JPH0522850A - Apparatus for countermeasure against breaker operation failure - Google Patents

Abstract

PURPOSE:To avoid the loss of fail-safe conditions or the failure of ordinary monitoring even if a bus-bar is shutdown by selective cut-off at the time of breaker operation failure by a method wherein the failure detection condition of a line protective device is converted into a one-shot signal. CONSTITUTION:When a failure detection condition 6d is inputted from a line protective device when a breaker operation is failed, a signal 6e is outputted by a one-shot timer 15 for a certain period (t2). With this constitution, even if a bus-bar is shutdown by selective cut-off at the time of breaker operation failure and the failure detection condition 6d is outputted continuously, the operation of a fail-safe relay 32 is not continued and the loss of fail-safe conditions or the failure of ordinary monitoring can be avoided. Further, in accordance with a time chart, the setting time (t2) of the one-shot timer 15 must be shorter than the setting time (t3) of an ordinary monitoring failure detection timer 16, i.e., (t3)>(t2), and longer than the setting time (t1) of a breaker operation failure detection timer 9, i.e., (t2)>(t1).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit breaker non-operation countermeasure device having an automatic monitoring function, and in particular, in a device that constitutes a trip circuit with the fault detection condition of a line protection device as a fail-safe, the fault detection condition due to a system stop operates. The present invention relates to a circuit breaker non-operation countermeasure device that does not lose the fail-safe condition even if it is continued and does not constantly detect a monitoring failure.

[0002]

2. Description of the Related Art When an accident current cannot be cut off when a breaker is defective, the accident current can be removed at high speed due to equipment damage due to the accident current and expansion of the accident range, widening of the range of power outages, and spread to the entire power system. It is necessary to cut off the selection properly as well.

In general, measures for failure of accidental interruption due to malfunction of the circuit breaker, etc., depend on protection of the far-end backup equipment.
As described above, the breaker non-operation countermeasure device is applied to the breaker of the important electric station where the accident ripple due to the failure of the breakage is remarkably expanded. The causes of failure to shut off at the time of an accident are as follows. (1) Faulty circuit breaker trip circuit disconnection, short circuit, faulty pallet switch, D
C Control power supply failure, etc. (2) Defective mechanical operation system of circuit breaker Defective operating mechanism, decreased operating pressure, etc. (3) Defective main interrupting part Flashover between poles after opening the main interrupting part due to multiple lightning. Interruption failure due to short-distance accident or breaker breakage.

The circuit breaker non-operation measure deals with the failure of the circuit breaker due to the above-mentioned failure cause, and FIG. 2 is an example of a basic circuit configuration diagram thereof. That is, as shown in the figure, lines 2a, 2b and 2c are connected to the bus bar 1 via circuit breakers 3a, 3b and 3c, respectively. The line protection device 6 includes the voltage from the transformer 5 provided on the bus bar 1 and the line 2c.
The current of the current transformer 4a provided in the above is input. Also, track 2
The output of the current transformer 4b provided at c is the bus tie breaker CB7.
It is configured to be input to the overcurrent relay 8 via. The output 6t of the line protection device 6 and the output 8i of the overcurrent relay 8 are the settling time t _{1 of the} breaker inoperative judgment timer 9.
By continuing the above, it is determined that the circuit breaker is not operating, the trip command 9t is output, and the circuit breakers 3a and 3b connected to the same bus bar 1 are blocked to eliminate the accident.
The overcurrent relay 8 is added to prevent malfunction because the malfunction of the circuit breaker malfunction prevention device has a significant effect on the system.

Further, the interrupting command from the circuit breaker non-operation countermeasure device is normally selected and interrupted through the control circuit of the busbar protection device. The cutoff method differs depending on the busbar method, but here, the selective cutoff by the double busbar standard method will be described with reference to the circuit configuration diagram of FIG.

FIG. 3 is a circuit diagram of a double bus system. If an accident F occurs on the line L1 and the circuit breaker CB1 fails to block, the bus tie circuit breaker CB7 and the bus bar 1
The circuit breakers CB3 and CB5 connected to a are cut off to eliminate the accident. L2, L3, L4 are lines, C
B2, CB4, CB6 are circuit breakers connected to the bus bar 1, T
1, T2 are transformers.

The above explanation is about the basic idea of the circuit breaker non-operation measure. Next, referring to FIG.
The circuit breaker failure detection circuit and the trip circuit of (b) will be briefly described.

When an accident occurs on the track, the track protection device 6
Detects an accident and outputs a trip command to the circuit breaker, and at the same time trips the command signal 6
It outputs a, 6b, 6c and an accident detection condition signal 6d. In the circuit breaker non-operation countermeasure device, the trip command conditions 6a, 6b, 6c, 6d and the overcurrent relay output 0C1,0
By AND condition between C2,0C3 is (operation more breaker) settling limit t ₁ or more breaker inoperative determination timer 9 continues to detect a breaker inoperative, by selecting shutdown circuit 21 of the busbar protection device , The trip command relay 31 of the circuit breaker connected to the same bus bar is operated. The trip circuit considers the influence on the system when the circuit breaker non-operation countermeasure device malfunctions, as shown in FIG. 4 (b). The fail-safe relay (accident detection condition) 32 and the above-mentioned cutoff command relay 3
A malfunction is prevented by configuring 1 as an AND condition. The fail safe relay 32 also serves as the fail safe relay of the busbar protection device. This is because the cut-off circuit of the device is used to perform selective cut-off to eliminate accidents, and it can also be used as a fail-safe relay. However, in the case where the busbar protection device cannot detect an accident, such as an accident at the end of the line (accident at the other end), the fail-safe relay 32 does not operate.
Since the circuit breaker cannot be tripped and the accident cannot be removed, as a countermeasure, the accident detection condition 6d, which is taken in by the line protection device for judgment of the interruption failure detection, is used as a fail-safe relay. It constitutes a circuit.

In general, a protective device, especially an all-static type or digital type device, has an automatic monitoring function to detect defects early and improve the reliability of the device. That is, as shown in FIG. 4 (c), the circuit breaker non-operation countermeasure device also constantly monitors the contacts of the fail-safe relay 32 and the circuit break command relay 31 to improve reliability. The specific method of automatic monitoring can be divided into monitoring and inspection. Monitoring constantly checks the presence of abnormalities in the relay.For example, the final output of the relay output, which should always be inactive, is constantly monitored. It outputs an alarm. However, since the final output of the relay operates naturally in the event of a system fault, it is necessary to continue operation for longer than the system fault duration in order to determine that the relay is abnormal.
The inspection is to judge whether the operation is good or not by applying a simulated input to the relay at a constant cycle, which is different from the normal case. This is necessary because the relay is always inoperative as the final output, and it is possible to find a malfunction of the relay in advance.

[0010]

Therefore, in the case of the circuit breaker non-operation countermeasure device shown in FIG. 4 having the above-mentioned automatic monitoring,
When an accident occurs in the line, the line protection device 6 of the line detects the accident, and at the same time, the circuit breaker of the line is tripped, and at the same time, the circuit breaker non-operation countermeasure device is provided with the accident detection condition 6
d, the cutoff command conditions 6a, 6b, 6c are output. In the circuit breaker inoperative device, the outputs 6a, 6b, 6c, 6d from the line protection device 6 and the overcurrent relay output 0C1,
When the AND condition of 0C2 and 0C3 continues for the settling time t ₁ or more of the breaker malfunction determination timer 9, it is determined that the breaker is malfunctioning, and the break command relay 31 is activated. The fail-safe relay 32 is a busbar protection device 11,1.
It operates with the output of the accident detection conditions 11a and 13a of 3 or the accident detection condition 6d of the line protection device, and is connected to the circuit breaker non-operation line when the AND condition is satisfied with the operation of the interruption command relay 31 described above. Select the bus line to cut off and remove the accident. Therefore, the fault detection conditions 11a, 13b, and 6d of the busbar protection device and the line protection device connected to the stop busbar continue to operate without the busbar voltage. As a countermeasure, in the busbar protection devices 11 and 13, the busbar voltage is 3
There are provided all-stop detection circuits 12 and 14 which lock the output when the unconditional condition is continued for a certain period of time to determine that all the stops have occurred.

However, the accident detection condition 6 of the line protection device 6
d is not always locked on the sending side. In order to perform the full stop lock on the receiving side, the receiving side cannot determine which busbar the accident detection condition 6d is connected to, and the full stop locking by the busbar protection devices 11 and 13 is not performed. Therefore, the accident detection condition 6 of the line protection device 6
The output of d is continued without the bus voltage due to the stop of the bus, and the fail-safe relay 32 continues to operate. Therefore, the fail-safe relay condition will be lost. Also, FIG.
Since the contact make of the fail-safe relay 32 continues for the settling time t ₃ of the constant monitoring timer 16 in the constant monitoring circuit of (c), the constant monitoring failure of the output circuit is detected,
A problem occurs that the device is locked and the display alarm is output.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a circuit breaker non-operation countermeasure device that uses an accident detection condition from a line protection device as a fail-safe condition. It is an object of the present invention to provide a circuit breaker non-operation countermeasure device that prevents loss of the fail-safe relay condition even if the bus stops due to selective blockage due to removal, and does not always cause monitoring failure.

[0013]

In order to achieve the above-mentioned object, the present invention uses an accident detection condition of a line protection device and a breaker trip command condition as a starting condition, and the accident current continues for a certain period of time. In the circuit breaker non-operation countermeasure device, which detects the circuit breaker failure and opens the other circuit breaker connected to the same bus bar, it outputs the accident detection condition from the line protection device in the one-shot circuit for a certain period of time. It is characterized by being configured as described above.

[0014]

According to the present invention, the one-shot circuit outputs the accident detection condition from the line protection device used for the fail-safe relay only for a certain period of time, thereby stopping one bus bar due to the selective interruption during the interruption failure. Thus, even if the accident detection condition is a continuous output, by operating the fail-safe relay for a certain period of time, it is possible to prevent loss of the fail-safe condition and prevent constant monitoring failure.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a circuit breaker non-operation countermeasure device according to an embodiment of the present invention. In the figure, reference numerals corresponding to those in FIG. 4 have the functions described in FIG. 4, and detailed description thereof will be omitted.

Reference numeral 15 is a one-shot timer which, when a signal is input, outputs only for the settling time t ₂ . Accident detection condition 6d from the line protection device when shut off
, The one-shot timer 15 outputs the output signal 6e for a certain time t _{2 to} stop the busbar due to the selective interruption due to the circuit breaker not operating.
This is to prevent the fail-safe relay 32 from continuing to operate even if d continues to be output.

As described above, if the accident detection condition from the line protection device is converted to the wasshot signal, even if the single bus bar is stopped due to selective interruption as a measure against circuit breaker malfunction,
It is possible to prevent the loss of the fail-safe relay condition and prevent the constant monitoring circuit of the circuit breaker non-operation countermeasure device from detecting a defect.

FIGS. 5A and 5B are time charts thereof. First, in the time chart of FIG.
When the circuit breaker does not operate, the fault detection condition 6d of the line protection device continues to output due to no bus voltage due to one bus stop due to selective interruption, and the fail-safe relay 32 continues to operate and loses the fail-safe condition function. Further, the contacts of the fail-safe relay 32 continue to be made, and the contact make time exceeds the settling time t ₂ of the constant monitoring timer 16, resulting in failure of constant monitoring of the output circuit. FIG. 5B is a time chart according to the present invention. The one-shot timer 15 is applied to the accident detection condition 6d of the track protection device.
With one-shot signal 6e for a predetermined time t ₂ at, 6d is so not the operation of the fail safe relay 32 and continued as an output continuous, constant monitoring failure of loss prevention or output circuit of the fail-safe condition Will be prevented. Further, as can be seen from the time chart, the settling time t ₂ of the one-shot timer 15 needs to be t ₃ > t ₂ from the settling time t ₃ of the constant monitoring failure detection timer 16. Further, it is necessary to set t ₂ > t ₁ from the settling time t _{1 of the} breaker inactivity detection timer 9.

In the above embodiment, the one-shot signal is converted into the one-shot signal by the one-shot timer. However, the one-shot signal can be converted into the one-shot signal even if the accident detection condition continues for a certain time.

[0021]

As described above, according to the present invention, the fault detection condition of the line protection device used for the fail-safe relay is converted into a one-shot signal, so that the bus line is stopped by the selective interruption during the interruption operation. It is possible to provide a circuit breaker non-operation countermeasure device that does not always cause a monitoring failure without losing the safe condition.

[Brief description of drawings]

FIG. 1A is a circuit configuration diagram of an embodiment of the present invention,
(B) is a trip circuit diagram thereof, and (c) is a circuit diagram for constantly monitoring both contacts of the fail-safe relay and the interruption command relay.

FIG. 2 is a circuit configuration diagram of a conventional breaker not operating.

FIG. 3 is a circuit configuration diagram of a conventional double bus bar type circuit breaker inoperative.

FIG. 4A is a circuit configuration diagram of a conventional circuit breaker non-operation countermeasure device, FIG. 4B is a trip circuit diagram thereof, and FIG. 4C is a circuit for constantly monitoring both contacts of the fail-safe relay and the interruption command relay. Fig.

5A is a conventional time chart, and FIG. 5B is a time chart of the present invention.

[Explanation of symbols]

6 ... Track protection device, 9 ... breaker non-operation determination timer,
11, 13 ... Busbar protection device, 12, 14 ... Total stop detection circuit, 15 ... One-shot tire, 16 ... Constant monitoring tire, 21 ... Selective cutoff circuit, 31 ... Cutoff command relay,
32 ... Fail-safe relay.

Claims (1)

Claims: 1. The fault detection condition of the line protection device and the breaker trip command condition are used as starting conditions, and if the fault current continues for a certain period of time, a faulty disconnection is detected and the same busbar is detected. In the circuit breaker non-operation countermeasure device that measures the accident elimination by opening the other circuit breaker connected, the one-shot circuit is configured to output the accident detection condition from the line protection device only for a certain period of time. Breaker malfunction prevention device.