JPH03277116A - Re-closed circuit relay - Google Patents

Abstract

PURPOSE:To shorten the time required for detection of a permanent trouble by monitoring an earth current flowing in a cable shielding layer by a re-closed circuit relay for disconnection of the faulty block only by the breaking operation of a breaker without getting the faulty block in conduction again. CONSTITUTION:In the case that a short circuit happens in a first block of a distribution line, a greatly large current flows in the distribution line and an earth cable 8. On the side of the distribution line, an over-current relay 4 located just before a breaker 1 operates due to the trouble, sending an operation command to a re-closed circuit relay 6 for switching a breaker 'OFF' to stop a transmission of electrical energy to the distribution line. On the other hand, a current flows in the earth cable 8 and therefore a grounding over-current relay 7 works. The re-closed circuit relay 6, being prohibited by a signal sent from the grounding over-current relay 7 from operating, does not send the 'siwtch ON' command to the breaker 1. Therefore, re-closing of the circuit is not conducted and disconnection of the trouble block is finished.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention provides a method for solving problems when a short circuit or ground fault occurs in a distribution line.
This relates to a method of re-closing the circuit by connecting it to the intoxicated electric tile that caused this accident.

[Prior Art] Figure 2 shows the configuration of a conventional power distribution line. The distribution line has circuit breaker 1
2 section switch 2. Overcurrent relay 4. Directional ground fault relay5.
It is composed of a re-closing relay 6.

Place the distribution line wire 1, which circuit breaker 1 is the most R? The section sandwiched between the division switches 2 of the sword is called the first section, and in the case of Haton, most of this section is laid with cables 3. Hereinafter, a series of operations in the case of a short circuit accident will be described. In the case of a ground fault accident, the operation will be performed by the directional ground fault relay 5 instead of the overcurrent relay 4.

If there is a short-circuit accident in the branch section, a very large current will flow through the distribution line. The overcurrent relay power supply 4 detects the accident, sends a "cut" command to the interrupter 1Elr device 1, and recloses the circuit! ! ′
An operation command is sent to the device 6. This signal turns off the circuit breaker 1, and power transmission to the wiring is stopped. Reclosing relay 6 is overcurrent! 1! It operates upon receiving a signal from the electric appliance 4 and sends an "in" command to the circuit breaker 1 for a certain time period. Circuit breaker 1
is re-energized by this signal.

When circuit breaker 1 becomes energized, the west AT line is energized, or the fault in the first section is often not eliminated, and the fault continues, so circuit breaker 4 shuts off the overcurrent relay. This signal causes the circuit breaker 1 to trip again. In this way, when an accident is detected by the circuit breaker and a cut command is sent to the circuit breaker 1, the reclose relay 6 recognizes this and prohibits the output of the switch command to the circuit breaker 1. I was careful not to re-inject l. In the conventional reclosing method, even if a fault occurs in a section of a distribution line, the operations from detection of the fault section to cutting the lines and transmitting power to the healthy section are all the same.

[Problem to be solved by the invention] In the case of a ground fault accident in a wiring line, an accident in the laid cable part will result in a permanent* failure, and even though there is no possibility of the accident being eliminated, the accident classification due to re-closing. It took a long time to detect a permanent accident because it required detection and cutting and cutting operations. Additionally, there was a point that it was undesirable to energize the permanent accident section.

[Means for solving the problem] Utilizing the fact that the first section of the distribution line spring is also a cable cable, the earth current in the cable shielding layer is also monitored by a reclosing device.

[Example] Figure 1 shows the configuration of the wiring according to the present invention. The T distribution line has 12 circuit breakers for opening and closing. Overcurrent station 4. Directional ground fault relay5. Consisting of a reclosing relay wire 6, in addition to the conventional distribution line, a ground wire 8 is pulled out from the layer 3 of the cable 3, a signal is taken out from the ground wire 8, and a ground fault overcurrent 'A connection head 7 is drawn out. 9. i-Tru. This distribution line? A cable 3 is laid between the straw section, which is the section sandwiched between the circuit breaker 1 and the first sectional opening/closing section 2, and this section.

The following describes the series of actions in the case of a short circuit accident-5.
Or, in the case of a ground fault, the directional ground fault relay 5 operates instead of the overcurrent relay 4. If a short-circuit accident were to occur in the straw section of the distribution line, a very large current would flow through the distribution line, and at the same time, the ground wire S1, which was drawn from the cable 3 and the cable 3, would also flow. On the Nishimigami electric line side, overcurrent relay 4 is installed immediately before circuit breaker 1.
is activated due to a fault, and sends a "cut" command to the circuit breaker 1 and an operation command to the reclosing relay 6.A signal from the overcurrent relay 4 causes the circuit breaker 1 to "cut" and power transmission to the distribution line is stopped. Current also flows through the ground wire 8, and a signal is transmitted to the ground fault overcurrent relay 7, which operates and sends a signal to the reclosing relay 6t.The reclosing 28♀ stray current relay 6 is the overcurrent relay Despite the self-commands of the breaker 1 and others, the operation was prohibited by the signal sent by the ground fault overcurrent relay 7, and the ``in'' command was not sent to the circuit breaker 1, and the reclosing operation was not performed. This will no longer be done, and the crossing operation in the accident section will end.

[Effect of the invention] According to this invention, when a short circuit accident occurs in a section of a distribution line, the fault section can be cut off without energizing it again, compared to the disconnection operation of the fault section using the conventional re-closing method. Since the accident section is cut by simply cutting the vessel and making sweetfish, the time required is shortened, and when the earth fault overcurrent relay is activated, it can be determined that the accident occurred in the first section of the distribution line. It may take some time to recover.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a power distribution line constructed based on the present invention, and FIG. 2 is a block diagram of a conventional power distribution line. 1: Circuit breaker 2 Two-section switch 3: Keral 4: Overcurrent flJX electrical two-way ground fault relay: Reclosing relay: Ground overcurrent relay: Earth wire

Claims (1)

[Claims] In an electrical equipment comprising a first relay that outputs a signal due to a fault current at the time of a ground fault or short circuit accident in a distribution line, and a circuit breaker that opens the distribution line in response to a signal from the first relay, by a reclosing relay that operates after a certain period of time after recognizing the signal from the first relay;
In a re-closing relay system in which the distribution line is closed again by closing the circuit breaker, a second circuit breaker outputs a signal by a ground fault current flowing through a grounding wire connected to a cable layer of the distribution line when an accident occurs. using the relay of the second
A re-closing relay method, characterized in that when a signal from a relay is given to the re-closing relay, the re-closing relay prohibits the re-closing of the distribution line of the circuit breaker.