CN216902415U

CN216902415U - Basin-type insulator

Info

Publication number: CN216902415U
Application number: CN202123186606.3U
Authority: CN
Inventors: 陈雪如; 张建宏; 王振良
Original assignee: Macaudi Xiamen Intelligent Electric Co ltd
Current assignee: Macaudi Xiamen Intelligent Electric Co ltd
Priority date: 2021-12-17
Filing date: 2021-12-17
Publication date: 2022-07-05
Anticipated expiration: 2031-12-17

Abstract

The utility model discloses a basin-type insulator, which comprises a central conductor insert, an insulator and a shielding case, wherein the central conductor insert is connected with a conductor, and an insulating gas is filled in an area between the conductor and the insulator; the shielding cover comprises a first part, a second part and a third part which are smoothly connected in sequence; the first portion is connected to the conductor; the second portion is in a groove shape recessed toward the insulator; the third portion extends from the edge of the second portion to the side where the conductor is located. According to the utility model, the shield cover is arranged, particularly the design of the 'groove' of the shield cover is adopted, so that the three-intersection region is positioned in the shield region, the influence of wedge-shaped gaps is eliminated, the field intensity of the three-intersection region is reduced, the overall electric field distribution is improved, and the risk of surface flashover of the basin-type insulator is reduced.

Description

Basin-type insulator

Technical Field

The utility model relates to the field of high-voltage switch equipment, in particular to a basin-type insulator in the field of high-voltage switch equipment.

Background

The basin-type insulator plays a role in isolating a gas chamber, connecting and supporting a conductor, insulating and the like in GIS or GIL switchgear. The basin-type insulator is used as a weak link in a GIS or a GIL, and the surface flashover of the basin-type insulator is an important reason for the failure of the switch equipment. In order to ensure the reliable operation of the GIS switchgear, the basin-type insulator is designed in consideration of not only the mechanical strength of the structure thereof, but also the reliability of the electrical performance thereof, and the uniformity of the electric field distribution on the surface of the insulator, the surface of the conductor, and the surface of the housing.

At present, electric field analysis aiming at the basin-type insulator and the components thereof mainly focuses on the surface of the basin-type insulator and the shielding cover of a central conductor, the electric field distribution at the three intersection points of the basin-type insulator and a ground potential shell is focused, and the electric field distribution in the three intersection areas formed among the conductor, the insulator of the basin-type insulator and insulating gas is rarely focused.

The distribution of the electric field in the triple crossing region formed between the conductor and the insulator is also important, if the connection part of the conductor and the insulator is not properly designed, an arc-shaped wedge-shaped air gap is easily left, and due to the existence of the wedge-shaped air gap, the electric field in the air gap region is high, and the partial discharge phenomenon is easily caused. In addition, metal chips or other impurities are likely to remain in this region, and surface flashover is also caused. The structural design (partial) of a 420kV basin-type insulator is shown in figure 1, and a partial enlarged view (wedge-shaped gap) is shown in figure 2. The basin-type insulator is applied with lightning impulse voltage, and through simulation calculation, as shown in figure 3, the electric field of the wedge-shaped gap can reach 29.272kV/mm, which is higher than the allowable field intensity of 24kV/mm on the surface of a high-potential conductor.

Therefore, it is necessary to optimize the electric field for the three-crossing region formed by the conductor and the basin insulator to further improve the insulating performance of the basin insulator.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a basin-type insulator with reliable shielding effect so as to effectively improve the electric field distribution of a three-intersection region between a conductor and the basin-type insulator.

In order to realize the purpose, the utility model adopts the following technical scheme:

a basin-type insulator comprises a central conductor insert and an insulator, wherein the central conductor insert is connected with a conductor, an insulating gas is filled in an area between the conductor and the insulator, and a shielding cover is further included; the shielding cover comprises a first part, a second part and a third part which are smoothly connected in sequence; the first portion is connected to the conductor; the second portion is in a groove shape recessed toward the insulator; the third portion extends from the edge of the second portion to the side where the conductor is located.

In one embodiment, the lowest point of the second portion is lower than the lowest point of the first portion by 2 to 10mm in a radial direction of the insulator.

In one embodiment, the first portion is flat along a cross-section of the shield; the conductor is provided with a mounting step hole corresponding to the first part, and the first part is connected with the hole wall of the mounting step hole.

In one embodiment, the first portion is detachably locked to a wall of the mounting step hole by a fastener.

In one embodiment, the lowest point of the second portion is lower than the lowest point of the fastener in a radial direction of the insulator.

In one embodiment, the third portion is arc-shaped with its arc opening facing the conductor.

In one embodiment, it further comprises a flange distributed on the other side of the insulator with respect to the center conductor insert; the shielding ring is arranged in the insulator and positioned on the side of the flange, and the shielding ring is electrically connected with the flange and then grounded; the central conductor insert, the flange and the shielding ring are integrally cast through insulating resin.

In one embodiment, the sealing device further comprises a sealing ring, a sealing groove is formed in the side, where the flange is located, of the insulator, and the sealing ring is installed in the sealing groove to seal the tank body to be connected.

Compared with the background art, the utility model has the following advantages by adopting the technical scheme:

according to the utility model, the shield cover is arranged, particularly the design of the 'groove' of the shield cover is adopted, so that the three-intersection region is positioned in the shield region, the influence of wedge-shaped gaps is eliminated, the field intensity of the three-intersection region is reduced, the overall electric field distribution is improved, and the risk of surface flashover of the basin-type insulator is reduced.

The utility model installs the shield on the conductor through the fastener, not designed as an organic whole with the conductor, if the shield needs to be replaced because of the defect, only the shield can be disassembled and replaced, and the whole conductor does not need to be replaced.

The lowest point of the second part of the utility model is lower than the lowest point of the fastener, which can shield the tip discharge which may be caused by the fastener, so that the electric field at the position can be effectively shielded.

The utility model is provided with the shielding ring, and the shielding ring, the flange and the tank body are all positioned at the ground potential through the shielding ring, so that the air gap field intensity between the tank body and the epoxy resin insulator can be effectively reduced.

Drawings

FIG. 1 shows a partial structure design of a 420kV basin-type insulator;

FIG. 2 is a partial detail view of FIG. 1;

FIG. 3 is a result of an electric field simulation calculation for the structure shown in FIG. 1;

fig. 4 is a schematic view of a basin insulator according to the present invention;

FIG. 5 is a schematic view of a shield according to the present invention;

FIG. 6 is a result of electric field simulation calculations according to the present invention;

FIG. 7 is a further calculation result of the electric field simulation of the present invention.

Description of reference numerals:

center conductor insert 110, insulator 120, seal groove 121, shield case 130, first portion 131, bolt hole 1311, second portion 132, third portion 133, flange 140, shield ring 150, seal ring 160;

Conductor 200, mounting step hole 210, fastener 220;

an insulating gas 300;

a can 400.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the utility model and do not limit the utility model.

In the description of the present invention, it is to be understood that the terms "center", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, are not to be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or may be connected through the use of two elements or the interaction of two elements. The specific meanings of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

Examples

Referring to fig. 4, the present invention discloses a basin-type insulator, which includes a central conductor insert 110, an insulator 120, a shield cover 130 and a flange 140.

The central conductor insert 110 and the flange 140 are distributed on two sides of the insulator 120, and the central conductor insert 110 and the flange 140 are connected into a whole by pouring the insulator 120, the central conductor insert 110 is used for realizing connection with the conductor 200, and the flange 140 is used for connecting with the tank 400. In this embodiment, the insulator 120 is cast with epoxy. The region between conductor 200 and insulator 120 is filled with insulating gas 300. In this embodiment, the insulating gas 300 is SF6 gas.

The shield cover 130 includes a first portion 131, a second portion 132, and a third portion 133 that are smoothly connected in sequence. The first portion 131 is a connecting portion for connecting the conductor 200. The second portion 132 is recessed toward the insulator 120. The third portion 133 of the first conductor extends from the edge of the second portion 132 to the side of the conductor 200. Thus, a triple intersection region is formed between the shield 130, the insulator 120 and the insulating gas 300.

By configuring the shield cover 130 as above, the second portion 132 is lower than the first portion 131 and the third portion 133 along the cross-sectional direction of the shield cover 130, that is, the surface of the second portion 132 forms the lowest point, and the lowest groove structure forms a shielding region with the conductor 200, so that the electric field in the region is greatly reduced, and the wedge gap is eliminated.

Specifically, along the cross section of the shielding cover 130, the first portion 131 of the shielding cover 130 is in a straight shape, the second portion 132 is formed by a first arc section and a second arc section, the third portion 133 is in an arc shape, the straight section of the first portion 131 is tangent to the first arc section of the second portion 132, and the second arc section of the second portion 132 is respectively tangent to the first arc section of the second portion 132 and the arc of the third portion 133 for smooth transition, i.e., the groove-shaped structure is formed. Thus, the first arc section and the second arc section are both arranged below the straight section. The arc of the third portion 133 faces the conductor 200.

In the present embodiment, the second portion 132 has a recess difference relative to the first portion 131 in the radial direction of the insulator 120 such that the lowest point of the second portion 132 is lower than the lowest point of the first portion 131 by 2 to 10 mm.

To facilitate the mounting of the shield can 130, a mounting stepped hole 210 corresponding to the first portion 131 is formed in the conductor 200, and the first portion 131 is connected to a hole wall of the mounting stepped hole 210. In the present embodiment, the first portion 131 is detachably locked to the wall of the mounting stepped hole 210 by the fastening member 220, so that if the shield cover 130 is replaced due to a defect, only the shield cover 130 can be detached and replaced without replacing the entire conductor 200.

In order to shield the fastener 220 from possible tip discharge and to effectively shield the electric field there, the lowest point of the second portion 132 is lower than the lowest point of the fastener 220 in the radial direction of the insulator 120, so that the fastener 220 can be shielded from possible tip discharge by the second portion 132.

The present invention also includes a shield ring 150. The shielding ring 150 is arranged in the insulator 120 and is located on the side of the insulator 120 close to the flange 140, and the shielding ring 150 is electrically connected with the flange 140 and then grounded; through the arrangement of the shielding ring 150, the field intensity of the intersection region of the insulator 120, the SF6 gas at the ground potential end and the tank body 400 can be reduced, the electric field distribution of the ground potential three-intersection region is improved, and the insulation effect is improved. In this embodiment, the center conductor insert 110, the flange 140, and the shield ring 150 are integrally molded by insulating resin.

In addition, the insulator 120 is provided with a sealing groove 121 at the side of the flange 140, and a sealing ring 160 is installed in the sealing groove 121 to seal the can body 400 to be connected, ensuring the airtightness of SF6 gas.

The basin-type insulator of the utility model is formed by modifying a conductor 200 and adding a shielding cover 130 on the basis of a certain 420kV basin-type insulator shown in figure 1, by applying lightning impulse voltage, and through electric field simulation calculation, the simulation result is shown in figure 6, the field intensity of a gap at the intersection region of the shielding cover 130 and an epoxy resin insulator 120 is 5.129kV/mm, the field intensity at a fastener 220 region is greatly reduced, as shown in figure 7, the field intensity at the lowest point of a 'groove' of the shielding cover 130 is 20.673kV/mm, and is reduced by 29.4 percent compared with the wedge-shaped gap field intensity of the basin-type insulator adopting the structure shown in figure 1.

It will be evident to those skilled in the art that the utility model is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the utility model being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present specification describes embodiments, not every embodiment includes only a single embodiment, and such description is for clarity purposes only, and it is to be understood that all embodiments may be combined as appropriate by one of ordinary skill in the art to form other embodiments as will be apparent to those of skill in the art from the description herein.

Claims

1. The utility model provides a basin formula insulator, its includes center conductor inserts and insulator, the center conductor inserts is connected with the conductor, the conductor with regional packing between the insulator has insulating gas, its characterized in that:

The shielding cover, the insulator and the insulating gas form a three-intersection region; wherein, the first and the second end of the pipe are connected with each other,

the shielding cover comprises a first part, a second part and a third part which are smoothly connected in sequence;

the first portion is connected to the conductor;

the second portion is in a groove shape recessed toward the insulator;

the third portion extends from the edge of the second portion to the side where the conductor is located.

2. A basin-type insulator as claimed in claim 1, wherein:

the lowest point of the second part is 2-10 mm lower than the lowest point of the first part along the radial direction of the insulator.

3. A basin insulator as claimed in claim 1, characterised in that:

the first portion is flat along a cross-section of the shield; the conductor is provided with a mounting step hole corresponding to the first part, and the first part is connected with the hole wall of the mounting step hole.

4. A basin insulator as claimed in claim 3, characterised in that:

the first part is detachably locked on the hole wall of the mounting step hole through a fastener.

5. A basin insulator according to claim 4, characterised in that:

the lowest point of the second portion is lower than the lowest point of the fastener in a radial direction of the insulator.

6. A basin-type insulator as claimed in claim 1, wherein:

the third part is arc-shaped, and an arc opening of the third part faces the conductor.

7. A basin-type insulator as claimed in claim 1, wherein:

the flange is distributed on the other side of the insulator relative to the central conductor insert;

the shielding ring is arranged in the insulator and positioned on the side of the flange, and the shielding ring is electrically connected with the flange and then grounded;

the central conductor insert, the flange and the shielding ring are integrally cast through insulating resin.

8. A basin-type insulator as defined in claim 7, wherein:

the sealing ring is installed in the sealing groove to seal the tank body to be connected.