JPS6260421A - Insulating spacer - 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] [Technical Field of the Invention] The present invention relates to an insulating spacer, and in particular is used in gas insulated switchgear, conduit aerial power transmission equipment, etc. in which an insulating gas such as SF or gas is used as an insulating medium. This invention relates to improvements in insulating spacers.

[Technical background of the invention and its problems]

In gas-insulated switchgear and pipeline aerial power transmission equipment, high-voltage conductors are insulated and supported in a grounded metal container.
Many insulating spacers are used.

This insulating spacer supports a high voltage conductor with an insulating spacer body made of thermosetting synthetic resin such as epoxy resin, as shown in Japanese Patent Publication No. 54-44106 and Japanese Patent Application Laid-open No. 55-155512. A filler metal for the mounting bolt is embedded in the flange. Furthermore, because SF and gas tend to have unequal electric fields and their insulation performance deteriorates, as a countermeasure, a grounding shield is embedded around the high voltage conductor, and this potential is connected to a grounding bracket that also serves as a bolt hole. This is normally secured through the .

As shown in FIG. 4, the conventional insulating spacer stores a high voltage conductor 1 insulated and supported by an insulating spacer 40 in a grounded metal container 3, and insulates an insulating gas 2 such as SF or gas into the metal container 3. is included. The current-carrying member 41 that connects the high voltage conductors 1 to each other is cast integrally with the insulating spacer body 4. Further, the insulating spacer 40 has a metal flange 6 integrally cast on the outer periphery of the flange portion of the insulating spacer main body 4.

Further, a conductive ring 71 integrally cast into the insulating spacer body 4 is embedded therein. This conductive ring 71 is always grounded, reduces the electric field at the joint between the metal container 3 and the insulating spacer 40, and contributes to improving insulation performance. Then, tighten both ends of the stud 8 with nuts 8a like bolts so as to pass through the flange portion of the insulating spacer 40, that is, the metal flange 6, and both connecting flanges 5 to the connecting flange 5 provided on the metal container 3. ,
Further, a packing 31 like a ring is placed in a packing groove provided in the insulating spacer main body 4 to maintain airtightness between the connecting flanges 5.

However, such a conventional insulating spacer 40 has the following disadvantages. That is, it is necessary to integrally cast the conductive ring 71 inside the insulating spacer main body 4, which requires a lot of man-hours during casting, and the structure becomes complicated, resulting in high costs.

Further, integrally casting the conductive ring 71 made of a small metal ring inside the insulating member is not preferable mechanically, especially in terms of thermal stress, and may cause cracks.

Therefore, the conductive ring 71 is integrally cast within the insulating member.
It was requested that it be omitted.

[Purpose of the invention]

The present invention has been made in consideration of the above points, and an object thereof is to provide an insulating spacer that has a simple structure, is easy to manufacture, and has a structure that is favorable in terms of mechanical stress.

[Summary of the invention]

In order to achieve such an object, according to the present invention, a metal ring is formed on the outer periphery of the insulating spacer body to be held by a connecting flange of a grounded metal container, and an electric field is relaxed on the inner peripheral surface of the connecting flange. Due to the arrangement of the parts, the structure is simple and easy to manufacture, and the structure is favorable in terms of mechanical stress.

[Embodiments of the invention]

An embodiment of the insulating spacer of the present invention will be described below with reference to FIG. The same parts and parts having the same functions as those in FIG. 4 are given the same reference numerals. That is, a high voltage conductor 1 is insulated and stored in a grounded metal container 3 filled with an insulating gas 2 via an insulating spacer 40. Usually, a grounded metal container 3 is placed at the end of the metal container 3. A connecting flange 5 is provided for connecting each other. The insulating spacer 40 is sandwiched between the connecting flanges 5 and supports the high voltage conductor 1 within the grounded metal container 3.

The insulating spacer 40 includes the insulating spacer body 4 and the high voltage conductor 1.
The electrically conductive members 41 that connect each other are integrally cast into the insulating spacer main body 4, and the metal flanges 6' which are sandwiched between the connecting flanges 5 and 5 are formed on the outer periphery of the insulating spacer main body 4 so as to be integrated with the insulating spacer main body 4. Inset and formed.

The metal flange 6 is passed through the connecting flange 5 by a stud 8, and both ends of the stud 8 are tightened by nuts 8a. Further, the insulating spacer main body 4 is fastened to both connecting flanges 5 through a packing 31 such as an O-ring placed in a packing groove so as to maintain airtightness.

Further, a metal ring 7 is provided on the inner peripheral surfaces of the connecting flanges 5 that sandwich the insulating spacer 40, thereby forming an electric field relaxation part 10.

In the insulating spacer 40 configured in this way, since the conductive ring, that is, the grounding shield is not embedded as in the conventional case, there is no need to cast the grounding shield together with the supporting metal fittings, which improves the manufacturing work of the insulating spacer. and quality improvement, that is, quality stabilization. Further, since the insulating spacer main body 4 and the metal flange 6 can be made separately, manufacturing becomes very easy, and the two can be integrated by using a fastener and a bolt. Here, unlike the conventional structure, a conductive ring is not embedded, so the electric field strength at the end curvature of the part where the insulating spacer main body 4 and the connecting flange 5 contact is simply high in the conventional connecting flange 5 structure, There was a risk that the insulation performance of the spacer 40 would be impaired. However, by providing the metal ring 7 to form the electric field relaxation part 10 as in the present invention, even with the conventional structure of the connecting flange 5, it is possible to relieve the electric field at the curved end portion with the insulating spacer body 4. can. In this way, the metal ring 7 has the same effect of mitigating the electric field as the conductive material conventionally embedded in the insulating spacer body 4, so that the electrical performance can be maintained without impairing the mechanical performance as in the conventional case.

In the above embodiment, only a single-phase insulating spacer was described, but it goes without saying that the present invention can also be applied to a three-phase insulating spacer.

Next, a first alternative embodiment of the present invention will be described with reference to FIG. The same parts or parts having the same functions as those in FIG. 1 are given the same reference numerals. That is, the grounded metal container 3
A convex portion 51 of the connecting flange formed to have a curvature protruding inward from the metal container 3 is provided on the inner peripheral surface of the connecting flange 5 that connects each other, and a gap 52 is provided on the side of the connecting flange that contacts the insulating spacer body 4. The electric field relaxation part 10 is formed by providing the electric field relaxation part 10.

With this configuration, the electric field on the inner peripheral surface of the connecting flange 5 can be alleviated without particularly providing a metal ring, and the structure is simple, easy to manufacture, and mechanically preferable insulation. Spacers can be provided.

Next, a second alternative embodiment of the present invention will be described with reference to FIG. The same parts or parts having the same functions as those in FIG. 1 are given the same reference numerals. That is, the insulating spacer 40
is the insulating spacer body 4. It has a current-carrying member 41 that connects the high voltage conductors 1 to each other, and is configured such that a metal flange 6 is fitted onto the outer periphery of the insulating spacer body 4. The metal flange 6 of the insulating spacer 40 is sandwiched between the connecting flanges 5, passes through the stud 8, and is attached by tightening both ends with nuts 8a. Airtightness is maintained through a packing 31 such as an O-ring. Furthermore, the joint surface of the metal flange 6 that is joined to the insulating spacer main body 4 is connected to the connecting flange 5 that holds the metal flange 6.
It is in contact with the end of the curved portion of the end facing the insulating spacer main body 4. The thickness of the metal flange 6 in the axial direction is larger than the thickness of the insulating spacer body 4.

Then, the joint surface of the metal flange 6 with the insulating spacer main body 4 is formed to have approximately the same dimension as the inner peripheral diameter of the metal container 3, thereby forming the electric field relaxation part 10.

Since the insulating spacer 40 constructed in this manner does not have a conductive ring buried therein as in the conventional case, the advantages thereof are the same as in the embodiments of the present invention. In addition, since the joint surface of the metal flange 6 with the insulating spacer body 4 is formed to have approximately the same dimension as the inner diameter of the metal container 3, even with the conventional structure of the connecting flange 5, the end curvature with the insulating spacer body 4 is The electric field in the area can be relaxed. Therefore, since it has the same effect as the conductive ring embedded in the insulating spacer main body 4, the electrical performance can be maintained without embedding the conductive ring and therefore without impairing the mechanical performance.

In addition, in the above-mentioned first and second other embodiments, only a single-phase insulating spacer was described, but it goes without saying that the present invention can also be applied to a three-phase insulating spacer.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to provide an insulating spacer that has a simple structure, is easy to manufacture, and has excellent mechanical strength.

[Brief explanation of the drawing]

FIG. 1 is a vertical cross-sectional view of an insulating spacer of the present invention, FIG. 2 is a vertical cross-sectional view of a first other embodiment of the present invention, and FIG. 3 is a vertical cross-sectional view of a second embodiment of the present invention. FIG. 4 is a longitudinal sectional view of a conventional insulating spacer. DESCRIPTION OF SYMBOLS 1...High voltage conductor, 2...Insulating gas, 3...Metal container, 4...Insulating spacer body, 5...Connection flange, 6...Metal flange, 7...Metal ring . 8... Stud, 8a... Nut, 1o... Electric field relaxation part, 31... Packing, 40... Insulating spacer. 41... Current-carrying member, 51... Convex portion of connecting flange,
52... Gap.

Claims (6)

[Claims] (1) An insulating spacer body that insulates and supports a high voltage conductor;
This insulating spacer is formed by separately forming the insulating spacer main body and a metal flange that is attached between the connecting flanges of the grounded metal containers, characterized in that an electric field relaxation part is provided on the inner circumferential surface of the connecting flanges of the metal containers. Insulating spacer. (2) The insulating spacer according to claim 1, wherein the electric field relaxation portion is formed by attaching a metal ring to the inner peripheral surface of the connecting flange. (3) The electric field relaxation part is formed so that the inner circumferential surface of the connecting flange has a convex shape protruding from the inner circumferential surface of the metal container, the tip of this convex shape has a curvature, and there is a gap on the insulating spacer main body side. An insulating spacer according to claim 1. (4) The insulating spacer according to claim 1, wherein the electric field relaxation portion is formed such that a curved portion of the end of the connecting flange of the metal container with respect to the insulating spacer body is in contact with the metal flange joint surface. (5) The insulating spacer according to claim 1, wherein the electric field relaxation part is formed so that the thickness of the metal flange in the axial direction is larger than the thickness of the insulating spacer main body. (6) The insulating spacer according to claim 1, wherein the insulating spacer body and the connecting flange are formed so as to maintain airtightness through packing.