CN108321692A - Entrance bushing - Google Patents

Abstract

The invention relates to an incoming line bushing. A connecting flange is arranged on the incoming line casing, which is fixed on a solid insulating casing through flange connection, and a vacuum interrupter is arranged in the incoming line casing of the incoming line casing. And through the incoming line sleeves are fixed on the solid insulating shell in an orderly manner, which solves the problem that the existing split component connection technology cannot ensure the electrical performance requirements of the vacuum interrupter, that is, realizes the integration of the original solid insulating shell The vacuum interrupter is detached, which realizes the orderly control of the electric field and avoids the problem of partial discharge.

Description

Inlet bushing

technical field

The invention belongs to the technical field of high-voltage power distribution equipment, and in particular relates to a split-type incoming line bushing for a solid-insulated ring network cabinet.

Background technique

Most of the traditional ring network cabinets are gas insulated ring network cabinets. SF6 gas is used as the insulation or breaking medium of the high-voltage live part. Since SF6 gas will decompose and produce toxic gas after it is disconnected, and it is easy to leak, the sealing requirements for the box are high and the processing technology is complicated, which makes the maintenance and testing of the gas-insulated ring network cabinet more complicated, and regular leak detection and gas replenishment are required. In addition, according to the "Kyoto Protocol", as the insulation or breaking medium of the gas-insulated ring main unit, SF6 gas is clearly listed as one of the greenhouse gases, and its use is required to be reduced.

In view of this problem, the Chinese patent of publication (announcement) No. CN202797738U provides a solid insulation vacuum ring network cabinet, which is characterized in that the incoming line vacuum switch unit in the incoming line ring network cabinet and the outgoing line vacuum switch in the outgoing line ring network cabinet The unit is installed on the cabinet body through screws, and the silicone rubber dry-type busbar is respectively installed on the busbar plugs of the incoming line vacuum switch unit and the outgoing line vacuum switch unit through screws.

Although the prior art realizes the fully enclosed solid insulated vacuum switch, and the electrified body is poured or installed in the epoxy resin, it has the following technical problems: in order to realize the electrical safety performance of the vacuum interrupter, it is impossible to realize the vacuum switch in the prior art. The splitting of the interrupter and the solid insulating shell, that is, the solid insulating shell is embedded with a vacuum interrupter. However, this kind of embedded structure easily leads to uneven electric field in the solid insulating shell, and the partial discharge is difficult to control.

However, in actual production, the three-phase one-piece insulated housing switch usually uses a vacuum interrupter to be cast together with the housing. This method has higher requirements for APG production. The problem that the entire switch housing is scrapped; at the same time, the switch housing after the vacuum interrupter is pre-installed increases the weight of the vacuum interrupter itself, which causes the housing to be easily deformed during post-curing and finalization, causing the moving end of the interrupter to be vertical Offset, it is necessary to make a large number of shaping tools for shaping.

Contents of the invention

The invention aims to provide a wire inlet bushing to solve the problem that the existing wire inlet bushing has poor electrical performance when connected to a solid insulating casing, and the vacuum interrupter must be built in the solid insulating casing.

The specific scheme is as follows: the incoming line casing includes the incoming line casing, and the incoming line conductor and the vacuum interrupter are arranged in the incoming line casing, and the incoming line conductor is electrically connected to the vacuum interrupter; A connection through hole is also provided at a position corresponding to the vacuum interrupter; around the connection through hole, a connection flange is also provided on the incoming line housing.

Further, the incoming line conductor and the vacuum interrupter are respectively arranged at the upper and lower ends of the incoming line casing; the connection through hole is arranged at the lower end of the incoming line conductor to form a through hole, and the incoming line casing The upper end of the corresponding to the position of the incoming conductor is also provided with an upper through hole.

Further, the upper end of the incoming conductor protrudes out of the incoming housing through the upper through hole, the lower end of the incoming conductor is inserted into the upper end of the vacuum interrupter, and the lower end of the vacuum interrupter is set in the The inside of the wire inlet housing is right at the position of the lower through hole.

Further, a protective cover is provided on the vacuum interrupter, and the front and rear ends of the vacuum interrupter respectively protrude from the protective cover.

Further, on the incoming line housing, the central area of the connection flange protrudes outwards to form a projection with a narrowed section, and the connection through hole is provided at the top of the projection.

Further, around the bottom end of the protrusion, the connecting flange is provided with a plurality of bolt installation holes, and the protrusion is a circular platform.

Further, around the wall surface of the protrusion, the protrusion is also coated with sealing and insulating silica gel.

Further, the wire-in conductor is a copper rod, and the wire-in housing is integrally molded with epoxy resin.

In the wire inlet sleeve of this embodiment, a connection flange is arranged on the wire inlet housing, and is fixed on the solid insulating housing through a flange connection to realize structural connection. The electrical isolation performance of the same technical requirements as the one-piece solid insulating shell solves the problem that the existing split component connection technology cannot ensure the electrical performance requirements of the vacuum interrupter, that is, it realizes the vacuum arc extinguishing in the original solid insulating shell The chamber is disassembled, and the vacuum interrupter is set in the incoming line housing of the incoming line bushing, and is fixed on the solid insulating shell in an orderly manner through the incoming line bushing, which realizes the orderly control of the electric field and avoids local discharge problem; at the same time, the separate casting molding of the shell is realized, the process is simple, and the single vacuum interrupter is packaged, the industrial yield is better, and the deformation problem of the qualitative process is avoided. The flange connection method achieves the same air tightness and electrical performance requirements as the original integrated shell, breaks the limitations of the existing conventional technical ideas, and solves the difficulty of controlling the electric field in the existing solid insulating shell, which is easy to be partially discharged. Moreover, it is difficult to process and form, and the size and structure precision are not high.

Description of drawings

Fig. 1 shows a schematic structural diagram of an angle-one embodiment of the present invention;

Fig. 2 shows a schematic diagram of the structure of angle 2 in Fig. 1;

Fig. 3 shows the front view of Fig. 1;

FIG. 4 shows a cross-sectional view of the F-F section of FIG. 3 .

Detailed ways

To further illustrate the various embodiments, the present invention is provided with accompanying drawings. These drawings are a part of the disclosure of the present invention, which are mainly used to illustrate the embodiments, and can be combined with related descriptions in the specification to explain the operating principles of the embodiments. With reference to these contents, those skilled in the art should understand other possible implementations and advantages of the present invention. Components in the figures are not drawn to scale, and similar component symbols are generally used to denote similar components.

The present invention will be further described in conjunction with the accompanying drawings and specific embodiments.

As shown in FIG. 1 to FIG. 4 , the wire inlet bushing of this embodiment includes a wire inlet housing 1 , a wire inlet conductor 2 and a vacuum interrupter 3 :

In this embodiment, the incoming conductor 2 is a cylindrical copper rod, the upper end of which is provided with a threaded socket, and the lower end is provided with a cylindrical plug, and is inserted into the upper end of the vacuum interrupter 3 through the plug, The electrical connection between the incoming conductor 2 and the vacuum interrupter 3 is realized.

The incoming line conductor 2 and the vacuum interrupter 3 are set in the incoming line housing 1, specifically: the vacuum interrupter 3 is provided with a protective cover 31 of insulating and heat-resistant material, and the protective cover 31 is The two ends of the cylinder are connected, so that the front and rear ends of the vacuum interrupter 3 protrude from the protective cover 31 respectively; After the incoming line conductor 2 and the vacuum interrupter 3 are electrically connected, the forming of the incoming line casing 1 is realized, and the incoming line conductor 2 and the vacuum interrupter 3 are respectively arranged on the upper and lower sides of the incoming line casing 1 ends.

In order to realize the connection of the incoming line sleeve to the external circuit, the upper and lower ends of the incoming line casing 1 are respectively provided with an upper through hole and a lower through hole, and the upper end of the incoming line conductor 2 protrudes out of the incoming line through the upper through hole. Housing 1, and the lower through hole is set at the position facing the lower end of the vacuum interrupter 3, and leads to the vacuum interrupter 3, so that the external conductor can be inserted into the vacuum interrupter through the lower through hole. The lower end of the arc extinguishing chamber 3.

In this embodiment, the lower through hole is the connection through hole corresponding to the vacuum interrupter 3, in order to realize the electrical sealing effect after the connection, around the connection through hole, the incoming line housing 1 is also provided with a connection method Lan 10:

The main body of the connecting flange 10 is a cuboid plate, and each of its four corners is provided with a bolt mounting hole for bolts to pass through. The central part of the connecting flange 10 protrudes outward, that is, downward It protrudes and forms a bump 11 with a shrinking section. Preferably, the bump is a circular platform, and the bolt installation holes are arranged around the bottom end of the bump 11, so that after installation, the bump 11 can be inserted into the corresponding In the fixed structure (not shown in the figure, such as a solid insulating shell), and the end face of the connecting flange 10 is in contact with the opening of the fixed structure to ensure the depth of insertion.

The connection through hole, that is, the lower through hole, is located at the top of the bump 11, that is, at a position away from the end face of the connecting flange 10; It is also coated with sealing and insulating silica gel (not shown in the figure), preferably, it is sprayed or poured and molded as sealing insulating silica gel.

The working principle of this embodiment is:

Another connecting flange adapted to the connecting flange 10 is provided on the solid insulating housing, and then the connecting flange 10 is installed on the solid insulating housing, and the side wall surface of the protrusion 11 is in contact with the solid body. The inner wall surface of the connecting flange on the insulating shell is then fixed by bolts to realize electrical isolation and water-air sealing; at the same time, the end face of the connecting flange 10 is in contact with the solid insulating shell to ensure that the lower through hole is inserted into the solid insulating shell The depth in the body achieves a better electrical isolation effect.

Although the present invention has been particularly shown and described in conjunction with preferred embodiments, it will be understood by those skilled in the art that changes in form and details may be made to the present invention without departing from the spirit and scope of the invention as defined by the appended claims. Making various changes is within the protection scope of the present invention.

Claims (8)

1. The inlet bushing is characterized in that: It includes an incoming line housing, which is provided with an incoming line conductor and a vacuum interrupter, and the incoming line conductor is electrically connected to the vacuum interrupter; A connection through hole is also provided on the inlet housing at a position corresponding to the vacuum interrupter; Surrounding the connection through hole, a connection flange is also provided on the line inlet housing. 2. The wire inlet bushing according to claim 1, characterized in that: the wire inlet conductor and the vacuum interrupter are respectively arranged at the upper and lower ends of the wire inlet housing; the connection through hole is arranged at the wire inlet The lower end of the conductor is to form a lower through hole, and the upper end of the incoming line housing is also provided with an upper through hole corresponding to the position of the incoming line conductor. 3. The wire inlet bushing according to claim 2, characterized in that: the upper end of the wire inlet conductor protrudes out of the wire inlet casing through the upper through hole, and the lower end of the wire inlet conductor is inserted into the vacuum extinguisher. The upper end of the arc chamber and the lower end of the vacuum interrupter are arranged in the inner part of the incoming line housing at a position facing the lower through hole. 4 . The cable inlet bushing according to claim 1 , wherein a protective cover is provided on the vacuum interrupter, and the front and rear ends of the vacuum interrupter respectively protrude from the protective cover. 5. The wire inlet bushing according to claim 1, characterized in that: on the wire inlet housing, the area in the middle of the connection flange protrudes outwards to form a bump with a shrinking section, and the connection through hole set on the top of the bump. 6 . The cable inlet bushing according to claim 5 , wherein around the bottom end of the protrusion, the connecting flange is provided with a plurality of bolt mounting holes, and the protrusion is a circular platform. 7 . 7 . The wire inlet bushing according to claim 5 , characterized in that: the wall surrounding the protrusion is coated with sealing and insulating silica gel. 7 . 8. The wire inlet bushing according to claim 1, characterized in that: the wire inlet conductor is a copper rod, and the wire inlet housing is formed integrally with epoxy resin.