CN118538487A - GIL pillar insulator with high-voltage shielding - Google Patents

Abstract

The invention relates to the technical field of post insulators, in particular to a GIL post insulator with a high-voltage shield, which solves the defects in the prior art and comprises epoxy resin arranged in an equilateral triangle shape, wherein end grounding inserts are arranged at the triangular positions of the epoxy resin, and a center insert assembly is arranged at the three edges of the epoxy resin in a penetrating way; the central insert assembly comprises an insert main body and an insert shielding piece sleeved in the middle of the insert main body, the insert main body is fixedly connected with the insert shielding piece through a connecting guide post, and a low electric field region is formed between the insert main body and the insert shielding piece; the insert shielding piece is arranged on the outer side of the insert main body in an adding mode, the insert shielding piece is made of thin-wall metal, and the insert shielding piece is provided with a plurality of small holes, so that the bonding strength of epoxy resin and the insert shielding piece can be improved, and stress release during pouring is facilitated.

Description

A GIL post insulator with high voltage shielding

Technical Field

The invention relates to the technical field of post insulators, and in particular to a GIL post insulator with high voltage shielding.

Background Art

Rigid gas-insulated transmission line (GIL) is a kind of power transmission equipment that uses gas insulation and conductors enclosed in a metal shell. It has the advantages of large transmission capacity, high safety performance, and long service life. It can effectively solve the problem of high-voltage, long-distance, and high-drop power transmission.

As shown in Figure 7, since the GIL unit is relatively long, considering the conductor's own flexibility, transportation vibration, and electrodynamic force during live operation, the GIL conductor and shell are usually fixed with a post insulator by bolting, welding, crimping, etc., which not only plays a mechanical support role, but also ensures the insulation performance between the high-voltage conductor and the low-voltage shell;

As shown in Figure 6, the post insulator usually includes a metal center insert, a metal end grounding insert and epoxy resin. The three are combined together through a vacuum casting process and have high mechanical strength and insulation performance. However, the epoxy resin and the metal center insert are combined together through a vacuum casting process. Due to the different materials, a tiny gap may be formed at the end of the bonding surface. The product undergoes transportation vibration and long-term energized operation vibration, which causes the gap to increase. This gap is located in the high-voltage energized area. The electric field distortion at the gap is extremely large, which can easily cause flashover discharge of the post insulator and affect the safe operation of the GIL. Therefore, we propose a GIL post insulator with high-voltage shielding to solve the above problems.

Summary of the invention

The purpose of the present invention is to solve the problem that epoxy resin and metal center insert are combined together by vacuum casting process in the prior art. Due to different materials, a tiny gap may be formed at the end of the joint surface. The product is subjected to transportation vibration and long-term energized operation vibration, which causes the gap to increase. This gap is located in the high-voltage energized area. The electric field distortion at the gap is extremely large, which can easily cause flashover discharge of the post insulator. A GIL post insulator with high-voltage shielding is proposed.

In order to achieve the above object, the present invention adopts the following technical solutions:

A GIL post insulator with high voltage shielding comprises epoxy resin arranged in an equilateral triangle shape, wherein the triangles of the epoxy resin are all provided with end grounding inserts, and the three edges of the epoxy resin are all penetrated by a center insert assembly;

The central insert assembly includes an insert body and an insert shielding piece sleeved in the middle of the insert body, the insert body and the insert shielding piece are fixedly connected by connecting guide pillars, and a low electric field area is formed between the insert body and the insert shielding piece;

The insert shielding member comprises a ring-shaped joint surface, a plurality of through holes are arranged through the joint surface, and a plurality of arc surfaces are arranged upward at both ends of the joint surface;

The outer wall of the middle part of the insert body bulges upward to form an annular convex edge, and the above-mentioned insert shielding part is fixed on the annular convex edge through connecting guide pillars, so that an annular area with a narrow middle and wide ends is formed between the insert shielding part and the insert body. This annular area is the low electric field area.

As a preferred technical solution of the present invention, the end grounding insert is made of metal copper, the upper surface of the end grounding insert is higher than the outer end of the epoxy resin, and a mounting hole is opened in the middle of the end grounding insert.

As a preferred technical solution of the present invention, the number of the connecting guide pillars is three to six, and the connecting guide pillars are evenly distributed around the center of the insert shielding member, and the insert body and the insert shielding member are combined into a whole through the connecting guide pillars.

As a preferred technical solution of the present invention, the insert shielding piece is a thin-walled metal piece, and the number of arc surfaces at each end of the insert shielding piece is three to six, and the outer end of the arc surface composed of all the arc surfaces is bent inward to form a middle-low and outer-high shape.

As a preferred technical solution of the present invention, grooves are provided at both ends where the epoxy resin and the central insert assembly are combined, and the width of the grooves is not less than 3 mm to avoid small gap discharge.

As a preferred technical solution of the present invention, it also includes a positioning mechanism, which includes reinforcement rings installed at both ends of the insert body, and the reinforcement rings are fixedly connected to the ends of the insert shielding member through a plurality of connecting rods.

As a preferred technical solution of the present invention, the number of the connecting rods is three to ten, and the connecting rods are evenly distributed around the center of the reinforcement ring, and the diameter of the connecting rod at one end close to the insert shielding piece is smaller than that at the other end, which is convenient for truncation of the connecting rod.

A processing method for a GIL post insulator with a high-voltage shield comprises the following steps: before vacuum casting a metal center insert assembly, a metal end grounding insert and epoxy resin, grinding the joint surface of an insert shield in the metal center insert assembly to remove oil stains on the surface, improve the surface roughness, and further improve the bonding firmness between the epoxy resin and the insert shield.

As a preferred technical solution of the present invention, the two ends of the insert shielding member are fixed by a positioning mechanism before pouring, and the curvature of the outer surface of the insert shielding member is adjusted. The adjusted insert shielding member is fixed by the positioning mechanisms at both ends during pouring to reduce deformation of the insert shielding member during pouring.

As a preferred technical solution of the present invention, the positioning mechanism is peeled off after the pouring is completed to form the insulator.

The beneficial effects of the present invention are:

1. By adding an insert shielding part on the outside of the insert body, the insert shielding part is made of thin-walled metal and has a number of small holes, which can improve the bonding strength between the epoxy resin and the insert shielding part and facilitate stress release during pouring;

2. The outer contour of the insert shield is composed of multiple arcs. During processing, the electric field on the surface of the epoxy resin is controlled by adjusting the arc to improve the electrical performance of the post insulator;

3. By forming a low electric field area between the insert body and the insert shield, the starting point of the bonding surface between the epoxy resin and the insert body is set in the low electric field area, so that even if there is a small air gap at the end of the bonding surface, it will not cause flashover discharge of the post insulator, thereby improving the safety of GIL during operation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic cross-sectional view of a GIL post insulator with high voltage shielding proposed by the present invention;

Fig. 2 is a schematic diagram of the structure at A-A in Fig. 1;

FIG3 is a schematic structural diagram of a GIL post insulator center insert assembly with high voltage shielding proposed by the present invention;

FIG4 is a schematic structural diagram of an insert shielding member in a GIL post insulator with high voltage shielding proposed by the present invention;

FIG5 is a schematic structural diagram of a central insert assembly of a GIL post insulator with high voltage shielding proposed by the present invention during casting;

FIG6 is a schematic cross-sectional view of the structure of an existing GIL post insulator;

FIG7 is a schematic structural diagram of a GIL post insulator with high voltage shielding proposed by the present invention when in use;

In the figure: 1-1, GIL shell; 1-2, GIL conductor; 1-3, post insulator; 1, epoxy resin; 2, end grounding insert; 3, center insert assembly; 31, insert shield; 32, insert body; 33, connecting guide post; 34, arc surface; 35, annular convex edge; 36, through hole; 37, groove; 38, joint surface; 4, reinforcement ring; 41, connecting rod.

DETAILED DESCRIPTION

The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

Referring to Fig. 1-7, a GIL post insulator with high voltage shielding, a GIL post insulator with high voltage shielding, comprises an epoxy resin 1 arranged in an equilateral triangle shape, an end grounding insert 2 is arranged at each triangle of the epoxy resin 1, the end grounding insert 2 is made of metal copper, and the upper surface of the end grounding insert 2 is higher than the outer end of the epoxy resin 1, and a mounting hole is opened in the middle of the end grounding insert 2 for mounting a grounding plate, and a center insert assembly 3 is penetrated at each of the three edges of the epoxy resin 1, and the three center insert assemblies 3 are respectively located at the center of the three side lines;

The central insert assembly 3 includes an insert body 32 and an insert shielding member 31 sleeved in the middle of the insert body 32. The insert shielding member 31 is a thin-walled metal member. The insert body 32 and the insert shielding member 31 are fixedly connected by connecting guide posts 33. The number of connecting guide posts 33 is three to six, and the connecting guide posts 33 are evenly distributed around the center of the circle where the insert shielding member 31 is located. The insert body 32 and the insert shielding member 31 are combined into a whole by connecting guide posts 33, and a low electric field area is formed between the insert body 32 and the insert shielding member 31.

At the same time, the insert shielding member 31 includes a ring-shaped bonding surface 38, and a plurality of through holes 36 are provided on the bonding surface 38, so that when the post insulator is vacuum cast, the epoxy resin 1 and the insert shielding member 31 are tightly combined, and both ends of the bonding surface 38 are provided with multiple arc surfaces 34 upwardly, and the number of the arc surfaces 34 at each end is three to six, and the outer end of the arc surface composed of all the arc surfaces 34 is bent inward to form a middle-low and outer-high shape, and the starting point of the bonding between the epoxy resin 1 of the post insulator and the central insert assembly 3 is set in the low electric field area, ensuring that the post insulator will not cause flashover discharge due to the small air gap at the end of the bonding surface, thereby improving the insulation reliability of the GIL;

Secondly, the outer wall of the middle part of the insert body 32 protrudes upward to form an annular ridge 35, and the above-mentioned insert shielding member 31 is fixed on the annular ridge 35 through the connecting guide column 33, so that an annular area with a narrow middle and wide ends is formed between the insert shielding member 31 and the insert body 32. This annular area is the low electric field area.

After the pouring is completed, grooves 37 are provided at both ends where the epoxy resin 1 is combined with the central insert assembly 3. The width of the groove 37 is not less than 3 mm to avoid small gap discharge.

Furthermore, it also includes a positioning mechanism, which includes a reinforcement ring 4 installed at both ends of the insert body 32, and the reinforcement ring 4 is fixedly connected to the end of the insert shielding part 31 through a plurality of connecting rods 41. The number of the connecting rods 41 is three to ten, and the connecting rods 41 are evenly distributed around the center of the reinforcement ring 4, and the diameter of the connecting rod 41 at one end close to the insert shielding part 31 is smaller than that at the other end, which is convenient for truncation of the connecting rod 41.

A processing method for a GIL post insulator with a high-voltage shield, before vacuum casting the metal center insert assembly 3, the metal end grounding insert 2 and the epoxy resin 1, the bonding surface 38 of the insert shield 31 in the metal center insert assembly 3 is polished to remove the surface oil stains, improve the surface roughness, and further improve the bonding firmness between the epoxy resin 1 and the insert shield 31.

At the same time, before pouring, the two ends of the insert shielding part 31 are fixed by the positioning mechanism, and the curvature of the outer surface of the insert shielding part 31 is adjusted. The adjusted insert shielding part 31 is fixed during pouring by the positioning mechanisms at both ends to reduce the deformation of the insert shielding part 31 caused by high temperature during pouring. After the pouring is completed, the positioning mechanism is peeled off to form the insulator.

In this embodiment: by adding an insert shielding part 31 made of thin-walled metal on the outside of the insert body 32 and providing a plurality of small holes in the insert shielding part 31, the bonding strength between the epoxy resin 1 and the insert shielding part 31 can be improved, which is beneficial to the stress release during pouring. At the same time, by forming a low electric field area between the insert body 32 and the insert shielding part 31, the starting point of the bonding surface 38 between the epoxy resin 1 and the insert body 32 is set in the low electric field area, so that even if there is a small air gap at the end of the bonding surface 38, it will not cause flashover discharge of the support insulator, thereby improving the safety of the GIL during operation.

During installation, as shown in FIG. 7 , the post insulator 1 - 3 is installed in the GIL housing 1 - 1 , and the GIL conductor 1 - 2 is inserted into the insert body 32 , and the GIL conductor 1 - 2 is supported by the post insulator 1 - 3 .

The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims (10)

1. A GIL post insulator with high voltage shielding, comprising an epoxy resin (1) arranged in an equilateral triangle shape, characterized in that the epoxy resin (1) is provided with an end grounding insert (2) at each triangle, and a center insert assembly (3) is provided through each of the three edges of the epoxy resin (1); The central insert assembly (3) comprises an insert body (32) and an insert shielding member (31) sleeved on the middle of the insert body (32), the insert body (32) and the insert shielding member (31) being fixedly connected via a connecting guide column (33), and a low electric field region is formed between the insert body (32) and the insert shielding member (31); The insert shielding member (31) comprises a ring-shaped joint surface (38), a plurality of through holes (36) are arranged through the joint surface (38), and a plurality of arc surfaces (34) are arranged upward at both ends of the joint surface (38); The outer wall of the middle part of the insert body (32) protrudes upward to form an annular convex edge (35), and the insert shielding piece (31) is fixed on the annular convex edge (35) through a connecting guide column (33), so that an annular area with a narrow middle and wide ends is formed between the insert shielding piece (31) and the insert body (32). 2. A GIL post insulator with high voltage shielding according to claim 1, characterized in that the end grounding insert (2) is made of metal copper, and the upper surface of the end grounding insert (2) is higher than the outer end of the epoxy resin (1), and a mounting hole is opened in the middle of the end grounding insert (2). 3. A GIL post insulator with high voltage shielding according to claim 1, characterized in that the number of the connecting guide posts (33) is three to six, and the connecting guide posts (33) are evenly distributed around the center of the circle where the insert shielding member (31) is located. 4. A GIL post insulator with high-voltage shielding according to claim 3, characterized in that the insert shielding member (31) is a thin-walled metal member, and the number of arc surfaces (34) at each end of the insert shielding member (31) is three to six, and the outer end of the arc surface composed of all the arc surfaces (34) is bent inward. 5. A GIL post insulator with high voltage shielding according to claim 1, characterized in that grooves (37) are provided at both ends where the epoxy resin (1) is combined with the central insert assembly (3), and the width of the groove (37) is not less than 3 mm. 6. A GIL post insulator with high-voltage shielding according to claim 1, characterized in that it also includes a positioning mechanism, wherein the positioning mechanism includes reinforcement rings (4) installed at both ends of the insert body (32), and the reinforcement rings (4) are fixedly connected to the ends of the insert shielding member (31) through multiple connecting rods (41). 7. A GIL post insulator with high-voltage shielding according to claim 6, characterized in that the number of the connecting rods (41) is three to ten, and the connecting rods (41) are evenly distributed around the center of the reinforcement ring (4), and the diameter of the connecting rod (41) at one end close to the insert shielding part (31) is smaller than that at the other end. 8. A method for processing a GIL post insulator with high-voltage shielding according to claim 6, characterized in that before vacuum casting the metal center insert assembly (3), the metal end grounding insert (2) and the epoxy resin (1), the bonding surface (38) of the insert shielding part (31) in the metal center insert assembly (3) is polished to remove surface oil stains and improve surface roughness. 9. A method for processing a GIL post insulator with high voltage shielding according to claim 8, characterized in that before casting, the two ends of the insert shielding part (31) are fixed by a positioning mechanism to adjust the curvature of the outer surface of the insert shielding part (31). 10 . The method for processing a GIL post insulator with high voltage shielding according to claim 9 , characterized in that the positioning mechanism is stripped off after the casting is completed.