JPH08149630A - Conductor support device - Google Patents

Abstract

PURPOSE: To prevent cracking of the end section of the through hole of an insulating space on a recessed section side and, at the same time, to prevent flashover accidents by increasing the withstand voltage of the spacer. CONSTITUTION: A conductor supporting device is provided with an insulating spacer 1 which is put between the flanges of the two tubular bodies of a gas- insulated switchgear, a plurality of recessed sections 3 formed on the spacer 1, conductors 8 respectively buried in the sections 3 after the conductors 8 are passed through through holes 5 at the central part of the sections 3, and a cylindrical gap 11 which is separated from the peripheral surface of the end sections of the holes 5 having a prescribed length on the sections 3 side and the peripheral surface of the conductors at the same interval.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a conductor supporting device for supporting a conductor by an insulating spacer interposed between two flanges of two pipes of a gas insulated switchgear in the field of electric power distribution.

[0002]

2. Description of the Related Art A conventional conductor supporting device of this kind has a structure shown in FIGS. 3 to 5, for example. In these figures, 1 is an insulating spacer made of epoxy resin,
It is interposed between both flanges of two pipes of the gas insulated switchgear. Reference numeral 2 denotes a plurality of insertion holes formed in the peripheral portion of the spacer 1, which communicates with the insertion holes of the flanges of both pipes, bolts are inserted into the insertion holes and the insertion holes 2, and nuts are screwed onto the bolts. Connect both pipes.

Reference numeral 3 denotes four recesses formed on the upper, lower, left and right sides of the center of the front surface of the spacer 1, respectively.
Reference numeral 4 denotes a convex portion formed at each of the concave portions 3 on the rear surface of the spacer 1, and 5 denotes each concave portion 3 except the upper concave portion 3 and the convex portion 4.
And a through hole formed by penetrating the central portion of the convex portion 4, and 6 is a holding portion formed at the peripheral edges of both ends of the through hole 5.

Reference numeral 7 designates a conductor made of an aluminum alloy or copper alloy whose peripheral surface has been subjected to adhesion processing such as honing processing or knurling processing, and 8 designates a bulging portion formed in the central portion of the peripheral surface of the conductor 7. , The conductor 7 penetrates the through hole 5 of the spacer 1, and the bulging portion 8 is molded while being held by both holding portions 6,
The conductor 7 is embedded in and supported by the spacer 1. 9
Are a plurality of screw holes for connecting other conductors, which are formed in the peripheral portions of both end surfaces of the conductor 7.

However, as shown in FIG. 5, when the conductor 7 and the spacer 1 are closely adhered to each other and molded, there is a difference in linear expansion coefficient between the material of the conductor 7 and the epoxy resin of the spacer 1. A thermal stress is generated at the boundary between the conductor 7 and the spacer 1 due to a temperature change of the conductor 7 or a temperature rise of the conductor 7 due to energization in use, and the thermal stress causes an F portion shown by an arrow in FIG. There is a high possibility that a crack will occur at the end of the through hole 5 on the concave portion 3 side. This is because the amount of resin in the F portion where the thermal stress at the resin end portion is high is small and the resin cannot withstand the thermal stress.

Therefore, in order to avoid the occurrence of cracks due to thermal stress, the measures shown in FIG. 6 are taken. That is, the conductor 7
Honing processing or knurling processing is applied only to the peripheral surface of the bulging portion 8 of the spacer 1, and the peripheral surface of the predetermined length L of the end portion of the through hole 5 of the spacer 1 on the concave portion 3 side, that is, 3 mm to 5 mm is provided. The peripheral surface of the corresponding conductor 7 is not subjected to the adhesion processing, the peripheral surface is not adhered to the spacer 1, and the amount of resin is increased in the high thermal stress portion of the end of the through hole 5 on the concave portion 3 side, Improves strength and prevents cracks from occurring. At this time, a wedge-shaped minute gap portion 10 may be formed at the end of the through hole 5 of the spacer 1 on the concave portion 3 side.

[0007]

In the case of the conventional conductor supporting device of FIG. 6, the SF is installed in the gas insulated switchgear.
_In a situation where it is actually used in an insulating gas such as ₆ ,
A high voltage is applied to the conductor 7, and a triple junction known as peculiarity of the electric field in the insulating gas, that is, a triple junction point of the conductor 7 (electrode) -spacer 1 (insulator) -insulating gas, It is formed in the wedge-shaped minute gap portion 10 shown in FIG. 6, the electric field in this portion becomes high, and the flashover voltage becomes lower than the expected value. That is, the dielectric constant of the spacer 1, which is an insulator, increases, local concentration of the electric field occurs in the minute gap portion 10, electron avalanche is formed, the withstand voltage performance deteriorates, and creeping flashover occurs at a low voltage. There is a problem. The present invention takes note of the above points,
Conductor support that prevents the occurrence of cracks at the recessed end of the through hole of the insulating spacer, eliminates the wedge-shaped minute gap that forms the triple junction, improves withstand voltage performance, and prevents flashover accidents. The purpose is to provide a device.

[0008]

In order to solve the above-mentioned problems, the conductor supporting device of the present invention includes an insulating spacer interposed between both flanges of two pipes of a gas-insulated switchgear, and a spacer formed on the spacer. A plurality of recessed portions, conductors penetrating through the through holes at the center of each recess, a peripheral surface of a predetermined length at the recessed end of the through hole, and a gap between the peripheral surface of the conductor. It is provided with cylindrical voids having equal intervals.

[0009]

According to the conductor supporting device of the present invention constructed as described above, both peripheral surfaces are provided between the peripheral surface of the conductor and the peripheral surface of the conductor having the predetermined length at the recess side end of the through hole. Since the cylindrical gaps having the same gap size are provided, the both peripheral surfaces do not adhere to each other, and the amount of resin is increased in a portion of the end portion where the thermal stress is high,
Strength is improved and cracks are prevented from occurring. Further, the wedge-shaped minute gap portion forming the triple junction is eliminated, the withstand voltage performance is improved, and the flashover accident is prevented.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment will be described with reference to FIGS. In these drawings, the same reference numerals as those in FIGS. 3 and 6 indicate the same or corresponding ones, and the different points are as follows. Reference numeral 11 denotes an air gap in the cylindrical field, and between the peripheral surface of the conductor 7 and the peripheral surface of the conductor 7 having the predetermined length L at the end of the through hole 5 of the insulating spacer 1 on the concave portion 3 side, the gap dimension g of both peripheral surfaces is provided. Are formed at equal intervals.

Then, only the peripheral surface of the bulging portion 8 of the conductor 7 is subjected to a contacting processing such as homing processing or knurling processing so as to correspond to the peripheral surface of a predetermined length L at the end of the through hole 5 on the concave portion 3 side. The peripheral surface of the conductor 7 is not subjected to the adhesion processing, the peripheral surfaces do not adhere to each other, and the resin amount is increased at the end portion where the thermal stress is high, the strength is improved, and the occurrence of cracks is prevented. As a result, the wedge-shaped minute gap portion forming the triple junction is eliminated, and the withstand voltage performance is improved.

It is appropriate that the L dimension is 2 mm to 10 mm and the g dimension is 2 mm to 4 mm. When L <2, the resin amount at the end of the through hole 5 on the concave portion 3 side is small and cracks due to thermal stress are generated. When L> 10, it becomes difficult to perform die cutting due to the casting technique, and the casting state at the inner part of the void 11 cannot be confirmed. When g <2, when L> 10, Similarly, due to problems in casting technology, it is difficult to set and release the casting, and when g> 4, a wedge-shaped minute gap portion forming a triple junction is formed, resulting in low withstand voltage performance. Become.

In the above embodiment, the gap 11 is formed between the peripheral surface of the conductor 7 and the peripheral surface of the conductor 7 having a predetermined length at the end of the through hole 5 on the concave portion 3 side. It may be formed between the peripheral surface of the conductor 7 and the peripheral surface of the conductor 7 having a predetermined length at the end of the convex portion 4 on the side of the convex portion 4, and the same effect as that of the above-described embodiment is obtained.

[0014]

Since the present invention is constructed as described above, it has the following effects. The conductor supporting device of the present invention includes a conductor 7 between the peripheral surface of the insulating spacer 1 having a predetermined length L at the end of the through hole 5 on the concave portion 3 side and the peripheral surface of the conductor 7.
Since the cylindrical gaps 11 having the same gap dimension g on both peripheral surfaces are provided, the peripheral surfaces are not brought into close contact with each other, and the amount of resin is increased in the high thermal stress portion of the end portion to improve the strength. It is possible to prevent the occurrence of cracks. Further, it is possible to eliminate the wedge-shaped minute gap portion forming the triple junction, improve the withstand voltage performance, and prevent a flashover accident.

[Brief description of drawings]

FIG. 1 is a cut right side view of an embodiment of the present invention.

FIG. 2 is an enlarged view of a part of FIG.

3A and 3B are a front view and a cut right side view of A of a conventional example.

FIG. 4 is a cutaway right side view of the portion of FIG. 3B.

FIG. 5 is an enlarged view of FIG.

FIG. 6 is a partially cutaway right side view of another conventional example.

[Explanation of symbols]

 1 Insulating Spacer 3 Recess 5 Through Hole 7 Conductor 11 Void

Claims (1)

[Claims] 1. An insulating spacer interposed between both flanges of two tubular bodies of a gas-insulated switchgear, a plurality of recesses formed in the spacer, and a through hole at the center of each recess. Conductor support including a conductor embedded in the through hole, a peripheral surface having a predetermined length at the end portion of the through hole on the concave side, and a cylindrical void having a uniform gap between the peripheral surface of the conductor and the peripheral surface. apparatus.