JP2637072B2 - Operation display circuit of protective relay - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation display circuit of a protective relay device that displays a relay that outputs a trip command to a circuit breaker.

[Conventional technology]

Generally, a protective relay has a plurality of relays that operate by detecting an element corresponding to a power system accident, and outputs a trip command to a circuit breaker when the operating conditions of these relays are satisfied. An operation display circuit is provided to indicate that the relay has operated in order to record the operation of the relay in the event of a system failure.

For example, an operation display circuit of a protection relay device having three relays (hereinafter referred to as relays) for detecting respective elements will be described with reference to the circuit diagram of FIG. An AND circuit (hereinafter referred to as an AND gate) that inputs the operation outputs of the respective relays 1, 2, and 3 and the trip command of the trip command circuit 4 that is output to the circuit breaker by the operation outputs of these relays 1, 2, and 3. 5) Operation display holding circuits 8, 9, 10 by the output of 5, 6, 7
Is set to light the indicators 11, 12, and 13. Once the operation display holding circuits 8, 9, and 10 are set, the display 1 is reset until reset by the output of the display return command circuit 14.
The lighting of 1,12,13 is held. This display return command circuit 14
Is generally operated by a push button switch provided in the protective relay device.

In the operation display circuit of the protective relay having the above-described configuration, an operation when the relay 1 operates due to a power system accident will be described. The trip command is output from the trip command circuit 4 by the operation output of the relay 1, and the AND gate 5 is established. The operation display holding circuit 8 is set by the output of the AND gate 5, and the display 11 is turned on. The operation display holding circuit 8 is reset by the display return instruction of the display return instruction circuit 14 by operating the push button switch of the protection relay device, the display is turned off, and the operation proceeds to the next accident.

[Problems to be solved by the invention]

As described above, in the conventional device, after the occurrence of the power system accident, the operation display state is held, the operation relay is checked and recorded, and then the operation display holding circuit 8 is reset by the display return command of the push button switch. Then, it is necessary to turn off the display 11 before starting the next operation. However, in unmanned electric power stations in recent years, it takes a lot of time from the occurrence of a power system accident to the time when a maintenance person returns to display. In this case, the circuit breaker is reclosed between the occurrence of the accident and the return of the display. This had led to confusion in release and investigation. In addition, the above-mentioned problem occurs even when the display is forgotten during maintenance, inspection, and testing.

Therefore, the present invention provides an operation display circuit of a protection relay device corresponding to a labor-saving and unmanned electric power station by updating the display contents due to the occurrence of an accident even if the display return operation is not performed.

[Means for solving the problem]

The present invention will be described with reference to the operation display circuit diagram of the protection relay device shown in FIG.

In an operation display circuit of a protective relay having an operation display holding circuit for holding an indication of which of the plurality of relays that operate upon detecting an accident in the power system and tripping the circuit breaker by the operation output, A first circuit that outputs for a predetermined time according to a trip command, a second circuit that outputs when the reclosing circuit of the circuit breaker is not in operation, and the operation display holding when the output of the first and second circuits is established. And a third holding circuit that outputs a holding release command to the circuit.

[Action]

Each time both the output of the first circuit, which is output within a predetermined time after the trip command is output to the circuit breaker, and the output of the second circuit, which is output when the reclosure circuit of the circuit breaker is not operating, the third circuit is established. Circuit updates the operation display contents of the operation display holding circuit.

〔Example〕

One embodiment of the present invention will be described with reference to the operation display circuit diagram of the protection relay device of FIG. 1 and a time chart showing the operation of the operation display circuit of FIG. In FIG. 1, the same devices and parts as those in FIG. 3 are denoted by the same reference numerals. For the sake of simplicity, relays that detect the corresponding elements
An operation display circuit of a protection relay having three relays will be described.

Indicators 11, 1 that display the operation of each relay 1, 2, 3
There are operation display holding circuits 8, 9, 10 that hold the lighting of 2,13,
Output when both the operation output of each of relays 1, 2, and 3 and the trip command from trip command circuit 4 are satisfied.
It is set by the outputs of the AND gates 5, 6, and 7. The display is kept on, and when reset, the display is turned off and turned off. These operation display holding circuits 8, 9, 10 are reset by a logical sum circuit having two inputs (hereinafter referred to as an OR gate).
Performed by 15 outputs. One input is a display return command of a display return command circuit 14 for operating a push button switch of the protection relay device as in the past, and the other input is a predetermined time output in response to a trip command from the trip command circuit 4. The output of the one-shot circuit 16 and the output of an AND gate 19 to which the output of an inverting circuit (hereinafter referred to as a NOT gate) 18 which outputs when the circuit breaker reclosing circuit 17 is not activated are input.

The operation of the operation display circuit having the above configuration will be described with reference to the time chart of FIG.

(I) When the relay 1 operates due to a power system accident.

A trip command is output from the trip command circuit 4 by the operation output of the relay 1, and the circuit breaker is tripped. At this time, since the reclosing circuit 17 has not been activated, the NOT gate 18 is outputting, and the one-shot circuit 16 for inputting the trip command outputs an output for a predetermined time, and the AND operation is performed.
The operation display holding circuits 8, 9, 10 are reset by the gate 19, and the indicators 11, 12, 13 are turned off. Thereafter, when the reclosing circuit 17 starts, the output of the NOT gate 18 disappears and the output of the AND gate 19 also disappears. At this time, since the operation output of the relay 1 and the trip command are established, the operation display holding circuit 8 is set by the AND gate 5, and the display 11 is turned on.

(II) When the relay 2 operates during the activation of the reclosing circuit 17.

The trip command is output from the trip command circuit 4, and the output is output for a predetermined time from the one-shot circuit 16, but the NOT gate 18 does not output while the reclosing circuit 17 is activated.
The ND gate 19 is not established, and the operation display holding circuits 8, 9, and 10 are not reset. At this time, since the operation output of the relay 2 and the trip command are established, the operation display holding circuit 9 is set by the AND gate 6, and the display 12 is turned on.

(III) After that, the indicators 11 and 12 are kept lit,
When the relay 3 operates in a state where the circuit breaker is turned on again by the reclosing circuit 17.

In this case, the reclosing circuit 17 is not activated and the NOT gate 18
The trip command is output from the trip command circuit 4 by the operation output of the relay 3 to trip the circuit breaker. At this time, the one-shot circuit 16 outputs an output for a predetermined time in response to the trip command, so that the AND gate 19 is established and the operation display holding circuits 8, 9, and 10 are reset. Therefore, all the indicators 11, 12, and 13 are turned off. Then, when the reclosing circuit 17 starts, the output of the NOT gate 18 disappears,
Gate 19 no longer holds. At this time, since the operation output of the relay 3 and the trip command are established, the operation display holding circuit 10 is set by the AND gate 7, and the display 13 is turned on.

As described above, the operations of the relays 1 and 2 during the period from the first trip command to the restart of the circuit breaker are regarded as the same accident, and the operation display of the relays 1 and 2 is maintained as the same accident. The operation of the relay 3 is an operation display circuit of the protection relay device for updating the content of the operation display of the relay to the operation display of the relay 3 as a new accident.
The same operation is performed according to I).

Although the above-described embodiment is configured by hardware, it is needless to say that the present invention is not limited to this and can be realized by software. In a protection relay device such as a bus protection device or a transformer protection device that does not include the reclosing circuit 17, the same operation can be realized by inputting the output of the one-shot circuit 16 to the OR gate 15.

〔The invention's effect〕

According to the present invention, the operation from the trip command to the restart of the circuit breaker is regarded as the same accident, and the operation display of the relay is updated each time a new accident occurs. An operation display circuit of the electric device can be obtained.

[Brief description of the drawings]

FIG. 1 is an operation display circuit diagram of the protection relay device of the present invention, and FIG.
FIG. 3 is a time chart of the operation display circuit, and FIG. 3 is an operation display circuit diagram of the conventional protection relay device. 1,2,3… Relay 4… Trip command circuit 5,6,7,19… AND circuit (AND gate) 8,9,10… Operation display holding circuit 11,12,13… … Display 15 …… OR circuit (OR gate) 16… One shot circuit 17… Reclose circuit 18 …… Reversal circuit (NOT gate)

Claims (3)

(57) [Claims] 1. An operation display circuit of a protection relay device having an operation display holding circuit for holding an indication of which of a plurality of relays operating upon detection of an accident in a power system caused an trip of a circuit breaker, An operation display circuit of the protection relay device, further comprising: display canceling means for outputting a holding release command to the operation display holding circuit for a predetermined time on condition of a trip command to the circuit breaker. 2. The operation display holding circuit according to claim 1, wherein said display canceling means issues a holding cancel instruction to said operation display holding circuit for a predetermined time under a condition of said trip command when a reclosure circuit of said circuit breaker is not in operation. 2. The operation display circuit of the protection relay device according to claim 1, wherein the operation display circuit outputs the signal. 3. The circuit according to claim 1, wherein said display canceling means includes a first circuit for outputting a predetermined time in response to a trip command to said circuit breaker, and a reclosing circuit of said circuit breaker not being activated. And a third circuit for outputting a hold release command to the operation display holding circuit when the outputs of the first and second circuits are established. 2. An operation display circuit of the protection relay device according to claim 1.