Three-post insulator, gas-insulated metal-enclosed power transmission line and switch equipment

Abstract

The utility model relates to the field of insulators or insulating objects distinguished according to shape characteristics, in particular to a three-post insulator, a gas-insulated metal-enclosed power transmission line and a switch device. The three-post insulator comprises an insulator, the insulator comprises a central supporting part and a post, one end of the post is provided with an insert, one end of the insert is embedded into the corresponding post to form an inner end, the other end of the insert is an outer end, the inner end of the insert is provided with an anchoring head, the anchoring head is in a mushroom head shape, and the anchoring head is in smooth transition connection with other parts of the insert. The anchoring head is in a mushroom head shape and is in smooth transition connection with other parts of the insert, so that the binding force between the insert and the supporting column can be increased, the mushroom-head-shaped anchoring head can bring a larger surface, and the effect of controlling the creepage electric field intensity can be achieved. In conclusion, the three-post insulator solves the problems that the combination strength of the insert and the post of the existing three-post insulator is insufficient, and the surface electric field is concentrated.

Description

Technical Field

[0001] This utility model relates to the field of insulators or insulating objects classified by shape characteristics, and in particular to a three-post insulator and GIL and GIS. Background Technology

[0002] Three-post insulators are key components of high-voltage direct current gas-insulated metal-enclosed transmission lines (GILs) and gas-insulated metal-enclosed switchgear (GIS), serving to support the center conductor and provide electrical insulation in both GILs and GIS.

[0003] Chinese invention patent application CN117038232A, published on November 10, 2023, discloses a three-post insulator and busbar for a high-voltage DC GIL / GIS abdominal shield. The application discloses a typical three-post insulator structure, comprising a support cylinder and an insulator covering the support cylinder. The support cylinder allows the central conductor of the GIL or GIS busbar to pass through. The insulator includes a central support portion covering the support cylinder and three posts extending radially outward from the central support portion. The three posts are evenly distributed around the outer periphery of the central support portion, with the same included angle between them. An insert, truncated cylindrical in shape, is provided at the end of each post furthest from the support cylinder. One end of the insert is embedded in the end of the corresponding post, and the other end has a mounting hole. During use, the post can be connected to a corresponding sliding roller or fixed to a particle collector through the mounting hole.

[0004] The connection strength between the end of the insert embedded in the support and the support, as well as the magnitude of the surface electric field strength at that end, directly affect the safe operation of GIL / GIS products. In the aforementioned patent application, the circumferential surface of the insert is a smooth plane of uniform diameter. However, inserts are typically cast and fixed into the support during the insulator casting process. This structure results in limited axial bonding force between the insert and the support, potentially leading to detachment at the connection point. Furthermore, the small end area of ​​the insert embedded in the support makes it prone to electric field concentration.

[0005] To solve the above problems, such as Figure 1-2As shown, some existing three-post insulators have annular grooves 21 on the outer circumferential surface of their inserts 2 to increase the bonding force between the inserts 2 and the posts 11. This type of three-post insulator can be seen in Chinese utility model patent CN218996445U, published on May 9, 2023. Specifically, the specification of this patent discloses a lightweight three-post insulator for three-phase common-box GIS / GIL. In this patent, annular grooves arranged around the inserts are provided on the outer circumferential surface of the inserts, which can increase the bonding force between the inserts and the posts to a certain extent. However, the increase is limited, and it fails to solve the problem of electric field concentration at the end where the insert is embedded in the post.

[0006] In addition, Chinese invention patent application with publication number CN111370188 A and publication date of July 3, 2020 discloses a three-phase three-post insulator for a three-phase common-box compact GIS / GIL. In this patent, a stepped surface is provided on the outer peripheral surface of the insert, facing away from the end of the insert that is embedded in the post. The stepped surface can increase the bonding force between the insert and the post to a certain extent, but its increase effect is still limited, and it also fails to solve the problem of electric field concentration at the end of the insert that is embedded in the post. Utility Model Content

[0007] The purpose of this invention is to provide a three-post insulator to solve the problems of insufficient bonding strength between the insert and the post in existing three-post insulators and the concentration of electric field along the surface.

[0008] Meanwhile, the purpose of this utility model is also to provide a gas-insulated metal-enclosed transmission line and a gas-insulated metal-enclosed switchgear that include the above-mentioned three-post insulators, so as to solve the above problems.

[0009] To solve the above problems, the three-post insulator of this utility model adopts the following technical solution: The three-post insulator includes an insulator body, the insulator body includes a central support portion and post extending radially outward from the central support portion, an insert is provided at one end of the post away from the central support portion, one end of the insert is embedded into the corresponding post to form an inner end, and the other end is an outer end, the inner end of the insert is provided with an anchoring head that is anchored to the corresponding post, the anchoring head is mushroom-shaped, and the anchoring head is smoothly connected to the other parts of the insert.

[0010] Furthermore, the longitudinal section of the anchor head is divided into an intermediate section and an edge section located between the two intermediate sections. The intermediate section forms an intermediate arc, and the edge section forms an edge arc. The radius of the edge arc is smaller than that of the intermediate arc and they are symmetrical to each other.

[0011] Furthermore, the intermediate arc is tangent to the edge arc.

[0012] Furthermore, the diameter of the end of the support near the corresponding insert is larger than the diameter of the segment adjacent to that end.

[0013] Furthermore, the insulator is an epoxy resin insulator.

[0014] Furthermore, the center of the central support portion is provided with a coaxial mounting hole, and a support cylinder for supporting the corresponding conductor is provided in the mounting hole.

[0015] Furthermore, the central support portion has three conductor through holes arranged around the center line, and a support cylinder for supporting the corresponding conductor is arranged in the conductor through holes.

[0016] Beneficial Effects: This utility model presents an improved three-post insulator. Specifically, the outer end of the insert of the three-post insulator is provided with an anchoring head that anchors to the corresponding post. The anchoring head is mushroom-shaped and smoothly transitions with the other parts of the insert, thus achieving an anchoring effect and greatly increasing the bonding force between the insert and the post. Furthermore, the mushroom-shaped anchoring head provides a larger surface area, and the smooth transition between the anchoring head and the other parts of the insert also homogenizes the electric field, thereby controlling the surface electric field intensity. In summary, this utility model solves the problems of insufficient bonding strength between the insert and the post and surface electric field concentration in existing three-post insulators.

[0017] The gas-insulated, metal-enclosed transmission line of this utility model adopts the following technical solution:

[0018] A gas-insulated metal-enclosed transmission line includes an outer cylinder and a conductor disposed within the outer cylinder. The conductor is supported by a three-post insulator disposed within the outer cylinder. The three-post insulator includes an insulator body, which includes a central support portion and post members extending radially outward from the central support portion. An insert is disposed at one end of each post member away from the central support portion. One end of the insert is embedded into the corresponding post member to form an inner end, and the other end is an outer end. An anchoring head is disposed at the inner end of the insert member to anchor and cooperate with the corresponding post member. The anchoring head is mushroom-shaped, and the anchoring head is smoothly transitioned to the other parts of the insert member.

[0019] Furthermore, the longitudinal section of the anchor head is divided into an intermediate section and an edge section located between the two intermediate sections. The intermediate section forms an intermediate arc, and the edge section forms an edge arc. The radius of the edge arc is smaller than that of the intermediate arc and they are symmetrical to each other.

[0020] Furthermore, the intermediate arc is tangent to the edge arc.

[0021] Furthermore, the diameter of the end of the support near the corresponding insert is larger than the diameter of the segment adjacent to that end.

[0022] Furthermore, the insulator is an epoxy resin insulator.

[0023] Furthermore, the center of the central support portion is provided with a coaxial mounting hole, and a support cylinder for supporting the corresponding conductor is provided in the mounting hole.

[0024] Furthermore, the central support portion has three conductor through holes arranged around the center line, and a support cylinder for supporting the corresponding conductor is arranged in the conductor through holes.

[0025] Beneficial Effects: This utility model of a gas-insulated metal-enclosed transmission line is an improved invention. Specifically, the outer end of the insert of the three-post insulator is provided with an anchoring head that anchors to the corresponding post. The anchoring head is mushroom-shaped and smoothly transitions with the other parts of the insert, thus achieving an anchoring effect and greatly increasing the bonding force between the insert and the post. Furthermore, the mushroom-shaped anchoring head provides a larger surface area, and the smooth transition between the anchoring head and the other parts of the insert also homogenizes the electric field, thereby controlling the surface electric field intensity. In summary, this utility model solves the problems of insufficient bonding strength between the insert and the post and surface electric field concentration in existing three-post insulators.

[0026] The gas-insulated metal-enclosed switchgear of this utility model adopts the following technical solution:

[0027] A gas-insulated metal-enclosed switchgear includes an outer cylinder and a conductor disposed within the outer cylinder. The conductor is supported by a three-post insulator disposed within the outer cylinder. The three-post insulator includes an insulator body, which includes a central support portion and post members extending radially outward from the central support portion. An insert is disposed at one end of each post member away from the central support portion. One end of the insert is embedded into the corresponding post member to form an inner end, and the other end is an outer end. An anchoring head, which is mushroom-shaped, is disposed at the inner end of the insert member for anchoring engagement with the corresponding post member. The anchoring head is smoothly transitioned to the other parts of the insert member.

[0028] Furthermore, the longitudinal section of the anchor head is divided into an intermediate section and an edge section located between the two intermediate sections. The intermediate section forms an intermediate arc, and the edge section forms an edge arc. The radius of the edge arc is smaller than that of the intermediate arc and they are symmetrical to each other.

[0029] Furthermore, the intermediate arc is tangent to the edge arc.

[0030] Furthermore, the diameter of the end of the support near the corresponding insert is larger than the diameter of the segment adjacent to that end.

[0031] Furthermore, the insulator is an epoxy resin insulator.

[0032] Furthermore, the center of the central support portion is provided with a coaxial mounting hole, and a support cylinder for supporting the corresponding conductor is provided in the mounting hole.

[0033] Furthermore, the central support portion has three conductor through holes arranged around the center line, and a support cylinder for supporting the corresponding conductor is arranged in the conductor through holes.

[0034] Beneficial Effects: This utility model presents an improved invention of a gas-insulated metal-enclosed switchgear. Specifically, the outer end of the insert of the three-post insulator is provided with an anchoring head that anchors to the corresponding post. The anchoring head is mushroom-shaped and smoothly transitions with the other parts of the insert, thus achieving an anchoring effect and greatly increasing the bonding force between the insert and the post. Furthermore, the mushroom-shaped anchoring head provides a larger surface area, and the smooth transition between the anchoring head and the other parts of the insert also homogenizes the electric field, thereby controlling the surface electric field intensity. In summary, this utility model solves the problems of insufficient bonding strength between the insert and the post and surface electric field concentration in existing three-post insulators. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the existing three-post insulator;

[0036] Figure 2 This is a schematic diagram of the insert structure shown in the image;

[0037] Figure 3 This is a schematic diagram of the structure of one embodiment of the three-post insulator of this utility model;

[0038] Figure 4 yes Figure 3 A schematic diagram of the insert structure.

[0039] Figure 1 In the middle: 1. Insulator; 11. Support; 2. Insert; 21. Annular groove; 22. Anchor head; 23. Connecting hole; 3. Support cylinder. Detailed Implementation

[0040] The features and performance of this utility model will be further described in detail below with reference to the embodiments.

[0041] Three-post insulators are used to support the conductors of GIL or GIS within the outer cylinder of the busbar. In practical engineering, due to the radial dimension D of its outer end, i.e., the end closest to the corresponding post 11 (e.g., ...), ... Figure 3 There are certain requirements for the inner end of the insert 2, that is, the diameter of the end that is embedded into the corresponding support 11. Therefore, by designing the shape of the inner end of the insert 2 to form a structure similar to the anchor head in the construction field, the bonding force between it and the support 11 can be increased, and the bonding strength between the two can be guaranteed. At the same time, by appropriately enlarging the end face of the inner end of the insert 2, the electric field can be homogenized and the surface field strength can be reduced.

[0042] Based on the above inventive concept, a basic implementation of the three-post insulator of this utility model is as follows: The three-post insulator includes an insulator 1, which includes a central support portion and three posts 11 extending radially outward from the central support portion. There are three posts 11, and any two adjacent posts 11 form a 120° angle in the circumferential direction of the central support portion. The central support portion and the posts 11 are combined to form a star-shaped structure. The above shape is a typical shape of the three-post insulator, so it will not be described in detail.

[0043] As a typical implementation method, such as Figure 3 As shown, a support cylinder 3 is coaxially arranged in the central support section. The support cylinder 3 is covered by an insulator 1 and is used for the conductors of GIL or GIS to pass through. This type of three-post insulator is suitable for phase-separated busbars. When applied to a three-phase common-box busbar, three support cylinders 3 can be arranged around the axis in the central support section to support the three-phase conductors of the busbar respectively.

[0044] An insert 2 is provided at one end of the three pillars 11 away from the central support. The inner end of the insert 2 is embedded into the pillar 11, and the outer end extends out of the end of the pillar 11 away from the central support. A connecting hole 23 is provided at the outer end of the insert 2 to connect a sliding roller or a particle collector. The structure of the outer end of the insert is prior art and will not be described in detail here.

[0045] like Figure 4As shown, unlike existing technologies, in the three-post insulator of this invention, the inner end of the insert 2 is provided with an anchoring head 22 that is anchored to the corresponding post. The anchoring head 22 is mushroom-shaped, and the anchoring head 22 is smoothly connected to the other parts of the insert. Since the insulator 1 is cast from epoxy resin, the support cylinder 3 and the insert 2 are integrally cast into it during the molding process of the insulator 1. By setting the mushroom-shaped anchoring head 22, the insert 2 can be anchored in the corresponding post 11. The mushroom-shaped anchoring head 22 and the smooth transition between it and the other parts of the insert 2 will result in a larger surface area. The smooth transition between the anchoring head 22 and the other parts of the insert 2 can also homogenize the electric field, thereby achieving the effect of controlling the surface electric field strength.

[0046] Based on the above basic implementation method, as a preferred implementation method, such as... Figure 4 As shown, the longitudinal section of the anchor head 22 is divided into a middle section and edge sections located between the two middle sections. The middle section forms a central arc, and the edge sections form arcs a and a. ， The outer arc is centered on the center of the circle, and the radius of the outer arc is smaller than that of the inner arc and they are symmetrical to each other. The inner arc and the outer arc are tangent to each other. This divides the outer surface of the anchor head 22 into a spherical surface in the middle and an arc surface at the edge, which can better homogenize the electric field and avoid the generation of air bubbles during the casting process of the insulator 1.

[0047] Although in the preferred embodiment described above, the longitudinal section of the end face of the anchor head is designed as a structure combining a central arc and an edge arc, and the outer surface of the anchor head 22 is designed as a combination of a central spherical surface and an edge arc surface, those skilled in the art should understand that in other embodiments, the outer surface of the anchor head can also be designed as a spherical surface or a planar shape, taking into account the electric field distribution and ensuring a smooth transition at all points.

[0048] Based on the above specific embodiments, as a preferred embodiment, the diameter of the end of the support 11 closest to the corresponding insert 2 is larger than the diameter of the section adjacent to that end. This will help to increase the diameter of the anchor head and improve the mechanical strength of the three-support insulator.

[0049] The embodiments of the gas-insulated metal-enclosed transmission line of this utility model are as follows:

[0050] The GIL of this utility model includes an outer cylinder and a conductor disposed inside the outer cylinder. The conductor is supported by the three-post insulator of this utility model. The structure of the outer cylinder and the conductor is prior art. The structure of the three-post insulator has been described in detail above and will not be repeated here.

[0051] Implementation methods of the gas-insulated metal-enclosed switchgear of this utility model:

[0052] The GIS of this utility model includes an outer cylinder and a conductor disposed inside the outer cylinder. The conductor is supported by a three-post insulator of this utility model. The structure of the outer cylinder and the conductor is prior art. The structure of the three-post insulator has been described in detail above and will not be repeated here.

[0053] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. The patent protection scope of the present utility model shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present utility model shall also be included within the protection scope of the present utility model.

Claims

1. A three-post insulator, comprising an insulator body, the insulator body including a central support portion and posts extending radially outward from the central support portion, wherein an insert is provided at one end of each post away from the central support portion, one end of the insert being embedded into a corresponding post to form an inner end, and the other end being an outer end, characterized in that, The inner end of the insert is provided with an anchoring head that is anchored to the corresponding post. The anchoring head is mushroom-shaped and is smoothly connected to the other parts of the insert.

2. The three-post insulator according to claim 1, characterized in that, The longitudinal section of the anchor head is divided into an intermediate section and an edge section located between the two intermediate sections. The intermediate section forms an intermediate arc, and the edge section forms an edge arc. The radius of the edge arc is smaller than that of the intermediate arc and they are symmetrical to each other.

3. The three-post insulator according to claim 2, characterized in that, The middle arc is tangent to the edge arc.

4. The three-post insulator according to any one of claims 1-3, characterized in that, The diameter of the end of the support near the corresponding insert is larger than the diameter of the segment adjacent to that end.

5. The three-post insulator according to claim 4, characterized in that, The insulator is an epoxy resin insulator.

6. The three-post insulator according to any one of claims 1-3, characterized in that, The center of the central support portion is provided with a coaxial mounting hole, and a support cylinder for supporting the corresponding conductor is provided in the mounting hole.

7. The three-post insulator according to claim 4, characterized in that, The central support portion has a coaxial mounting hole at its center, and a support cylinder is installed in the mounting hole.

8. The three-post insulator according to any one of claims 1-3, characterized in that, The central support section has three conductor holes arranged around the center line, and a support cylinder for supporting the corresponding conductor is arranged in the conductor holes.

9. A gas-insulated metal-enclosed transmission line, comprising an outer cylinder and a conductor disposed within the outer cylinder, the conductor being supported by a three-post insulator disposed within the outer cylinder, characterized in that, The three-post insulator is the three-post insulator as described in any one of claims 1-8.

10. A gas-insulated metal-enclosed switchgear, comprising an outer cylinder and a conductor disposed within the outer cylinder, the conductor being supported by a three-post insulator disposed within the outer cylinder, characterized in that, The three-post insulator is the three-post insulator as described in any one of claims 1-8.

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