JPS63148820A - Restoration system of grounding failure of bus bar - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a busbar ground fault recovery system.

[Conventional technology]

FIG. 3 shows a conventional example. That is, this busbar ground fault recovery system connects the busbar 52 to the secondary side of the main transformer 50 via the main transformer secondary side circuit breaker 51, and connects a plurality of distribution line circuit breakers 54 to the bus m52. A feeder line 55 is connected to the load side of the distribution line breaker 54, respectively.

This feeder line 55 is provided with a ground fault direction relay 56,
A ground fault on the load side is detected by the ground fault direction relay 56.

Further, a ground fault in the feeder line 55 and bus m52 between the ground fault direction relay 56 and the main transformer secondary circuit breaker 51 is detected by a ground fault overvoltage relay 57 connected to the bus bar 52.

In the case of a ground fault in the feeder line 55 between the ground fault direction relay 56 and the distribution line circuit breaker 54, the selection control relay 58 linked to the detection operation of the ground fault overvoltage relay 57 switches each distribution line circuit breaker. 54 are sequentially cut off, and the feeder line 55 that has a ground fault is determined based on whether the ground fault overvoltage relay 57 has stopped its ground fault detection operation.

Further, if a ground fault in the feeder line 55 is not detected in the above operation, the ground fault occurs in the bus bar 52, so the main transformer secondary circuit breaker 51 is shut off.

In addition, 59 is an installation type voltage transformer, 60 is a ground fault phase discrimination relay, and 61 is an overcurrent relay.

[Problem that the invention seeks to solve]

In the case of a ground fault accident in a feeder line 55, this busbar ground fault recovery system
The distribution line breakers 54 of the other feeder lines 55 are turned on again to recover. Afterwards, the worker
5. Replacement work will be carried out.

However, in this busbar ground fault recovery system, when the main transformer secondary circuit breaker 51 is shut off, all the loads connected to the feeder line 55 will experience a power outage. It had the disadvantage that the area was wide (and it took a long time to restore lines that had not experienced a ground fault).

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a busbar ground fault recovery system that can reduce the power outage range and shorten the recovery time for lines that have not experienced a ground fault.

[Means for solving problems]

The busbar ground fault recovery system of the present invention includes a main transformer, a main transformer secondary circuit breaker whose power supply side is connected to the secondary side of the main transformer, and a main transformer secondary circuit breaker whose power supply side is connected to the secondary side of the main transformer. A plurality of bus disconnection switches each having a power supply side connected to a first busbar connected to the load side, and a power supply connected to a second busbar each connected to the load side of each busbar disconnection switch. a plurality of distribution line circuit breakers connected to each other, a feeder line connected to the load side of each of these distribution line circuit breakers, and an auxiliary bus bar that is wired separately from the first bus bar and the second bus bar. The auxiliary busbars are connected to the secondary side of the main transformer via a circuit breaker, and are connected to the feeder lines via auxiliary busbar disconnectors, and the ground of the first busbar is a ground fault detection means for detecting a fault current; and a first circuit breaker for sequentially interrupting each of the distribution line circuit breakers through a detection operation of the ground fault detection means to determine which feeder line has experienced a ground fault among the plurality of feeder lines. control means, and when the first control means does not determine a ground fault in the feeder line, the detection operation of the ground fault detection means sequentially shuts off the busbar disconnecting switches and the plurality of second A disconnector for an auxiliary bus bar of the feeder line connected to the second bus bar that has a ground fault through the distribution line breaker, and a disconnector for the auxiliary bus bar that is connected to the second bus bar that has a ground fault among the bus bars. a second control means for closing the circuit breaker; and a second control means for closing the secondary circuit breaker of the main transformer and closing all the auxiliary busbars when the second control means does not determine a ground fault of the second busbar. It is provided with a new circuit switch and a third control means for closing the auxiliary bus circuit breaker.

[Function] According to the configuration of the present invention, the second bus bar is connected to the first bus bar via the bus disconnection switch, and the feeder line is connected to the second bus bar via the distribution line breaker. At the same time, a ground fault in the second bus bar is detected by the second control means, and power is supplied to the feeder line of the second bus bar without a ground fault by turning on the bus disconnection switch again. In addition, since the first busbar and the second busbar where the grounding fault occurred supply power to the feeder line through the auxiliary busbar, it is possible to reduce the area of power outage and shorten the recovery time for lines that have not caused the grounding fault. can.

〔Example〕

An embodiment of the present invention will be described based on FIGS. 1 and 2. In other words, this busbar ground fault recovery system includes the main transformer 1 and the secondary side of the main transformer 1. :, a main transformer secondary circuit breaker 2 connected to the source side, and a plurality of buses connected to the power supply side to the first bus 3 connected to the load side of the main transformer secondary circuit breaker 2. Disconnector for disconnection 4a, 4b
, a plurality of distribution line circuit breakers 6a to 6r whose power supply sides are connected to the second bus 5 which is connected to the load side of each of these bus disconnection switches 4a and 4b, and each of these distribution lines. The feeder line 7 connected to the load side of the circuit breakers 6a to 6f
The first busbar 3 and the second busbar 5 are wired separately and connected to the secondary side of the main transformer 1 via an auxiliary bus circuit breaker 8, and are connected to the feeder line 7 with a disconnector for the auxiliary busbar, respectively. The auxiliary bus bar 10 connected through the circuits 9a to 9f, the ground fault detection means 11 that detects the ground fault current of the first bus vA3 in the event of a ground fault fault, and the detection operation of this ground fault detection means 11 detect each wiring. A first step that sequentially interrupts the wire circuit breakers 63 to 6f to determine which feeder line 7 has a ground fault among the plurality of feeder lines 7.
control means 12, and when the first control means 12 does not determine a ground fault in the feeder line 7, the detection operation of the ground fault detection means 11 sequentially shuts off the bus disconnection switches 4a and 4b, and The second bus bar 5 that has a ground fault among the second bus bars 5
The auxiliary bus disconnectors 9a to 9f and the auxiliary bus circuit breaker 8 of the feeder line 7 connected to the second bus 5 which has a ground fault through the distribution line circuit breakers 6a to 6r.
and a second control means 13 that closes the main transformer secondary side circuit breaker 2 and shuts off the main transformer secondary side circuit breaker 2 when the second bus 5 is not determined to have a ground fault. It is provided with a third control means 14 that closes the disconnectors 9a to 9f and the auxiliary bus circuit breaker 8.

This busbar ground fault recovery system is mainly used in substations.

The busbar disconnecting disconnectors 4a and 4b are opened and closed by a motor operating device, and have a contact point at position 3 M, so that when opened, the second busbar 5 is automatically grounded.

The ground fault detection means 11 is an embodiment of a ground fault overvoltage relay.

In the figure, 15 is a ground fault direction repair appliance, 16 is a first control means 1
2, a selection control relay forming a part of 2, 17 a ground fault phase discrimination electric device, 18 a grounding type instrument transformer, 19 a zero-phase current transformer, 2
0 is an overcurrent relay.

Said first control means 12. A flowchart of the sequence control device including the second control means 13 and the third control means 14 is shown in FIG.

In FIG. 2, before the first control means 12 operates, it is determined whether the ground fault detection means 11 has operated (step 31). If the result of the determination is N, that is, non-operation, the determination in step S1 is repeated again. If it is Y, that is, operation, a confirmation time of about 1 to 10 seconds elapses (step S2). After the elapse of that time, it is determined again whether or not the ground fault detection means 11 has operated (step S3). The reason why the two-stage determination is performed in this way is to prevent the ground fault detection means 11 from malfunctioning due to surges or the like.

If the determination in step 3 is N, the determination in step S1 is made. If Y, it is assumed that a ground fault has occurred and the first
The control means 12 of is operated.

In the first control means 12, the selection control relay 16 is activated by the detection operation of the ground fault detection means 11 (step 5).
4) The distribution line breakers 6a to 6f are sequentially tripped and cut off by the operation of the 0 selection control relay 16 (step s
5) It is determined whether or not the ground fault detection means 11 is in operation for each interruption (step S6). If Y, that is, it is in operation, it is determined whether or not the final distribution line circuit breaker 6f has been tripped (step 37). Y, that is, when the distribution line circuit breaker 6f is tripped, since the ground fault detection means 11 is still operating, it means that no ground fault has occurred in the feeder line 7, and the second bus 5 or the first Bus line 3
Since it is estimated that a ground fault has occurred, the second control means 13 is operated.

If the ground fault detection means 11 is N, that is, it stops operating in step S6, it is determined which of the distribution line circuit breakers 6a to 6f caused a ground fault in the feeder line 7 that was cut off, and the ground faulted feeder line No. 7 distribution line circuit breaker 6a
In order to prevent ~6f from being re-closed, the ground faulted feeder line 7 is re-closed (step S8), and the line breakers 63-6r are re-closed to the healthy feeder line 7 (step S8). S9), the ground-faulted feeder line 7 is also displayed, and a request is made to replace the feeder line 7 (step 510).

In the second control means 13, since this is a case where the ground fault detection means 11 in the first control means 12 is in operation and has not stopped operating, the bus disconnection switch 4a.

4b are opened in sequence. That is, first, the bus disconnection switch 4a is opened (Step 311), and it is determined whether or not the ground fault detection means 11 is operating (Step 5j2). The circuit disconnector 4b is opened (step 513), and it is determined whether the ground fault overvoltage relay 11 is operating (step 314). At this time, if Y, that is, it is in operation, it means that a ground fault has occurred on the second bus 5, and at the same time it is presumed that a ground fault has occurred on the bus 3, so the third control means 14 is activated. It will be necessary to do so.

If the judgment in step 12 as to whether or not the ground fault detection means °11 is operating is N, that is, the operation has stopped, the distribution line circuit breakers 6a to 6
This means that the second bus bar 5 connected to c has a ground fault. Therefore, since there is no ground fault in the second bus bar 5 of the distribution line circuit breakers 6d to 6r, the distribution line circuit breakers 6d to 6f are reclosed (
step 315).

Also, the auxiliary bus disconnectors 9a to 9c are closed, the auxiliary bus circuit breaker 8 is closed, and power is supplied from the auxiliary bus 10 to the feeder wires 7 of the open distribution line circuit breakers 6a to 6c (step 516). Also, distribution line circuit breakers 6a to 6c
It is displayed that the second bus bar 5 connected to the
request replacement work for busbar 5 (step 517).
.

Similarly, if the determination as to whether the ground fault detection means 11 is in operation in step S14 is N, that is, if it has stopped operating, it means that the second bus 5 connected to the distribution line circuit breakers 6d to 6f has experienced a ground fault. Therefore, the bus disconnection switch 4a is turned on again (step 318), and the distribution line circuit breakers 6a to 6C are turned on again (step 519). The auxiliary bus disconnectors 9d to 9f are closed, the auxiliary bus circuit breaker 8 is closed, and power is supplied from the auxiliary bus to the feeder wires 7 of the open distribution line circuit breakers 6d to 6f (step 520). Also, it displays that the second bus bar 5 of the distribution line circuit breakers 6d to 6f has a ground fault, and requests that the second bus bar 5 be replaced (step 521).

In the third control means 14, if the ground fault detection means 11 is in operation due to the opening of the bus disconnection switch 4b as described above, the main transformer The secondary circuit breaker 2 is shut off (step 522). The auxiliary bus disconnectors 93 to 9f are closed (step 523), the auxiliary bus circuit breaker 8 is closed, and power is supplied to all feeder lines 7 from the auxiliary bus (step 524). It also displays that the first bus 3 has a ground fault, and requests replacement work for the first bus 3 (step 525).

Note that detection of a ground fault on the load side from the ground fault direction relay 15 is the same as in the conventional case.

According to this embodiment, the second bus bar 5 is connected to the first bus bar 3 via the bus bar disconnection switches 4a and 4b, and the second bus bar 5 is connected to the second bus bar 5 via the circuit breakers 63 to 6r for distribution lines. At the same time, the second control means 13 detects a ground fault in the second bus bar 5, and the second bus bar 5, which has no ground fault accident, reconnects the bus disconnection switches 4a and 4b. By turning on the power, the feeder line 7 is supplied with power. In addition, the first bus 3 and second bus 5, where the ground fault occurred, supply power to the feeder line 7 through the auxiliary bus 1O, so it is possible to reduce the area of power outage and shorten the recovery time for lines that have not caused the ground fault. can be achieved.

〔Effect of the invention〕

According to the busbar ground fault recovery system of this invention, the first
A second bus bar is connected to the bus bar via a bus disconnection switch, a feeder line is connected to the second bus bar via a distribution circuit breaker, and the second bus bar is connected to the second bus bar by the second control means. A ground fault is detected, and power is supplied to the feeder line of the second bus bar with no ground fault by turning on the bus disconnector again.

In addition, since the first busbar and the second busbar where the grounding fault occurred supply power to the feeder line through the auxiliary busbar, it is possible to reduce the area of power outage and shorten the recovery time for lines that have not caused the grounding fault. There is an effect that it can be done.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of one embodiment of the present invention, FIG. 2 is a flowchart of sequence control including first to third control means, and FIG. 3 is an explanatory diagram of a conventional example. ■...Main transformer, 2...Main transformer secondary side circuit breaker, 3
... First bus bar, 4a, 4b... Disconnector for disconnecting bus bar, 5... Second bus bar, 6a to 6f... Circuit breaker for distribution line, 7... Feeder line, 8 ... Auxiliary bus circuit breaker,
93-9f... Auxiliary bus disconnector, 10... Auxiliary bus bar, 11... Ground fault detection means, 12... First control means, 13... Second control means, I4. ...Third rule i
1 means ρ,, ゛I look at it.

Claims (1)

[Claims] A main transformer, a main transformer secondary circuit breaker whose power supply side is connected to the secondary side of this main transformer, and a first bus bar connected to the load side of this main transformer secondary circuit breaker. A plurality of busbar disconnection switches to which the power supply side is connected, and a plurality of distribution line circuit breakers to which the power supply side is connected to a second busbar each connected to the load side of each of these busbar disconnection disconnectors. , a feeder line connected to the load side of each of these distribution line circuit breakers, and the first
and the second busbar, and are connected to the secondary side of the main transformer via an auxiliary busbar circuit breaker, and are connected to the feeder line via an auxiliary busbar disconnector, respectively. an auxiliary bus bar, a ground fault detection means for detecting a ground fault current in the first bus bar in the event of a ground fault accident; and a detection operation of the ground fault detection means to sequentially interrupt each of the distribution line breakers to a first control means for determining which feeder line has a ground fault among the feeder lines; Determining which second bus bar has a ground fault among the plurality of second bus bars by sequentially shutting off separate disconnectors and connects the second bus bar which has a ground fault via the distribution line breaker. a second control means for closing the auxiliary bus disconnector for the feeder line and the auxiliary bus circuit breaker; A ground fault recovery system for a bus bar, comprising: third control means for shutting off a secondary side circuit breaker and closing all of the auxiliary bus disconnectors and the auxiliary bus circuit breaker.