JPH05260618A - Gas-insulated apparatus - Google Patents

Abstract

PURPOSE:To provide a gas-insulated apparatus with a simple structure that is easy to fabricate and having good mechanical strength and insulating characteristics resistant to a metallic contamination by forming simply a groove or a ring spacer for electric-field relaxation at a coupling flange in a grounded metallic container. CONSTITUTION:A high-voltage conductor 1 is supported and insulated by a conical insulating spacer 10 in a grounded metallic container 11 sealed with an insulating gas 2. A groove 13 is provided for electric-field relaxation between a coupling flange 12 and the surface of the insulating spacer 10. The groove 13 is formed at a contact part among the coupling flange 12, the insulating spacer 10, and the insulating gas 2, i.e., at a part exposed to the insulating gas 2 in the coupling flange 12. In this case, the groove 13 is 3mm to 10mm in width and 3mm to 10mm in depth.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas insulation device using an insulation gas such as SF6 gas as an insulation medium.
In particular, the present invention relates to a gas insulation device in which a connection portion between a grounded metal container in which an insulating gas is sealed and an insulating spacer supporting a high voltage conductor therein is improved.

[0002]

2. Description of the Related Art In a gas insulation device such as a gas insulation switchgear or a gas insulation busbar, a large number of insulation spacers are used for accommodating and housing a high-voltage conductor in a grounded metal container while insulating and supporting it. This insulating spacer is, for example, Japanese Patent Publication No. 54-4.
As disclosed in Japanese Patent No. 4106 and Japanese Patent Laid-Open No. 55-155512, an insulating spacer body made of a thermosetting synthetic resin such as an epoxy resin supports a high-voltage conductor, and a flange of the insulating spacer is filled with a mounting bolt. Is embedded. Furthermore, since the insulation performance of SF6 gas tends to deteriorate due to an unequal electric field, a grounding shield is integrally embedded around the high-voltage conductor as a countermeasure, and its potential is passed through a grounding metal fitting that also serves as a mounting bolt hole. It is normal to secure it.

To explain this point in detail with reference to FIG. 3, in the conventional spacer, the high-voltage conductor 1 is conical-shaped in a grounded metal container 3 in which an insulating gas 2 such as SF6 gas is sealed. The spacers 4 are used to support them in an insulated state. A current-carrying member 41 for joining the high-voltage conductors 1 to each other is integrally cast at the center of the conical insulating spacer 4. In addition, a bolt mounting bracket 6 is integrally cast near the outer peripheral portion of the insulating spacer 4. Furthermore,
A conductive ring 7 that acts as a ground shield is buried inside the insulating spacer 4. The conductive ring 7 is normally grounded, which alleviates the electric field at the joint between the metal container 3 and the insulating spacer 4 and contributes to the improvement of the insulating performance.
Then, the connecting flange 5 provided on the metal container 3 is fastened to the bolt mounting metal fitting 6 for the flange of the insulating spacer 4 with a bolt 8, and a packing 9 such as an O-ring is placed in a packing groove provided on the insulating spacer 4. Connection flange 5
The airtightness is maintained.

[0004]

However, the gas insulating device having such a structure has the following disadvantages due to the structure of the insulating spacer portion.
That is, since it is necessary to cast the conductive ring 7 integrally in the insulating spacer 4, it takes a lot of man-hours at the time of casting, and the structure becomes complicated, resulting in a high cost. Further, it is not preferable to cast the conductive ring 7 made of a small metal ring integrally in the insulating spacer in terms of mechanical characteristics, especially in terms of thermal stress, and cracks may occur in the synthetic resin forming the insulating spacer. It also causes Therefore, the conductive ring 7 that is integrally cast in the insulating spacer 4
Was required to be omitted. Further, it is also known that minute metallic foreign matters exist inside this type of gas insulation device, and they move and disturb the electric field, causing dielectric breakdown. In the conventional gas insulation device, there is no countermeasure against such floating of foreign metal, and some improvement measures have been desired.

The present invention was proposed in order to solve the above-mentioned problems of the prior art. The object of the present invention is that the structure is simple, the manufacture is easy, and the mechanical stress is excellent. Another object of the present invention is to provide a gas insulation device having a preferable structure in terms of insulation performance against foreign metal.

[0006]

In order to achieve such an object, the invention of claim 1 is formed between the connecting flange and the surface of the insulating spacer at the exposed portion of the connecting flange of the grounded metal container to the insulating gas. A groove for relaxing an electric field, for example, a groove formed in a width of 3 to 10 mm and a depth of 3 to 10 mm is provided.

The invention according to claim 2 is characterized in that a ring-shaped spacer for relaxing an electric field is arranged between the connecting flange of the grounded metal container and the surface of the insulating spacer.

[0008]

According to the present invention having the above structure, the electric field in the high electric field portion formed by the insulating spacer and the connecting flange is relaxed by the action of the groove for relaxing the electric field or the ring-shaped spacer, so that the metallic foreign matter Does not disturb the electric field. As a result, the conductive ring 7 embedded inside the insulating spacer becomes unnecessary, and the structure of the insulating spacer can be simplified.

[0009]

Embodiments of the present invention will be described below with reference to FIGS. It should be noted that the same parts as those in the conventional technique of FIG.

(1) First Embodiment FIG. 1 In this first embodiment, the high voltage conductor 1 is made of an insulating gas 2
It is housed in a grounded metal container 11 in which is insulated and supported via a conical insulating spacer 10. That is, the end of the ground metal container 11 has a connecting flange 1 for connecting adjacent ground metal containers 11 to each other.
2 is provided, and the peripheral portion of the insulating spacer 10 is sandwiched between the connecting flanges 12. In addition, a conductive member 41 for joining the insulating spacer 10 and the high-voltage conductor 1 to each other.
Are integrally cast in the center of the conical insulating spacer 10. Connection flange 1 provided on the grounded metal container 11
2, the insulating spacer 10 and the insulating gas 2 are in contact with each other, that is, the connecting flange 12 of the grounded metal container 11.
At the exposed portion of the insulating gas 2 in the connection flange 12
A groove 13 for relaxing an electric field is provided between the insulating spacer 10 and the insulating spacer 10. This groove 13 has a width of 3
It is formed within a range of mm to 10 mm and a depth of 3 mm to 10 mm.

In the insulating spacer 10 having such a structure, since the conductive ring 7 is not embedded as in the conventional case, it is not necessary to cast the insulating spacer 10 together with the support metal fittings of the conductive ring 7. This is useful for improving the spacer manufacturing work and improving the quality, that is, stabilizing the quality. In addition, since the insulating spacer 10 and the connecting flange 12 are separately formed, the manufacturing is very easy, and the both can be integrated by using a mounting bracket and a bolt.

In particular, if the conductive ring 7 is not embedded as in the conventional case, the insulating spacer 10 and the connecting flange 5 are connected.
Although the electric field strength at the end curvature portion in contact with is likely to deteriorate the insulating performance of the insulating spacer 10, in the present embodiment, by providing the groove 13 for relaxing the electric field in the connecting flange 12, it is possible to reduce the conventional electric field. The electric field at the end curvature portion of the coupling flange 12 can be relaxed without providing such a conductive ring. As a result, even if there is a foreign metal inside the grounded metal container, the presence of the groove 13 keeps the electric field at the connecting flange 12 low, so there is no risk of impairing the insulation performance. Therefore, it is possible to provide an insulating spacer that is simple in structure, easy to manufacture, and mechanically preferable. Further, since the groove 13 also functions as a trap for collecting the metallic foreign matter, the movement of the metallic foreign matter is effectively prevented.

(2) Second Embodiment ... FIG. 2 In this second embodiment, a connecting flange 12 is provided at an end of the grounding metal container 11 for connecting adjacent grounding metal containers 11 to each other. A peripheral portion of the insulating spacer 10 is sandwiched between the connecting flanges 12. Further, the current-carrying member 41 for joining the insulating spacer 10 and the high-voltage conductor 1 to each other is integrally cast in the central portion of the conical insulating spacer 10. A ring-shaped spacer 30 for relaxing an electric field is sandwiched between the connecting flange 12 and the convex surface of the conical insulating spacer 10. The ring-shaped spacer 30 has the insulating spacer 10 with the airtight packing fitted in the packing groove 31 provided on the surface thereof.
Along with the peripheral edge portion, it is clamped and clamped by bolts 8 between the connection flanges 12 of the adjacent grounded metal containers 11. Further, the ring-shaped spacer 20 is larger than the inner diameter of the metal container 11 in a range of 2 to 20 mm and has a thickness of 5 to 30.
It is configured within the range of mm. Therefore, also in this second embodiment, the connecting flange 12, the connecting flange 12, is exposed to the insulating gas 2 in the connecting flange 12 of the grounded metal container 11.
A groove 13 for relaxing an electric field is formed between the insulating spacer 10 and the surface of the ring-shaped spacer 30.

Also in the second embodiment having such a configuration, the presence of the ring-shaped spacer causes the connecting flange 1
Since the electric field at the joint between 2 and the insulating spacer 10 is relieved, the effect of relieving the electric field and the effect of preventing the deterioration of the insulation characteristics due to foreign matter are exhibited without providing the conductive ring 7.
In addition, when the ring-shaped spacer 30 is used to form the groove 13 for relaxing the electric field as shown in FIG. 2, the synergistic effect with the existence of the spacer 30 produces a more excellent effect.

(3) Other Embodiments In the above embodiments, only the single-phase insulating spacer has been described, but it goes without saying that the present invention can be applied to a three-phase insulating spacer. In addition, in the second embodiment, especially the groove 13
Even if the ring-shaped spacer for relaxing the electric field is not provided, the same effect as that of the first embodiment can be obtained.

[0016]

As described above, according to the present invention,
By providing a groove for electric field relaxation in the connecting flange portion of the grounded metal container, or by simply providing a ring spacer for electric field relaxation, the structure is simple and the manufacturing is easy,
It is possible to provide a gas insulation device which is excellent in mechanical strength and also prevents deterioration of insulation performance due to foreign metal.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a first embodiment of a gas insulation device of the present invention.

FIG. 2 is a vertical cross-sectional view showing a second embodiment of the gas insulation device of the present invention.

FIG. 3 is a vertical sectional view showing an example of a conventional gas switchgear.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... High-voltage conductor 2 ... Insulation gas 3 ... Metal container 4 ... Insulation spacer 41 ... Conducting member 5 ... Connection flange 6 ... Bolt mounting metal fitting 7 ... Conductive ring 8 ... Bolt 9 ... Packing 10 ... Insulation spacer 11 ... Metal container 12 ... Connection flange 13 ... Groove for electric field relaxation 20 ... Ring spacer for electric field relaxation

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[Procedure amendment]

[Submission date] June 16, 1992

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

Claims (2)

[Claims] 1. A grounded metal container in which an insulating gas is filled, and an insulating spacer for insulating and supporting a high-voltage conductor, wherein a peripheral portion of the insulating spacer is sandwiched between connecting flanges provided in the grounded metal container. In the gas insulating device, the gas insulating device is characterized in that a groove for electric field relaxation formed between the connecting flange and the surface of the insulating spacer is provided in the exposed portion of the connecting flange of the grounded metal container to the insulating gas. .. 2. A grounded metal container filled with an insulating gas, and an insulating spacer for insulating and supporting a high-voltage conductor, wherein a peripheral portion of the insulating spacer is sandwiched between connecting flanges provided on the grounded metal container. In the gas insulating device, the gas insulating device is characterized in that a ring-shaped spacer for relaxing an electric field is arranged between the connecting flange of the grounded metal container and the surface of the insulating spacer.