JP2000069631A - Gas-insulated electrical apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas-insulated electrical apparatus with can maintain its internal pressure in a safe state without discharging the internal gas into the atmosphere, even if the internal gas pressure is elevated by an insulation breakdown, etc., and is compact in size and highly safe from an environmental point of view. SOLUTION: A gas-insulated transformer 3 is composed of a grounding metal chamber 1 in which SF6 gas is sealed with a pressure not lower than the atmospheric pressure, and a transformer main part 2 including windings which is housed in the grounding metal chamber 1. A gas discharge valve 4 is attached to the grounding metal chamber 1. An airtight gas sealing bag 7, in which nitrogen gas is sealed, is provided inside the grounding metal chamber 1 and attached to the suction inlet 5 of the discharge valve 4. The pressure of the nitrogen gas in the gas sealing bag 7 and the pressure of the SF6 gas in the grounding metal chamber 1 are balanced with each other. The discharge valve 4 is controlled so as to be opened, when the gas pressure in the ground metal chamber 1 exceeds a discharge start pressure, and closed when the pressure is lowered down to a discharge stop pressure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-insulated electric device using an insulating gas as an insulating medium, and more particularly to a gas-insulated electric device in which the influence of an insulating gas or its decomposition gas on the environment is improved. About.

[0002]

2. Description of the Related Art In transformers and other transmission and transformation equipment,
As an insulating medium, sulfur hexafluoride gas (hereinafter referred to as "SF6 gas")
) Are often used. This SF
6 Gas is a gas in which fluorine ions, which are halogen elements, are covalently bonded to sulfur ions having hexavalent electron pairs without any excess or shortage, and have extremely high chemical stability and little ionization (ionization) phenomenon. It is a gas having excellent so-called electrical insulation properties. Under these circumstances, SF6 gas is now widely used as an insulating medium, mainly in power transmission and transformation equipment.

As described above, in a gas-insulated electric device using SF6 gas as an insulating medium, if insulation breakdown occurs inside the device, the SF6 gas is heated and decomposed, so that the gas pressure inside increases sharply, and It causes deformation and breakage. In order to deal with this, conventionally, the pressure inside the equipment has increased sharply by giving a margin to the pressure resistance of the container in advance, or by attaching a pressure relief valve to the container to release SF6 gas and its decomposition gas into the atmosphere. Was prevented from doing so.

However, SF6 gas generates decomposition gases such as hydrogen fluoride gas, sulfur tetrafluoride gas and sulfur dioxide gas by arc discharge and partial discharge. Is not desirable to be released into the atmosphere. For this reason, JP-A-58-63909, JP-A-58-63010, and JP-A-8-214.
Japanese Patent Publication No. 418 proposes a technique in which a buffer tank for storing released gas is installed at a gas discharge port of a pressure release valve of a gas-insulated electric device to prevent SF6 gas and its decomposition gas from being released into the atmosphere. Have been.

[0005]

However, in a gas-insulated electric device in which a buffer tank is installed at a gas discharge port of a pressure-releasing valve as described above, gas pressurized to a pressure higher than the atmospheric pressure in the gas-insulated electric device is used. Flows into the buffer tank at about atmospheric pressure. Therefore, in order to prevent the internal pressure of the buffer tank from suddenly increasing and damaging the buffer tank, it is necessary to make the tank volume sufficiently large with respect to the amount of released gas. However, enlarging the buffer tank in this way has been disadvantageous for downsizing the gas-insulated electric equipment.

[0006] Conventionally, gas-insulated electrical equipment SF
The release of 6 gas and its decomposition gas to the atmosphere has been problematic from the viewpoint that SF6 gas is expensive gas and decomposition gas is harmful to the human body. Although it is small, it is also a problem from the viewpoint of the effect on global warming. From such multiple viewpoints, it is necessary to minimize the emission of gas into the atmosphere. This is because SF6 gas is used to reduce the amount of SF6 gas used.
The same applies to the case of a gas insulated switchgear using a mixed gas of gas and nitrogen gas.

[0007] The present invention has been proposed to solve the above-mentioned problems of the prior art.
Even if the internal gas pressure increases due to insulation breakdown, etc., the internal pressure of the equipment can be maintained in a safe state without releasing the internal gas to the atmosphere, and compact and highly environmentally safe gas-insulated electrical equipment Is to provide.

[0008]

In order to achieve the above object, the present invention relates to a gas-insulated electric device in which an electric device is housed in a container filled with an insulating gas. Having.

That is, the invention according to claim 1 is characterized in that a gas release valve for adjusting the internal gas pressure of the container is provided, and a gas bag filled with gas is attached to the gas release valve. Features. According to the first aspect of the present invention, when the insulating gas is heated and decomposed due to a short circuit accident of the gas insulated electric equipment and the gas pressure in the container increases, the gas in the gas bag is increased by the gas release valve. To the atmosphere. Then, the internal pressure of the container is reduced, so that the device is prevented from being damaged and the insulating gas in the container can be prevented from being released into the atmosphere.

According to a second aspect of the present invention, in the gas insulated electric device according to the first aspect, the gas pressure relief valve is mounted on a pressure relief tank separate from the container, and the container and the pressure relief tank are connected to each other. , And are connected by a gas pipe. According to the second aspect of the present invention,
By separating the container of the device main body and the pressure release tank, the pressure release tank can be installed at an arbitrary location, and the space occupied by the device can be effectively used.

According to a third aspect of the present invention, in the gas insulated electric device according to the first or second aspect, the container includes:
A plurality of gas sections are provided, and the pressure relief tank is provided for each gas section. In the invention according to claim 3 described above, when a decomposed gas is generated due to a short circuit or the like, the decomposed gas is present only in the gas section in which the accident has occurred and the pressure relief tank connected thereto, Processing of cracked gas and recovery of SF6 gas are facilitated.

According to a fourth aspect of the present invention, in the gas insulated electric device according to the first or second aspect, the container includes:
A plurality of gas sections are provided, and the pressure relief tank is provided for each gas section having the same gas pressure. In the fourth aspect of the present invention, by sharing the pressure relief tank, the required number of pressure relief tanks is reduced, so that the economy can be improved.

According to a fifth aspect of the present invention, in the gas insulated electric device according to any one of the second to fourth aspects, a check valve is attached to the gas pipe. According to the fifth aspect of the present invention, the check valve prevents the cracked gas flowing into the pressure relief tank from the gas section where the accident has occurred from flowing into another sound gas section.

According to a sixth aspect of the present invention, in the gas insulated electric device according to any one of the first to fifth aspects, air is used as a gas filled in the gas bag. According to the sixth aspect of the present invention, by using air as the gas in the gas bag, manufacturing costs can be reduced.

According to a seventh aspect of the present invention, a gas release valve for adjusting an internal gas pressure is provided at a gas discharge port of the container, and a gas bag filled with gas is attached to the gas release valve. It is characterized by having. In the invention according to claim 7 described above, when the insulating gas is decomposed due to a short circuit accident of the gas insulated electric equipment and the gas pressure in the container increases and the pressure relief valve operates, the released gas is supplied to the pressure relief valve. Stored in the attached bag. Therefore, release of the insulating gas and its decomposition gas to the atmosphere can be prevented. In addition, during normal operation, the volume occupied by the gas bag can be reduced by degassing the sealed gas bag, so that the equipment can be made compact.

The invention according to claim 8 is characterized in that the container is provided with a plurality of gas sections, and the gas sections having the same gas pressure are connected by a gas pipe. In the invention according to claim 8 described above, when an accident occurs in a certain gas section and the gas pressure rises, the accident section and the other sound sections connected by the gas pipes include:
The increase in gas pressure can be shared. For this reason, the pressure rise in the accident category can be reduced as compared with the case where the connection is not made by the gas pipe.

According to a ninth aspect of the present invention, in the gas insulated electric device according to the eighth aspect, a cylinder and a piston that can reciprocate in the cylinder are attached to the gas pipe. According to the invention of claim 9 described above, the gas pressure that increases in the gas section where the accident has occurred can be transmitted to other gas sections by moving the piston through the cylinder. Significant increase is suppressed. Further, the decomposition gas in the gas section where the accident has occurred can be prevented from flowing into another gas section.

According to a tenth aspect of the present invention, in the gas insulated electric device according to any one of the first to ninth aspects, the insulating gas is SF6 gas. In the invention according to claim 10 as described above, while using SF6 gas having excellent electrical insulation properties, while maintaining excellent performance,
The emission to the atmosphere can be prevented.

According to an eleventh aspect of the present invention, in the gas insulated electric device according to any one of the first to ninth aspects, the insulating gas is a mixed gas of SF6 gas and nitrogen gas. And According to the eleventh aspect of the present invention, environmental harmony can be realized by reducing the amount of SF6 gas used.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (1) First Embodiment (Structure) One embodiment corresponding to the invention described in claims 1 and 10 will be described below with reference to FIG.
FIG. 1 is a structural diagram of the gas insulated transformer of the present embodiment. That is, the gas insulating transformer 3 is constructed by housing the main body 2 including the winding of the transformer in the grounded metal container 1 in which SF6 gas is sealed at a pressure higher than the atmospheric pressure. A gas release valve 4 is attached to the grounded metal container 1. Reference numeral 5 denotes a suction port of the gas release valve 4, and reference numeral 6 denotes a discharge port of the gas release valve 4. Further, an airtight gas sealing bag 7 in which nitrogen gas is sealed is attached to the suction port 5 of the gas release valve 4 in the grounded metal container 1.

The nitrogen gas in the gas filling bag 7 is in pressure equilibrium with the SF 6 gas in the grounded metal container 1. When the gas pressure in the grounded metal container 1 exceeds the pressure release start pressure set to the normal operation gas pressure or more, the gas release valve 4
Open the gas release valve 4 to release gas into the atmosphere,
When the gas pressure in the grounded metal container 1 drops to the pressure release stop pressure set to be equal to or lower than the normal operation gas pressure, the gas release valve 4
Is closed so that gas emission is stopped.

(Operation) The operation of the present embodiment having the above configuration is as follows. That is, when insulation breakdown occurs in the grounded metal container 1 due to a short circuit accident of the gas insulating transformer 3 or the like, the S sealed in the grounded metal container 1
As the F6 gas is heated and decomposed, the gas pressure in the grounded metal container 1 increases beyond the gas pressure during normal operation, and pressurizes the gas filling bag 7. And the nitrogen gas pressure of the gas filling bag 7 becomes
When the pressure exceeds the release pressure of the gas release valve 4, the gas release valve 4
Is opened, and the nitrogen gas in the gas sealing bag 7 is released into the atmosphere.
Then, the gas sealing bag 7 is deflated and the volume of the gas sealing bag 7 occupying the grounded metal container 1 is reduced, so that the gas pressure in the grounded metal container 1 is reduced. Further, when the gas pressure in the grounded metal container 1 falls below the pressure at which the gas release valve 4 stops releasing the pressure, the valve of the gas release valve 4 closes and the release of nitrogen gas stops.

(Effect) According to the present embodiment as described above, the release of nitrogen gas in the gas sealing bag 7 causes
The gas pressure in the grounded metal container 1 can be maintained at a safe pressure equal to or lower than the normal operating pressure without releasing the gas and its decomposition gas to the atmosphere.

Further, the nitrogen gas released when the gas release valve 4 is operated has no toxicity like the decomposition gas of SF6 gas and does not affect the global environment like SF6 gas. Equipment with high environmental safety can be obtained.

Further, during normal operation, the gas filled bag 7
Since the pressure of nitrogen gas in the inside is the same as the pressure of SF6 gas in the grounded metal container 1, the sealed volume of nitrogen gas is smaller than under atmospheric pressure, and a buffer tank is attached to the gas discharge port of the grounded metal container 1. Thus, the size of the device can be reduced as compared with a method of preventing the release of the internal insulating gas into the atmosphere.

(2) Second Embodiment (Structure) One embodiment corresponding to the second and tenth aspects of the present invention will be described below with reference to FIG.
FIG. 2 is a structural diagram of the gas insulated transformer of the present embodiment. That is, in the present embodiment, the main body 2 of the transformer is housed in the grounded metal container 1, and the gas sealing bag 4 is housed in the pressure relief tank 8 separate from the grounded metal container 1. A gas pressure relief valve 9 is attached to the pressure relief tank 8. Reference numeral 10 denotes a suction port of the gas release valve, and reference numeral 11 denotes a discharge port of the gas release valve 9. An airtight gas sealing bag 12 in which nitrogen gas is sealed is attached to the suction port 10 of the gas pressure relief valve 9 in the pressure relief tank 8. Further, the ground metal container 1 and the tank 8 are connected by a gas pipe 13.

The gas release valve 9 opens the gas release valve 9 to release gas into the atmosphere when the gas pressure in the release tank 8 exceeds the release pressure set at a level higher than the normal operating gas pressure. Thereafter, when the gas pressure in the pressure release tank 8 decreases to a pressure release stop pressure set to be equal to or lower than the normal operation gas pressure, the gas release pressure valve 9 is closed and the gas release is stopped. The other members have the same configuration as in the first embodiment.

(Operation) The operation of the present embodiment having the above configuration is as follows. That is, when a short circuit accident or the like of the gas insulated transformer 3 occurs, the grounded metal container 1
The SF6 gas inside is heated and decomposed to increase the gas pressure.
The gas pressure is applied to the pressure release tank 8 via the gas pipe 13, and the gas sealing bag 12 is pressurized. When the gas pressure exceeds the pressure release start pressure of the gas release valve 9, nitrogen gas is released into the atmosphere. When the internal pressure of the pressure release tank 8 decreases due to the release of the nitrogen gas, the internal pressure of the grounded metal container 1 also decreases via the pipe 13. When the internal pressure of the pressure release tank 8 drops below the pressure stop pressure of the gas pressure relief valve 9, the gas pressure relief valve 9 closes and the release of nitrogen gas stops.

(Effect) According to the present embodiment as described above, similarly to the first embodiment, even when the internal gas pressure increases due to the occurrence of an accident in the gas electric equipment, the SF6 gas or The gas pressure in the grounded metal container 1 can be reduced to a safe pressure without releasing the decomposition gas into the atmosphere, and the grounded metal container 1 can be prevented from being broken.

In this embodiment, the grounded metal container 1 of the gas insulated transformer 3 and the pressure relief tank 8 are connected to the gas pipe 13.
, The pressure relief tank 8 can be installed at an arbitrary location, and the installation space can be efficiently utilized.

Furthermore, the shape of the pressure relief tank 8 may be any shape as long as it can satisfy the predetermined internal volume and can be arbitrarily designed, so that the space occupied by the equipment can be effectively used and a compact gas insulated electric equipment can be obtained.

(3) Third Embodiment (Structure) One embodiment corresponding to the third and tenth aspects of the present invention will be described below with reference to FIG.
FIG. 3 is a structural diagram of the gas-insulated electric device of the present embodiment. That is, in the present embodiment, the grounded metal container 13 is connected to the grounded metal container 16 of the gas insulated switchgear. The main body 17 of the transformer is housed in the grounded metal container 16, and the bus 14 is housed in the grounded metal container 16. Ground metal container 13 and ground metal container 1
6 is divided by an insulating spacer 18. The main body 17 and the bus 14 are connected to each other through a conductor 19 and a conductor 19 mounted on an insulating spacer 19.

The pressure release tanks 21a, 21
b are provided and connected to grounded metal containers 13 and 16 via gas pipes 22a and 22b, respectively. As in the second embodiment, gas release valves 23a and 23b and gas suction ports 24a and 2b are provided in the pressure release tanks 21a and 21b.
4b, gas outlets 25a, 25b, gas filled bags 26a,
26b is provided. Other configurations are similar to those of the second
This is the same as the embodiment.

(Operation) The operation of the present embodiment having the above-described configuration is as follows. That is, for example, when a decomposition gas of SF6 gas is generated due to a short circuit accident or the like in the gas section of the grounded metal container 16, the gas pressure increases. The gas pressure is applied to the pressure release tank 21b via the gas pipe 22b, and the gas sealing bag 26b is pressurized. When the gas pressure exceeds the pressure release start pressure of the gas pressure release valve 23b, nitrogen gas is released into the atmosphere. When the internal pressure of the pressure release tank 21b decreases due to the release of the nitrogen gas, the gas pressure relief valve 2
3b is closed, and the release of nitrogen gas stops. Further, when a short circuit accident or the like occurs in the gas section of the grounded metal container 13, the gas pressure relief valve 23a of the pressure relief tank 21a,
The pressure is reduced by the gas sealing bag 26a.

(Effect) According to the present embodiment as described above, similarly to the second embodiment, SF6 and its decomposed gas are not released to the atmosphere, and the gas pressure in the equipment container is reduced to a safe pressure. Can be lowered to prevent destruction of the container.

Furthermore, since the cracked gas exists only in the gas section where the accident occurred and the pressure relief tank connected to it,
Cracked gas does not flow into the healthy gas compartment, and processing of cracked gas and recovery of SF6 gas after an accident
Only the accident classification needs to be performed, and the gas treatment and recovery work can be performed efficiently.

(4) Fourth Embodiment (Structure) One embodiment corresponding to the invention described in claims 4, 5, and 10 will be described below with reference to FIG. FIG. 4 is a structural diagram of the gas-insulated electric device of the present embodiment. In the present embodiment, when there are a plurality of gas sections as in the third embodiment, instead of separately installing a pressure relief tank for each gas section, a gas section having the same gas pressure is used. The pressure relief tank is shared. That is, one ends of the gas pipes 32a and 32b are connected to the grounded metal container 16 and the grounded metal container 13 similar to those of the third embodiment, respectively. Gas piping 32
The other ends of a and 32b are connected to the same pressure relief tank 27. The gas piping 32a, 32b has a pressure release tank 27
Check valves 33a and 33b for preventing gas from flowing in the direction of the ground metal container 16 and the ground metal container 13 from above. Other configurations are the same as those in the third embodiment.

(Operation) The operation of the present embodiment having the above configuration is as follows. That is, when a short circuit accident or the like occurs, the SF6 gas is heated and decomposed, and the gas pressure in the grounded metal container 16 increases. At this time, since the grounded metal container 16 is connected to the pressure release tank 27 via the pipe 32a, the internal pressure of the pressure release tank 27 also increases, and the pressure in the gas sealing bag 31 increases. When the internal pressure of the gas sealing bag 31 rises to the pressure at which the gas release valve 28 starts releasing pressure, the gas release valve 28 opens, nitrogen gas is released from the gas sealing bag 31 into the atmosphere, and the internal pressure of the pressure release tank 27 decreases. . Further, the internal pressure of the grounded metal container 16 also decreases through the pipe 32a. When the internal pressure of the pressure release tank 27 decreases to the pressure stop pressure of the gas pressure relief valve 28, the gas pressure relief valve 28 closes and the release of nitrogen gas stops.

On the other hand, for the sound gas insulated switchgear side, a gas check valve 33b is installed in the pipe 32b connecting the grounded metal container 13 and the pressure relief tank 27, so that the pressure relief tank Grounding metal container 1 even if internal pressure rises
No SF6 gas containing a decomposition gas flows into 3.

(Effect) According to the present embodiment as described above, even in the event of an accident, the gas pressure in the container can be maintained at a safe pressure, and the check valves 33a, 33
With b, it is possible to prevent the flow of the decomposed gas or the like into the sound gas section, so that safer operation becomes possible.

The grounded metal container 16 and the grounded metal container 1
3 has a structure in which the pressure relief tank 27 is shared, so that the number of pressure relief tanks can be reduced as compared with the case where all separate pressure relief tanks are attached to each gas section, and the economy is improved. At the same time, the equipment can be made more compact.

(5) Fifth Embodiment One embodiment corresponding to the invention described in claims 6 and 10 will be described. That is, the present embodiment is different from the first to fourth embodiments in that the gas-filled bags 7, 12,
Air is used instead of nitrogen gas as the gas to be filled in 26a, 26b, 31. According to this embodiment, even if air is released, there is no problem in terms of environmental safety as in the case of nitrogen gas, and as in the first to fourth embodiments,
The effect of preventing SF6 and its decomposition gas from being released into the atmosphere can be obtained, and the device can be manufactured at lower cost.

(6) Sixth Embodiment (Structure) One embodiment corresponding to the inventions of claims 7 and 10 will be described below with reference to FIG.
FIG. 5 is a structural diagram of the gas insulated transformer of the present embodiment. That is, in the present embodiment, the suction port 5 of the gas release valve 4 in the grounded metal container 1 in the first embodiment is
Instead of attaching the nitrogen gas bag 7, a gas bag 34 for storing the released gas is attached to the gas discharge port 6. The other members have the same configuration as in the first embodiment.

(Operation) The operation of the present embodiment having the above configuration is as follows. That is, when insulation breakdown occurs in the grounded metal container 1 due to a short circuit accident of the gas insulating transformer 3 or the like, the S sealed in the grounded metal container 1
As the F6 gas is heated and decomposed, the gas pressure in the grounded metal container 1 increases beyond the gas pressure during normal operation. Then
Since the gas release valve 4 is opened and the gas from the grounded metal container 1 is stored in the gas bag 34, the gas pressure in the grounded metal container 1 decreases. Further, when the gas pressure in the grounded metal container 1 falls to or below the pressure stop pressure of the gas release valve 4, the valve of the gas release valve 4 closes and the release of gas stops.

(Effects) According to the present embodiment as described above, the gas pressure in the grounded metal container 1 is reduced by the gas bag 34 without releasing the SF 6 gas or its decomposed gas into the atmosphere. The following safe pressure can be maintained.

When the gas bag 34 is attached to the gas discharge port 6 of the gas release valve 4, the gas bag 34 is evacuated in advance so that the volume occupied by the gas bag 34 during normal operation is small. Therefore, the size of the device can be reduced as compared with a case where a buffer tank for storing the released gas is attached to the gas discharge port.

Further, a gas bag 34 containing the released gas 34
Can be easily moved by removing it from the gas release valve 4, so that the gas recovery processing and the like conventionally performed around the gas-insulated electric equipment can be performed at an arbitrary place. And other work safety can be improved.

(7) Seventh Embodiment (Structure) One embodiment corresponding to the eighth and tenth aspects of the present invention will be described below with reference to FIG.
FIG. 6 is a structural diagram of the gas-insulated electric device of the present embodiment. That is, in the present embodiment, similarly to the third embodiment, the grounded metal container 13 and the grounded metal container 16
When a plurality of gas sections are formed by the insulating spacer 18 or the like, each gas section is connected by a gas pipe 35. Other members are the same as in the third embodiment.

(Operation) The operation of the present embodiment having the above configuration is as follows. That is, when a short circuit accident or the like occurs in the gas insulating transformer 15, the SF6 gas is heated and decomposed, and the gas pressure in the grounded metal container 16 increases. The grounded metal container 16 is connected to the grounded metal container 13 of the gas insulated switchgear via a gas pipe 35, and the increase in gas pressure is controlled by the grounded metal container 16 and the grounded metal container 13
And the ground metal container 16 in which the accident occurred.
Can be reduced.

For example, when the volume of the grounded metal container 13 is V1,
When the volume of the grounded metal container 16 is V2, the gas pressure of the grounded metal container 13 during normal operation, and the gas pressure of the grounded metal container 16 are both Po, and the grounded metal container 13 and the grounded metal container 16 are not connected by the pipe 35 Assume that a breakdown occurs in the grounded metal container 16 and the pressure in the grounded metal container 16 increases by dP.

Then, if the grounded metal container 13 and the grounded metal container 16 are connected by the pipe 35, the pressure increase in the grounded metal container 13 and the grounded metal container 16 will be expressed by the following equation (1). The pressure rise is reduced as compared with the case where the ground metal container 13 and the ground metal container 16 are not connected by the pipe 35.

[0052]

V2 / (V1 + V2) × dP (<dP) Expression 1

(Effects) According to the present embodiment as described above, the deformation and breakage of the container of the electric equipment due to the rise of the internal gas pressure at the time of the accident hardly occurs, the reliability of the equipment is improved, and the insulation medium is used. It is possible to obtain a device having a high level of environmental safety and a low risk that certain SF6 gas or its decomposition gas is scattered from the container into the atmosphere.

Further, the present embodiment can be easily realized by connecting gas sections with gas pipes 35 in a conventional gas insulated electric device, so that an inexpensive and compact gas insulated electric device can be constructed. .

(8) Eighth Embodiment (Configuration) One embodiment corresponding to the ninth aspect of the present invention will be described below with reference to FIG. FIG. 7 is a structural view of the gas-insulated electric device of the present embodiment. That is, in the present embodiment, in the seventh embodiment, a cylinder 36 and a piston 37 that can reciprocate in the cylinder 36 are installed in the gas pipe 35 that connects the grounded metal container 16 and the grounded metal container 13. Things. Other members are the same as in the seventh embodiment.

(Operation) The operation of the present embodiment having the above configuration is as follows. That is, when a short circuit accident or the like occurs in the gas insulating transformer 15, the SF6 gas is heated and decomposed, and the gas pressure in the grounded metal container 16 increases. Since the grounded metal container 16 is connected to the grounded metal container 13 of the gas insulated switchgear through the gas pipe 35, the movement of the piston 37 in the cylinder 36 installed in the gas pipe 35 increases the gas pressure. It is transmitted from the grounded metal container 16 to the grounded metal container 13. Therefore, as in the case of the seventh embodiment, the increase in the gas pressure is shared between the grounded metal container 16 and the grounded metal container 13, and the rise in the pressure of the grounded metal container 16 is reduced.

(Effect) According to the present embodiment as described above, the same effect as that of the seventh embodiment can be obtained, and the decomposition gas of SF 6 in the grounded metal container 16 is directly grounded by the piston 37. Since the gas can be confined in the grounded metal container 16 without flowing into the metal container 13, the processing of the decomposition gas and the recovery of SF6 gas need only be performed for the accident category, and the gas processing and the recovery work can be performed efficiently. Can do well.

(9) Other Embodiments The present invention is not limited to the above embodiments, and the size, number, type, etc. of each member can be changed as appropriate. For example, in all of the above embodiments, gas-insulated electrical equipment using SF6 gas as an insulating medium, but as an embodiment corresponding to the invention of claim 11, a mixed gas of SF6 gas and nitrogen gas is used. Alternatively, it can be configured as a gas-insulated electric device using an insulating medium containing no SF6 gas. With this configuration, the same operation and effect as those of the first to eighth embodiments can be obtained, and the SF6
Since the amount of gas used can be reduced, it is possible to obtain a gas-insulated electric device with even higher environmental safety.

[0059]

As described above, according to the present invention,
Even if the internal gas pressure increases due to insulation breakdown, etc., the internal pressure of the equipment can be maintained in a safe state without releasing the internal gas to the atmosphere, and compact and highly environmentally safe gas-insulated electrical equipment Can be provided.

[Brief description of the drawings]

FIG. 1 is a structural diagram showing a gas-insulated electric device according to a first embodiment of the present invention.

FIG. 2 is a structural diagram showing a gas-insulated electric device according to a second embodiment of the present invention.

FIG. 3 is a structural diagram showing a gas-insulated electric device according to a third embodiment of the present invention.

FIG. 4 is a structural diagram showing a gas-insulated electric device according to a fourth embodiment of the present invention.

FIG. 5 is a structural diagram showing a gas-insulated electric device according to a sixth embodiment of the present invention.

FIG. 6 is a structural diagram illustrating a gas-insulated electric device according to a seventh embodiment of the present invention.

FIG. 7 is a structural diagram showing a gas-insulated electric device according to an eighth embodiment of the present invention.

[Explanation of symbols]

 3, 15 ... gas insulating transformer 4, 9, 23a, 23b, 28 ... gas release valve 7, 12, 26a, 26b, 31 ... gas filled bag 8, 21a, 21b, 27 ... release tank 18 ... insulating spacer 34 ... gas bag 36 ... cylinder 37 ... piston

Claims (11)

[Claims] 1. A gas-insulated electric device containing an electric device in a container filled with an insulating gas, wherein a gas release valve for adjusting an internal gas pressure of the container is provided. A gas-insulated electric device, wherein a gas bag in which is sealed is attached. 2. The gas pressure relief valve is mounted on a pressure relief tank separate from the container, and the container and the pressure relief tank are connected by a gas pipe. Gas-insulated electrical equipment. 3. The gas-insulated electric device according to claim 1, wherein the container is provided with a plurality of gas sections, and the pressure relief tank is provided for each gas section. machine. 4. The container according to claim 1, wherein a plurality of gas sections are provided, and the pressure relief tank is provided for each gas section having the same gas pressure. A gas-insulated electrical device as described. 5. The gas insulated electric device according to claim 2, wherein a check valve is attached to the gas pipe. 6. The gas-insulated electric device according to claim 1, wherein air is used as a gas filled in the gas bag. 7. A gas-insulated electric device in which an electric device is housed in a container filled with an insulating gas, wherein a gas discharge valve for adjusting an internal gas pressure is provided at a gas discharge port of the container. A gas-insulated electric device characterized in that a gas bag filled with gas is attached to a pressure relief valve. 8. A gas-insulated electric device in which an electric device is housed in a container filled with an insulating gas, wherein the container is provided with a plurality of gas sections, and a space between the gas sections having the same gas pressure is provided. Gas insulated electric equipment characterized by being connected by gas piping. 9. The gas-insulated electric device according to claim 8, wherein a cylinder and a piston that can reciprocate in the cylinder are attached to the gas pipe. 10. The gas insulated electric device according to claim 1, wherein the insulating gas is SF6 gas. 11. The gas according to claim 1, wherein the insulating gas is a mixed gas of SF6 gas and nitrogen gas.
The gas-insulated electric device according to any one of the above.