JPH0576113A - Gas insulated switchgear - Google Patents

Abstract

PURPOSE:To provide a gas insulated switchgear in which high withstand voltage is ensured, workability is enhanced in inspection work, mechanical interlock circuit can be constituted readily between a high speed ground switch and a circuit breaker, and a transmission system can be protected positively. CONSTITUTION:A circuit breaker and a disconnector 2 are connected in series through a connecting bus 7 to the opposite ends of each transmission line. A line ground switch 4 is connected to the transmission line side of the disconnector 2. A high speed ground switch 3 is connected to the transmission line side of the disconnector 2 or between the disconnector 2 and the circuit breaker 1. The high speed ground switch 3 is disposed while being branched from the main circuit between the circuit breaker 1 and the transmission line thus forming a branch circuit. The high speed ground switch 3 is gas sectioned independently from the machines on the main circuit side, e.g. the connection bus 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-insulated switchgear, and more particularly, a continuous ground fault arc of an overhead power transmission line in the gas-insulated switchgear is commutated and interrupted, thereby enabling early operation by reclosing the circuit breaker. The present invention relates to a high-speed grounding switch.

[0002]

2. Description of the Related Art Recent power transmission systems are shifting from the ultra-high voltage class of 500 kV to the ultra-high voltage class of 725 kV and 1000 kV. In such a power transmission system, as the distance from other lines to be installed side by side or power lines of other phases of the same line becomes extremely high due to structural restrictions such as steel towers,
There is a risk that it will not be large compared to the voltage.

Usually, in a power transmission system up to about 500 kV class, when a ground fault occurs due to a lightning strike, each circuit breaker installed at the substations at both ends of the transmission line of each line is shut off to eliminate the ground fault current. Can be made However,
In the ultra-high voltage class of 725 kV to 1000 kV, as described above, the induced current from the transmission line of another healthy line is small because the distance from the transmission line of the other line or the other phase of the same line is small and the voltage is high. Flows. That is, if the circuit breakers at the substations at both ends of the accident point are simply broken, the induced current continues to flow in the transmission line and the arc continues as if the accident current remains. Therefore, the closing operation is performed again when the breaker is turned on. Therefore, in order to succeed in the reclosing operation, it is necessary to extinguish the continuous arc and cut off the induced current before the reclosing operation.

As one of the methods for this purpose, the applicant
First, after interrupting the accident current with a circuit breaker, turn on the high-speed earthing switch provided on the line side, and extinguish the induced current flowing in the continuous arc by commuting to this high-speed earthing switch, and then extinguish this high-speed earthing switch. It proposes a technique (Japanese Patent Application No. 3-229052) for breaking the induced current by opening the ground switch.
When such a technique is applied, the ground fault arc of the line can be completely eliminated by a series of operations of the high-speed grounding switch, and therefore, by reclosing the circuit breaker, the phase Can be returned to the operating state.

FIG. 7 is a single wire connection diagram showing the conventional gas-insulated switchgear described above, and FIG. 8 is a side view showing an example of equipment arrangement on one side of the power transmission line in the gas-insulated switchgear of FIG. Is. As shown in FIG. 7, the circuit breaker 1 and the disconnector 2 are connected in series to one end of the power transmission line 21 of the line, and the high speed grounding switch 3 and the line for line are connected to the power transmission line 21 side of the disconnector 2. The grounding switch 4 is connected, and the bushing 5 is connected to the power transmission line 21. On the other hand, the same configuration as the above is connected to the other end of the power transmission line 21 of the line. That is, the circuit breaker 11, the disconnector 12, the high-speed grounding switch 1
3 and the line grounding switch 14 are sequentially connected, and are connected to the power transmission line 21 by the bushing 15.

Further, as shown in FIG. 8, the circuit breaker 1, the disconnector 2, and the high-speed grounding switch 3 are arranged linearly in this order, and further connected to the line grounding switch 4 via the connecting bus 7. The bushing 5 is vertically arranged above the line grounding switch 4 which is connected. The power transmission line 21
Although not shown, the arrangement configuration of the devices at the other end of is similar to the configuration shown in FIG.

By the way, as a gas compartment in the gas-insulated switchgear of FIG. 7, generally, a gas compartment as shown by a broken line in the drawing can be considered. In FIG. 7, 6a-
6d shows an insulating spacer for gas division. That is, the circuit breaker 1 is independently gas partitioned by the insulating spacers 6a and 6b, and the disconnector 2 is individually gas partitioned by the insulating spacers 6b and 6c. The high-speed grounding switch 3 is collectively gas-divided by the insulating spacers 6c and 6d together with the connecting bus 7. The line grounding switch 4 is independently gas-divided by the insulating spacer 6d and the bushing 5. Further, the circuit breaker 11, the disconnector 12, and the line grounding switch 14 are individually gas-divided by the insulating spacers 16a to 16d and the bushing 15, and the high-speed grounding switch 13 and the connection bus bar 17 are collectively packaged. Gas compartment.

In the gas-insulated switchgear configured as described above, when a ground fault current flows at point A in the middle of the power transmission line 21 due to a lightning strike, as shown in FIG.
After shutting off 1, the high-speed grounding switches 3 and 13 are turned on, and the induced current flowing in the continuous arc is extinguished by commutating to the high-speed grounding switches 3 and 13, and then the high-speed grounding switches 3 and 13 are turned on. Open circuit to cut off induced current. By the series of operations of the high-speed grounding switches 3 and 13, the transmission line 2
Since the ground fault arc 1 can be completely removed,
Then, by closing the circuit breakers 1 and 11 again, the phase in which the accident occurred can be returned to the operating state.

[0009]

However, in the conventional gas-insulated switchgear described above, this occurs when the high-speed earthing switches 3 and 13 are turned on in order to commutate the induced current flowing in the continuous arc. There is a problem that decomposed gas and other decomposed products are mixed in the connecting bus bars 7 and 17 of the same gas section to lower the withstand voltage strength. Further, since the high-speed grounding switches 3 and 13 have a severe duty, the number of inspections is greater than that of other grounding switches, but it is necessary to perform gas treatment during such inspection work. In this case, the high-speed grounding switches 3 and 13 are collectively gas-divided together with the connecting buses 7 and 17, so that a wide range of gas treatment must be performed accordingly. As a result, the workability of the inspection work of the high-speed earthing switches 3 and 13 is low, and it takes a long time to carry out the work. Further, since the high-speed grounding switches 3 and 13 are connected so as to directly ground the main circuit, the inspection work cannot be performed unless the entire circuit is stopped. There is also a problem that the stop time of the entire circuit becomes long.

In the gas-insulated switchgear described above, in order to reliably protect the power transmission system, a mechanical interlock circuit is constructed by the high-speed grounding switches 3 and 13 and the circuit breakers 1 and 11. , It is important to properly link the two and carry out a series of responsibilities. However, in the linear arrangement as shown in FIG. 8, since the high-speed grounding switches 3 and 13 and the circuit breakers 1 and 11 are separated from each other, a mechanical interlock circuit for both can be formed. There was a difficult problem.

Further, in the high-speed earthing switches 3 and 13, it is assumed that the main busbar portion remains open even after the circuit is opened due to a malfunction such as an inability to open the circuit after the closing operation, an inability to operate in the incomplete closing state, or a melting damage of the contacts on the main bus side. In order to restore this line in the event of a failure such as the insulation performance not recovering, it is necessary to remove the high-speed grounding switch from the main bus and repair or replace it. In this case, in the arrangement shown in FIG. 8, there is a problem that a great deal of time is required for restoration work and the system must be stopped for that long time. Such a suspension of the system for a long time impairs the stable supply of electric power and causes great damage to society. In particular, in a UHV substation that handles an enormous amount of energy, the damage caused by the stoppage of the operation will be so great that the stoppage of operation for a long time was a very serious problem.

The present invention has been proposed in order to solve the problems of the prior art as described above, and an object thereof is to ensure high withstand voltage performance, improve workability of inspection work, and high speed. A gas-insulated switchgear capable of easily configuring a mechanical interlock circuit between a ground switch and a circuit breaker and reliably protecting a power transmission system. Further, in the event that an operation failure or a failure in the main body occurs in the high-speed earthing switch, it is also one of the objectives to shorten the system down time accompanying the restoration work as much as possible.

[0013]

A gas-insulated switchgear according to the present invention comprises a circuit breaker and a disconnector connected in series at both ends of each transmission line of a circuit, and a line for the transmission line side of the disconnector. In a gas-insulated switchgear in which a grounding switch is connected, and a high-speed grounding switch is connected between the disconnector and the transmission line side or between the disconnector and the circuit breaker, the high-speed grounding switch is fed from the circuit breaker. It is characterized in that a branch circuit is formed by branching with respect to the main circuit leading to the electric wire, and the high-speed grounding switch is separated from the main circuit side device to be gas sectioned. Further, it is desirable to provide a disconnecting device or a disconnector for disconnecting the main circuit and the high-speed grounding switch in the branch circuit.

[0014]

The operation of the present invention having the above construction is as follows. That is, by separating the high-speed earthing switch from the equipment on the main circuit side and partitioning it into gas, the decomposition gas and other decomposition products accompanying the turning on of the high-speed earthing switch,
Since it can be prevented from being mixed in the main bus side equipment such as the connecting bus bar, the initial withstand voltage performance can be secured.
Further, by independently dividing the high-speed grounding switch into the gas compartments, the gas processing range at the time of inspection work is significantly narrower than in the case where the gas is collectively compartmented together with the connecting bus bar. Therefore, the workability of the inspection work of the high-speed grounding switch in the gas-insulated switchgear of the present invention is high, and it can be completed in a short time, whereby the down time of the entire circuit accompanying the inspection work can be shortened. it can.

On the other hand, in the present invention, since the high-speed grounding switch is branched and arranged with respect to the main circuit to form a branch circuit, the high-speed grounding switch can be arranged in the vicinity of the circuit breaker. As a result, there is also an advantage that a mechanical interlock circuit between the high-speed grounding switch and the circuit breaker can be easily constructed. Therefore, by properly interlocking the high-speed grounding switch and the circuit breaker to perform a series of duties, the power transmission system can be reliably protected.

Further, since the high-speed earthing switch has a branch circuit structure in this way, in the event that an operation defect or a defect in the main body occurs in the high-speed earthing switch, the high-speed earthing switch is removed from the main circuit. It can be easily separated. Therefore, the recovery work in such a case can be completed in a short time, and the system down time accompanying this work can be shortened as much as possible. Especially, if a disconnecting device or disconnector for disconnecting the main circuit from the high-speed grounding switch is provided in the branch circuit, the main circuit continues to operate with the faulty high-speed grounding switch disconnected. Therefore, it is possible to shorten the downtime of the system accompanying the restoration work to the necessary minimum.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the gas-insulated switchgear according to the present invention will be described below with reference to FIGS. In this case, FIG. 1 is a single line connection diagram showing a gas compartment of an embodiment of the gas insulated switchgear according to the present invention, and FIG. 2 shows a device arrangement on one side of a power transmission line in the gas insulated switchgear of FIG. It is a side view (A) and a plan view (B) showing a part thereof. The same parts as those of the prior art shown in FIGS. 7 and 8 are designated by the same reference numerals.

First, as shown in FIG.
A circuit breaker 1, a disconnector 2, a high-speed grounding switch 3 and a line grounding switch 4 are sequentially connected to one end of 1, and a bushing 5
It is connected to the power transmission line 21 by. Further, according to the present invention, a branch circuit connecting bus 8 is connected to the connecting bus 7 connecting the circuit breaker 1 and the disconnector 2 to the bushing 5, and the branch circuit connecting bus 8 is further connected to a high-speed grounding switch. 3 are connected, and a branch circuit is formed by the high-speed grounding switch 3 and the branch circuit connecting busbar 8.

Further, the circuit breaker 1, the disconnecting switch 2, and the line grounding switch 4 are individually gas-divided by the insulating spacers 6a to 6d and the bushing 5 as in the prior art shown in FIG. On the other hand, according to the present invention, the high-speed earthing switch 3 is gas-separated independently of the connecting busbars 7 and 8 by the insulating spacer 6e arranged between the connecting busbars 8 and. As a result, the connecting buses 7 and 8 are independently gas-divided by the three insulating spacers 6c to 6e.

Further, as shown in FIGS. 2A and 2B, the circuit breaker 1, the disconnector 2, the connecting bus bar 7, and the line grounding switch 4 are linearly arranged in a line in this order. And
A bushing 5 is vertically arranged above the line grounding switch 4. Then, as shown in FIG. 2B, the branch circuit connecting bus 8 is L-shaped, whereby the high-speed grounding switch 3 connected to the tip of the branching circuit connecting bus 8 is located close to the circuit breaker 1. It is arranged in parallel with the circuit breaker 1 and constitutes a mechanical interlock circuit 9 between the high-speed grounding switch 3 and the circuit breaker 1.

On the other hand, the same constitution as the above constitution is connected to the other end of the power transmission line 21 of the line. That is, the circuit breaker 11, the disconnector 12, the high-speed grounding switch 13, and the line grounding switch 14 are sequentially connected, and are connected to the power transmission line 21 by the bushing 15. Further, the circuit breaker 11, the disconnector 12, and the line grounding switch 14 are individually gas-divided by the insulating spacers 16 a to 16 d and the bushing 15, and the high-speed grounding switch 13 is connected to the connection bus bar 18.
By the insulating spacer 16e arranged between and, the gas is partitioned independently of the connecting buses 17 and 18. As a result, the connecting buses 17 and 18 are independently gas-divided by the three insulating spacers 16c to 16e. The arrangement of these devices is not shown, but is the same as that shown in FIG.

In the present embodiment having the above-mentioned structure, the connection buses 7, 8, and 8 of the decomposition gas and other decomposition products generated when the high-speed earthing switches 3 and 13 are turned on.
Since the mixture into 17 and 18 can be prevented, the initial withstand voltage performance can be secured. In addition, by separating the high-speed grounding switches 3 and 13 independently from each other in this way to divide the gas,
Compared with the case where the gas is collectively divided together with the connecting buses 7 and 17, the gas processing range during the inspection work can be significantly narrowed. Therefore, the workability of the inspection work of the high-speed grounding switches 3 and 13 in the gas-insulated switchgear of the present embodiment is high and can be completed in a short time, whereby the down time of the entire circuit accompanying the inspection work can be shortened. Can be converted.

On the other hand, in the present embodiment, the high-speed earthing switches 3 and 13 are arranged in a branch circuit and arranged in the vicinity of the circuit breakers 1 and 11, and the high-speed earthing switches 3 and 13 and the circuit breakers 1 and 1 are arranged.
And a mechanical interlock circuit 9 together with 11.
Therefore, by properly interlocking the high-speed grounding switches 3 and 13 and the circuit breakers 1 and 11 to perform a series of responsibilities,
It is possible to reliably protect the power transmission system. In addition, since the high-speed grounding switches 3 and 13 have the branch circuit configuration as described above, when the high-speed grounding switches 3 and 13 are connected in series between the devices of the main circuit as in the prior art shown in FIG. Compared with, the high-speed grounding switches 3 and 13 can be easily separated from the main circuit. Therefore, in the event that an operation failure or a failure in the main body occurs in the high-speed earthing switches 3 and 13, the recovery work can be performed by easily disconnecting the high-speed earthing switches 3 and 13 from the main circuit in a short time. Can be significantly shortened compared to the conventional system, and the system downtime associated with this work can be greatly reduced.

The present invention is not limited to the above-mentioned embodiment, and the same excellent effects can be obtained by the following other embodiments.

For example, FIGS. 3 and 4 show disconnectors 2 and 12.
Instead of connecting the high-speed grounding switches 3 and 13 to the power transmission line 21 side, the embodiment in which the high-speed grounding switches 3 and 13 are connected between the disconnecting switches 2 and 12 and the circuit breakers 1 and 11 is shown. In this case, FIG. 3 is a single wire connection diagram showing a gas section of the gas insulated switchgear, and FIG. 4 is a side view (A) showing a device arrangement on one side of the power transmission line and a plan view (B) showing a part thereof. Is. Even in the case of such a connection configuration, the same operational effect as that of the above-described embodiment can be obtained.

FIGS. 5 and 6 show an embodiment in which disconnecting devices 10 and 20 are provided in place of the branch circuit connecting buses 8 and 18 in the embodiments of FIGS. 1 and 2. In this case, FIG. 5 is a single wire connection diagram showing a gas section of the gas insulated switchgear, and FIG. 6 is a side view (A) showing a device arrangement on one side of the power transmission line and a plan view (B) showing a part thereof. Is. According to this embodiment, in the event that a problem occurs in the high-speed earthing switches 3 and 13, the disconnecting devices 10 and 20 make it very easy to remove the high-speed earthing switches 3 and 13 from the main circuit, and the necessary minimum. It can be separated in a very short time.

Then, the high-speed grounding switch 3, which is in a defective state,
If 13 is separated in this way, the operation of the main circuit can be continued as it is, so that the recovery work can be completed during the continuous operation of the main circuit, and the system down time accompanying the recovery work can be reduced. It can be shortened to the required minimum. Therefore, it can greatly contribute to the stable supply of electric power, and is extremely effective especially in the UHV substation that handles a huge amount of energy. Further, in FIG. 5 and FIG. 6, the same operational effect can be obtained even when a disconnecting switch is provided instead of the disconnecting devices 10 and 20.

[0028]

As described above, in the present invention, the high-speed grounding switch is branched and arranged with respect to the main circuit to form a branch circuit, and the high-speed grounding switch is connected to the main circuit side device. Independent gas division ensures high withstand voltage performance and improves the workability of inspection work.
It is possible to provide a gas-insulated switchgear that can easily configure a mechanical interlock circuit between a high-speed grounding switch and a circuit breaker and can reliably protect the power transmission system. Further, in the event that an operation failure or a failure in the main body occurs in the high-speed earthing switch, it is possible to shorten the system stop time associated with the restoration work as much as possible.

[Brief description of drawings]

FIG. 1 is a single wire connection diagram showing a gas compartment of an embodiment of a gas insulated switchgear according to the present invention.

2 is a side view showing a device arrangement on one side of a power transmission line in the gas insulated switchgear of FIG. 1 and a plan view showing a part thereof.

FIG. 3 is a single wire connection diagram showing gas compartments of different embodiments of the gas insulated switchgear according to the present invention.

4 is a side view showing a device arrangement on one side of a power transmission line in the gas insulated switchgear of FIG. 3 and a plan view showing a part thereof.

FIG. 5 is a single wire connection diagram showing a gas compartment of a gas insulated switchgear according to a further different embodiment of the present invention.

6 is a side view showing a device arrangement on one side of a power transmission line in the gas insulated switchgear of FIG. 5 and a plan view showing a part thereof.

FIG. 7 is a single wire connection diagram showing a gas section of an example of a conventional gas insulated switchgear.

8 is a side view showing an example of equipment arrangement on one side of a power transmission line in the gas insulated switchgear of FIG. 7. FIG.

[Explanation of symbols]

 1, 11 ... Circuit breaker 2, 12 ... Disconnector 3,13 ... High-speed grounding switch 4,14 ... Line grounding switch 5,15 ... Bushing 6a-6e, 16a-16e ... Insulation spacer 7, 17 ... Connection busbar 8, 18 ... Connection bus for branch circuit 9 ... Mechanical interlock circuit 10, 20 ... Separation device 21 ... Transmission line

Claims (2)

[Claims] 1. A circuit breaker and a disconnector are connected in series to both ends of each power transmission line of the circuit, and a line grounding switch is connected to the power transmission line side of the circuit breaker. In a gas-insulated switchgear in which a high-speed grounding switch is connected between the wire side or a disconnector and a circuit breaker, the high-speed grounding switch is arranged in a branch with respect to the main circuit from the circuit breaker to the transmission line. A gas-insulated switchgear characterized by forming a branch circuit and partitioning the high-speed grounding switch independently of the equipment on the main circuit side. 2. The gas insulated switchgear according to claim 1, wherein a disconnecting device or a disconnector for disconnecting the main circuit and the high-speed grounding switch is provided in the branch circuit.