an abnormality can be detected in the communication line and an alarm can be issued.

Since the current differential protection relay device according to claim 3 of the present invention is applied to the two-terminal system, when the self-end and the other-end breaker are turned on in the actual system, the power transmission line is not connected. Since a current flows, if the other end pause signal remains established when this current is detected at the self end, this can be alarmed.

[0019]

Embodiments will be described below with reference to the drawings. Figure 1
FIG. 3 is a configuration diagram of an embodiment of a current differential protection relay device according to claim 1 of the present invention, showing only an electric station A part. The same applies to the electric power stations B and C. In FIG. 1, the same parts as those in FIG. The feature of the configuration in FIG. 1 is that the output of the partner end pause signal generating circuit 12 is introduced into the communication device 10 so that it can be transmitted to another terminal different from the terminal, and similarly, the output of the partner end pause signal generating circuit 22. Is also introduced into the communication device 10 so that the same can be transmitted to another terminal different from the terminal.

Similarly, at the electric station B and the electric station C, since the corresponding counterpart end pause signals are transmitted to the electric station A, at the electric station A, when receiving from the electric station B, The other party pause receiving circuit 16 is provided in addition to the other party pause receiving circuit 26 for the reception from the electric station C. Further, the output of the other party's pause signal generating circuit 12 based on the received signal from the electric station B and the output of the other party's pause receiving circuit 26 which is the received signal from the electric station C are introduced to the pause condition warning circuit 18. The circuit is configured.

Similarly, the output of the other end pause signal generating circuit 22 based on the received signal from the electric station C and the output of the other end pause receiving circuit 16 which is the received signal from the electric station B are compared with the rest condition warning circuit. The circuit is configured to be introduced to 28. As a result, the signals relating to the suspension of the other end at the electric station A, the electric station B, and the electric station C are arranged as shown in FIG. It is obvious that each electric station obtains two types of signals regarding the suspension of the other end, that is, a signal directly detected by the other end and a signal that another terminal detects and transmits.

Next, the operation of the current differential protection relay device according to the first aspect will be described. Explaining the case of the suspension of the electric station B when there is no abnormality in the communication line, the electric station A detects the suspension of the electric station B by the received signal from the electric station B, and outputs the output of the partner end suspension signal generation circuit 12. It occurs and also sends it to the electrical station C. Similarly, the electric station C also detects the suspension of the electric station B by the received signal from the electric station B, generates the output of the partner end suspension signal generation circuit 22, and transmits the output to the electric station A as well. Therefore, at the electric station A, the other end pause receiver circuit 26 produces an output, so that both of the contents of the inputs of the pause detection alarm circuit 18 result in a pause at the electric station B, and no inconsistency occurs and no alarm is issued. Although the description of the electric station C is omitted, the operation is similar to that of the electric station A and no alarm is generated.

Next, when an abnormality occurs in the communication line BA in FIG. 2, the breaker of the electric station B is changed from "open" to "closed", that is, "stop" is changed to "operation". The case will be described. Here, since there is no abnormality in the communication lines between the electric station B and the electric station C and between the electric station C and the electric station A, the other party's pause signal generation circuit is restored at the electric station C. The output of the end pause receiver circuit 26 is restored. on the other hand,
Since the reception from the electric station B is abnormal at the electric station A, the CB and LS information of the electric station B cannot be received, and the other end pause detection circuit 11 stops the detection process. The end pause signal generating circuit 12 keeps producing an output. Therefore, the inputs of the rest condition warning circuit 18 are inconsistent with each other, and the malfunction can be warned to the outside.

At the electric station C, the other end pause signal generation circuit 12 at the electric station A keeps outputting, so that the other end pause receiving circuit for receiving the output also keeps producing output. As a result, even at the electric station C, the input of the rest condition alarm circuit is inconsistent. However, if this alarm is issued, the abnormality of the communication line for the electric station A is warned from two places, the electric station A and the electric station C. Is not preferable.
The prevention of this can be easily dealt with by the logical configuration of the pause condition alarm circuit. That is, the logical configuration of the circuit may be such that there is an input from the other end pause signal generating circuit and no input from the other end pause receiving circuit. According to this, at the electric station A, the above logic is established and the alarm can be issued without any trouble.
At the electric station C, the above logic is not established and no alarm is generated, but only at the electric station A.

According to the current differential protection relay device according to the first aspect of the present invention described above, in the system of three or more terminals, the other end pause detected at the own end and the other end of the other end of the corresponding terminal. It is configured to detect a terminal pause, receive this result at its own end, compare the two inconsistencies, and issue an alarm if the specified alarm logic is met. It is possible to detect the difference between the operating state of the actual system and the recognition of each terminal at an early stage.

FIG. 3 is a block diagram of an embodiment of a current differential protection relay device according to claim 2 of the present invention. In FIG.
The same parts as those in FIG. Figure 3
In the above, the first structural feature compared to FIG. 1 is that the rest condition alarm circuits 18 and 28 are deleted. or,
The second characteristic is that the output of the other-end pause receiving circuit 16 is introduced into the other-end pause signal generating circuit 22, and the output of the other-end pause receiving circuit 26 is introduced into the other-end pause signal generating circuit 12. To be there. Other configurations are the same as those in FIG.

Next, the operation of the current differential protection relay device according to the second aspect of the present invention will be described. The case of suspension of the electric station B when there is no abnormality in the communication line will be described. This is as will be apparent from the description of the embodiment of FIG. 1 described above. And the other end pause receiver circuit 26 also produces an output. In this case, no special control is performed. Next, the case where the breaker of the electric station B is changed from "open" to "closed", that is, "stop" is changed to "operation" when an abnormality occurs in the communication line BA in FIG. To do. Also in this case, as is apparent from the embodiment of FIG. 1, the pause edge detection circuit 11 stops the detection processing by the error detection circuit 14 because the communication line BA is abnormal (continues in the pause state), and the pause edge is detected. The previous value is retained as it is detected.

On the other hand, the output of the other end pause receiver circuit 26 is restored. This is because the communication line CA from the electric power station C to the electric power station A is sound, and the B terminal operation information detected at the C electric power station can be received at the A electric power station. At this time, the other-end pause signal generation circuit 12 is controlled so that the output of the other-end pause receiving circuit 26 is restored, so that the output is restored. Therefore, the output of the other party's pause signal disappears, and the electric station A also recognizes that it is operating as three terminals and detects an abnormality in the communication line BA as an error detection circuit.
When detected at 14, the relay output lock signal generation circuit 15 operates to lock the relay output.

This state is the same as when an error occurs in the communication line BA during normal operation of the three terminals and this is detected by the error detection circuit 14. As a matter of course, it goes without saying that a circuit (not shown) for warning the abnormality of the communication line performs a predetermined operation to warn the outside.

According to the above-mentioned current differential protection relay device of the present invention, when the result of the other end suspension of the self end is held at the previous value due to the abnormality of the communication line, another According to the received signal of the result of the other end pause of the terminal detected at the terminal, the other end pause detected at the own end is controlled to match, so the other end pause is correctly released, and the communication It is possible to detect a line abnormality in the same manner as in normal times and issue a predetermined alarm. Further, the lock of the relay output due to the abnormality of the communication line can be carried out similarly to the normal time.

FIG. 4 is a block diagram of an embodiment of a current differential protection relay device according to claim 3 of the present invention. 5 in FIG.
The same parts as those in FIG. Figure 4
In the above, the structural feature thereof is that a current relay 19 for inputting a current at its own end is provided, and its output is input to the rest condition alarm circuit 18 together with the output of the other end rest signal generation circuit 12. Also, while FIG. 5 is for a three-terminal system, FIG.
Deletes the part related to the C terminal for the two-terminal system.

Next, the operation of the current differential protection relay device according to the third aspect will be described. In a two-terminal system, when either the breaker or disconnector at the self-end or the other end is "open" (that is, when there is a "pause" terminal), no current flows in the transmission line and The current relay 19 having the terminal current as an input does not operate. On the other hand, at the terminal where "pause" is detected, the other end pause signal generation circuit 12 produces an output, and the input is given to the pause condition alarm circuit 18.

Since the output of the current relay 19 is also input to the rest condition alarm circuit 18 at the same time, if there is a partner end rest signal in the rest condition alarm circuit 18 and the operation of the current relay is the alarm logic, No alarm is issued.

As in the case of FIG. 1, when there is an abnormality in the line from the electric station B to the electric station A of the communication line 20 (for example, X mark in FIG. 4), the circuit breaker 2 of the electric station B is changed from "open" to "closed". It will be explained. In this case, it is similar to FIG.
Cannot receive that the circuit breaker at electric station B is "closed" due to an abnormality in the communication line. Therefore, the other end pause signal generation circuit 12 continues to detect the pause of the electric station B and continues to output the pause.

On the other hand, in the actual system, two-terminal operation is performed and current flows through the power transmission line 1, and the current relay 19 operates at its own end. Therefore, the pause condition alarm circuit 18 can issue an alarm when the other end pause signal is present and the logic of the current relay operation is established. Here, the current relay is used to detect the current at the self-end, but there is no problem in using a power relay in a system with no received current.

According to the current differential protection relay device according to claim 3 of the present invention, the current differential protection relay device is applied to a two-terminal system, and when two terminals are operated, a current exceeding a predetermined value can be detected at its own end. If the other end pause is detected at this time, there is an effect that an early warning can be given.

[0037]

As described above, according to the present invention, 1
From the terminal that operates the circuit breaker (the terminal that changes from "pause" to "operation") when changing the terminal from the resting end to the working end (changing the breaker from "open" to "closed") to another terminal Even if there is an abnormality in the communication line to which it is heading, the abnormality can be alarmed at the abnormal terminal, and the device will not be used for operation with the abnormality still present and without detecting it. A highly reliable current differential protection relay device can be provided.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a current differential protection relay device according to claim 1 of the present invention.

FIG. 2 is a diagram showing a detection state of a rest end at each end in a three-terminal system.

FIG. 3 is a diagram showing an embodiment of a current differential protection relay device according to claim 2 of the present invention.

FIG. 4 is a diagram showing an embodiment of a current differential protection relay device according to claim 3 of the present invention.

FIG. 5 is a diagram showing a conventional current differential protection relay device.

FIG. 6 is a three-terminal system diagram.

FIG. 7 is a communication circuit diagram of a three-terminal system.

[Explanation of symbols]

 1 Transmission line 2 Circuit breaker 3 Switch 4 Bus 5 Current transformer 6 Input converter 7 A / D converter 8 Transmission delay compensation circuit 9 CB, LS condition signal generation circuit 10 Communication device 11 Counter end pause detection circuit 12 Counter end Pause signal generation circuit 13 Counterpart current zero control circuit 14 Error detection circuit 15 Relay output lock signal generation circuit 16 Counterpart pause receiver circuit 17 Relay judgment unit 18 Pause condition warning circuit 19 Current relay 20 Communication line

Claims (3)

[Claims] 1. A terminal provided with three or more terminals, converting a current value at each terminal into digital data, and combining these current data and control data indicating a control state of each terminal with each terminal. In a current differential protection relay device that performs protection calculation by mutually transmitting with each other, the other end pause detection means for receiving control data from a plurality of other ends and detecting the rest or operating state of each other end. , A partner end pause signal generating means for generating a signal for transmitting the detection result to each different partner end, and a pause detection signal transmitted from the partner end indicating the pause detection of another terminal. Compared with the corresponding other end pause signal detected by the corresponding other end pause detection means,
A current differential protection relay device, comprising: an alarm means for outputting the result. 2. When receiving a partner end pause detection signal indicating a pause detection of another terminal transmitted from the partner end, the pause detection signal detected by the corresponding partner end pause detecting means holds the previous value. 2. The current according to claim 1, further comprising means for processing the held previous value so as to match the held previous value with the other end pause detection signal indicating the pause detection of the other terminal. Differential protection relay. 3. A two-terminal power transmission line is provided at both ends, the current value at each end is converted into digital data, and these current data and control data indicating the control state of each terminal are combined to make a connection between both terminals. In a current differential protection relay device that performs protection calculation by mutually transmitting between terminals, a partner terminal pause detecting means for receiving control data from the partner terminal and detecting a pause or operating state of the partner terminal, and its own terminal. Own current detection means for detecting that the current of the above is equal to or more than a predetermined value, and alarm means for deriving an output from the other end pause signal by the other end pause detection means and the detected current by the own end current detection means. A current differential protection relay device characterized by being provided with.