CN220754184U - Gas-insulated switchgear - Google Patents

Abstract

The application relates to a gas-insulated switchgear, including seal box and three station switch. The seal box is used for filling a gas insulating medium. The three-station switch comprises a grounding contact seat, an isolating contact seat, a connecting contact seat and a moving contact which are arranged in the sealing box, and the edges of the grounding contact seat, the isolating contact seat, the connecting contact seat and the moving contact are arc-shaped. Above-mentioned gas insulated switchgear, be located the earthing contact seat in the seal box, keep apart the contact seat, switch on the contact seat and the edge of moving contact is arc transition, can help improving the electric field, reduce the breakdown risk. Therefore, on the premise that the electric field distribution in the sealing box is more uniform, even when environment-friendly gas is used as a gas insulating medium, the filling air pressure is not required to be too high, and the leakage risk of the sealing box can be reduced while the environment protection is realized.

Description

Gas-insulated switchgear

Technical Field

The application relates to the technical field of electrical switching equipment, in particular to gas-insulated switching equipment.

Background

In the related art, the products with the voltage level of 72.5kV basically have a GIS structure and adopt SF ₆ The gas insulation or clean air insulation is used for ensuring sufficient insulativity, and the gas pressure in the shell is up to 0.5-0.7 MPa. However, SF ₆ The gas has stronger pollution to the atmosphere. Although clean air is an environment-friendly gas without pollution to the atmosphere, the air is not as insulating as SF ₆ The gas, in order to achieve a similar insulating effect, needs to be filled with a higher gas pressure. The high-pressure gas leakage risk is large, and the current offshore wind power project switching equipment is moving to the deep sea, so that the convenience and timeliness of maintenance and overhaul of the switching equipment are poor and the cost is high, once the gas leakage phenomenon occurs, the product cannot be used, the continuous operation of a wind power system is greatly influenced, and the reliability is poor.

Disclosure of Invention

In view of the above, it is necessary to provide a gas-insulated switchgear capable of using an environment-friendly gas as an insulating medium and contributing to a reduction in the gas pressure required for achieving the insulation purpose.

A gas-insulated switchgear apparatus, the gas-insulated switchgear apparatus comprising:

the sealed box is used for filling a gas insulating medium; and

The three-station switch comprises a grounding contact seat, an isolation contact seat, a connection contact seat and a moving contact which are arranged in the sealing box, wherein the edges of the grounding contact seat, the isolation contact seat, the connection contact seat and the moving contact are arc-shaped.

In one embodiment, the grounding contact base, the isolating contact base, the connecting contact base and the moving contact all comprise a peripheral surface, an end surface and a transitional cambered surface connecting the peripheral surface and the end surface.

In one embodiment, the arc of the transitional cambered surface is greater than 75 degrees and the radius is greater than 2mm.

In one embodiment, the gas-insulated switchgear further comprises a post insulator for fixing the isolating contact, and is configured with a shed in the middle.

In one embodiment, the gas insulated switchgear comprises two sets of the three-position switches; the gas insulated switchgear also includes a first outlet sleeve and a second outlet sleeve configured to be capable of forming an electrical connection through the two sets of three-position switches in an on position.

In one embodiment, the gas-insulated switchgear further comprises a vacuum circuit breaker, wherein the isolation contact of one group of three-position switches is connected with the first wire outlet sleeve, and the connection contact is connected with a lower wire outlet end of a solid-sealed polar pole of the vacuum circuit breaker; the isolation contact seat of the other group of three-station switches is communicated with the upper wire outlet end of the solid-sealed polar pole, and the connection contact seat is connected with the second wire outlet sleeve.

In one embodiment, the gas-insulated switchgear further comprises an outlet sleeve and a vacuum circuit breaker, wherein the outlet sleeve penetrates through the sealing box and forms a static seal with the sealing box, and the vacuum circuit breaker penetrates through the sealing box and forms a dynamic seal with the sealing box.

In one embodiment, the moving contact is at least partially sleeved in the isolation contact seat, and the moving contact is configured to be capable of moving along the axial direction of the moving contact; the isolated contact is configured with contact fingers at least at its inner ends.

In one embodiment, the three-position switch further comprises a three-position mechanism and a screw rod, wherein one end of the moving contact is provided with an internal thread, the moving contact is matched with the screw rod through the internal thread, and the three-position mechanism drives the moving contact to move through the screw rod.

In one embodiment, the gas-insulated medium comprises nitrogen, air, and SF ₆ One or more of the gases.

In one embodiment, the seal box comprises a box body and reinforcing ribs, wherein the reinforcing ribs are connected with the box body.

In one embodiment, the gas-insulated switchgear further comprises an instrument room, a mechanism room, a base frame and a cable room, wherein at least three layers of anticorrosive paint are sprayed on the surfaces of the instrument room, the mechanism room, the seal box, the base frame and the cable room.

Above-mentioned gas insulated switchgear, be located the earthing contact seat in the seal box, keep apart the contact seat, switch on the contact seat and the edge of moving contact is arc transition, can help improving the electric field, reduce the breakdown risk. Therefore, on the premise that the electric field distribution in the sealing box is more uniform, even when environment-friendly gas is used as a gas insulating medium, the filling air pressure is not required to be too high, and the leakage risk of the sealing box can be reduced while the environment protection is realized.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of a gas-insulated switchgear in an embodiment of the present application.

Fig. 2 is a schematic view of a part of the structure of the gas-insulated switchgear shown in fig. 1.

Fig. 3 is a schematic structural diagram of a second isolation contact in the gas-insulated switchgear shown in fig. 2.

Fig. 4 is a schematic cross-sectional view of the second isolated touch pad shown in fig. 3.

Fig. 5 is a schematic view of the structure of a lead screw in the gas-insulated switchgear shown in fig. 2.

Fig. 6 is a schematic view of the structure of the moving contact in the gas-insulated switchgear shown in fig. 2.

Fig. 7 is a schematic view of the structure of the post insulator in the gas-insulated switchgear shown in fig. 1.

Reference numerals illustrate: 100. a gas-insulated switchgear apparatus; 10. a seal box; 11. a case; 12. reinforcing ribs; 20. a three-station switch; 21. a grounding contact base; 22. isolating the contact base; 221. spring contact fingers; 222. a first isolation contact; 223. the second isolation contact seat; 2231. a boss; 22311. countersink; 22312. a second threaded hole; 2232. supporting a copper block; 23. the contact base is connected; 24. a moving contact; 241. an internal thread; 242. an orientation structure; 25. a three-station mechanism; 26. a screw rod; 261. an external thread; 30. an instrument room; 50. a mechanism chamber; 51. an aluminum plate; 52. a ground bus system; 53. a first separator; 60. a base frame; 70. a cable chamber; 71. a pressure relief plate; 72. a second separator; 80. a vacuum circuit breaker; 81. a mechanism panel; 82. a circuit breaker mechanism; 83. sealing the polar post; 90. a wire outlet sleeve; 91. a first outlet sleeve; 92. a second outlet sleeve; 922. a copper pad; 101. a lightning arrester; 102. a cable plug; 110. a post insulator; 111. an umbrella skirt; 112. a first threaded hole; r and the peripheral surface; D. an end face; H. and (5) a transitional cambered surface.

Detailed Description

In order to make the above objects, features and advantages of the present application more comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. This application is, however, susceptible of embodiment in many other forms than those described herein and similar modifications can be made by those skilled in the art without departing from the spirit of the application, and therefore the application is not to be limited to the specific embodiments disclosed below.

In the description of the present application, it should be understood that, if there are terms such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., these terms refer to the orientation or positional relationship based on the drawings, which are merely for convenience of description and simplification of description, and do not indicate or imply that the apparatus or element referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present application.

Furthermore, the term "and/or" is merely an association relation describing the association object, meaning that three relations may exist, e.g. a and/or B, may be represented: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship. The terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present application, the meaning of "plurality" is at least two, such as two, three, etc., unless explicitly defined otherwise.

In this application, unless specifically stated and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

In this application, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Referring to fig. 1 and 2, an embodiment of the present application provides a gas-insulated switchgear 100, which includes a sealed box 10 and a three-position switch 20. The sealing box 10 is used for filling a gas insulating medium. The three-position switch 20 includes a ground contact 21, an isolation contact 22, a contact-on contact 23, and a moving contact 24 provided in the sealed case 10, and edges of the ground contact 21, the isolation contact 22, the contact-on contact 23, and the moving contact 24 are configured in an arc shape.

The portions of the ground contact 21, the isolation contact 22, the contact-making contact 23, and the moving contact 24 configured in an arc shape include, but are not limited to, end edges, convex edges, concave edges, and the like. In other words, the intersecting and connected surfaces of the respective surfaces of the ground contact 21, the isolation contact 22, the contact-making contact 23, and the moving contact 24 form an arcuate transition at the connection (for example, at the connection of the end face D and the peripheral face R of the moving contact 24), and may be regarded as chamfering at the corners, and the contour surfaces of the ground contact 21, the isolation contact 22, the contact-making contact 23, and the moving contact 24 are continuous and conductive at all points.

The gas-insulated medium is preferably an environmentally friendly gas, and the movable contact 24 is capable of moving into communicating relation with different contact pads to switch the three-position switch 20 between a grounded position, an isolated position and an on position.

The gas insulated switchgear 100 may be used in high voltage scenarios and in particular for offshore wind power projects, its rated voltage may be greater than 12kV and in particular may be 27.5kV, 40.5kV or 72.5kV etc.

It will be appreciated that the gas insulated switchgear 100 may also include an instrument room 30, a mechanism room 50, a base frame 60, and a cable room 70 for its normal function. The mechanism chamber 50 is formed on the front side of the seal box 10, and the instrument chamber 30 is provided on the top of the mechanism chamber 50. A cable chamber 70 is formed at the rear side of the sealing box 10, and a pressure release plate 71 for releasing pressure is provided at the top. The seal box 10 is located between the cable compartment 70 and the mechanism compartment 50 and falls onto the base frame 60. All operating mechanisms of the gas insulated switchgear 100 are installed at the front side for uniform repair and maintenance, and are all installed by plating a high-quality steel plate with zinc-nickel alloy or zinc-chromium alloy. All outgoing line positions of the gas-insulated switchgear 100 are at the rear side, facilitating installation and maintenance of field cables.

In addition, the three-position switch 20 further includes a three-position mechanism 25, and the gas-insulated switchgear 100 may further include a vacuum interrupter 80 and an outlet sleeve 90. The three-position mechanism 25 and the vacuum interrupter 80 are provided in the mechanism chamber 50, and are respectively hung on the aluminum plate 51, and the aluminum plate 51 is fixed to the outside of the seal box 10. The three-position mechanism 25 is used for driving the movable contact 24 to move in position, so as to realize the conversion of the three-position switch 20 among a grounding position, an isolating position and an on position. The vacuum interrupter 80 includes a interrupter mechanism 82 located at the front, a mechanism panel 81 on the interrupter mechanism 82, and a solid-sealed pole 83 located at the rear, the mechanism panel 81 having operation buttons, position indicators, counter windows, and the like. The outlet sleeve 90 is used for connecting a lightning arrester 101 and a cable plug 102 which are positioned in the cable chamber 70, wherein the lightning arrester 101 is plugged into the rear part of the cable plug 102, and the cable plug 102 is plugged onto the outlet sleeve 90 and is used for connecting a cable.

In the gas-insulated switchgear 100, the edges of the ground contact seat 21, the isolation contact seat 22, the contact-on contact seat 23 and the moving contact 24 in the sealing box 10 are in arc transition, which can help to improve the electric field and reduce the breakdown risk. Therefore, on the premise that the electric field distribution in the seal box 10 is more uniform, even when the environment-friendly gas is used as the gas insulating medium, the filling air pressure is not required to be too high, and the leakage risk of the seal box 10 can be reduced while the environment protection is realized.

Referring to fig. 3, further, the ground contact 21, the isolation contact 22, the contact-on contact 23 and the moving contact 24 all include a peripheral surface R, an end surface D and a transitional arc surface H connecting the peripheral surface R and the end surface D.

The transitional cambered surface H is an edge which is constructed to be arc-shaped. Therefore, the transition cambered surface H can well eliminate the possible interruption at the joint of the circumferential surface R and the end surface D, and improve the electric field.

Further, the radian of the transitional cambered surface H is more than 75 degrees, and the radius is more than 2mm. The radian of the transitional cambered surface H can be 90 degrees and the radius is 2mm.

Thus, smooth transition is realized between the peripheral surface R and the end surface D, and the electric field distribution around the peripheral surface R can be more uniform, so that the possibility of breakdown discharge is reduced.

In particular, the gas-insulating medium comprises nitrogen, air and SF ₆ One or more of them. Preferably, the sealing box 10 is filled with nitrogen, dry air and SF ₆ The gas is nitrogen or dry air, the filled gas insulating medium is micro-positive pressure gas, and the air pressure is not more than 0.25MPa.

In some embodiments, the seal box 10 includes a box body 11 and a reinforcing rib 12, the reinforcing rib 12 connecting the box body 11.

Wherein, the box 11 adopts a rectangular box 11 which is made of nonmagnetic stainless steel plates by laser cutting and laser welding, and the reinforcing ribs 12 can also be connected with the box 11 by welding. The reinforcing ribs 12 may be provided on the surface of the case 11, and particularly on the inner surface of the case 11, and the case 11 is provided with the reinforcing ribs 12 at least at the top.

It will be appreciated that the case 11 of the seal case 10 may be further prevented from being manufactured by casting, stamping, etc. integrally formed, and the reinforcing rib 12 may be located at the top inside the case 11 and may be integrally formed with the case 11, which is not particularly limited herein.

The reinforcing ribs 12 can enhance the strength of the case 11, reduce the possibility of deformation thereof, and improve the reliability of the seal case 10.

Further, the surfaces of the three-position mechanism 25 and the breaker mechanism 82 of the vacuum breaker 80 are plated with zinc-nickel alloy or zinc-chromium alloy, at least three layers of anticorrosive paint (at least three layers of anticorrosive paint including bottom layer, middle layer and surface layer) are sprayed on the surfaces of the instrument room 30, the mechanism room 50, the seal box 10, the cable chamber 70, and the connection of the instrument room 30, the mechanism room 50, the seal box 10, the base frame 60 and the cable chamber 70 is bolted by welding or bolts.

Plating zinc-nickel alloy or zinc-chromium alloy and spraying multilayer anticorrosive paint can enhance the corrosion resistance of the gas-insulated switchgear 100, and is suitable for wet and multi-salt environments working at sea. The instrument room 30, the mechanism room 50, the seal box 10, the base frame 60, and the cable room 70 can be stably connected by welding or bolting, and the shock resistance of the gas-insulated switchgear 100 can be enhanced.

Referring to fig. 4 to 6, in some embodiments, the moving contact 24 is at least partially sleeved in the isolating contact 22, and the ground contact 21 and the contact-on contact 23 are respectively located at two axial ends of the moving contact 24. The movable contact 24 is configured to be movable in the axial direction thereof, and to be movable to be spaced apart from the ground contact 21 and the contact-making contact 23, to be in contact with the ground contact 21, and to be in contact with the contact-making contact 23, respectively. It is easy to see that when the moving contact 24 moves to contact the ground contact 21 or the contact-making contact 23, the ground contact 21 or the contact-making contact 23 contacting the moving contact is connected electrically.

When the moving contact 24 is completely hidden in the isolating contact seat 22, the three-position switch 20 is in an isolating position, when the moving contact 24 is communicated with the grounding contact seat 21 and the isolating contact seat 22, the three-position switch 20 is in a grounding position, and when the moving contact 24 is communicated with the connecting contact seat 23 and the isolating contact seat 22, the three-position switch 20 is in a connecting position. The ground contact seat 21 is installed on aluminum plate 51, and aluminum plate 51 links to each other with ground busbar system 52, effectively realizes the ground continuity of whole switchgear.

The movable contact 24 can form different connection modes among the grounding contact seat 21, the isolating contact seat 22 and the connecting contact seat 23 by moving to different positions, so that the three-position switch 20 is respectively positioned at the grounding position, the isolating position and the connecting position.

Further, the isolating contact 22 is configured with contact fingers at least at its inner ends, and the contact fingers may be spring contact fingers 221.

The moving contact 24 remains at least partially positioned within the isolation contact 22 during movement. The contact fingers are constructed in the two ends of the isolation contact seat 22, so that the movable contact 24 can form good contact with the contact fingers when the movable contact is at different positions, and the reliable connection of the electric main circuit is ensured.

Further, the three-position switch 20 further comprises a screw rod 26, one end of the movable contact 24 is provided with an internal thread 241, the movable contact 24 is matched with the screw rod 26 through the internal thread 241, and the three-position mechanism 25 drives the movable contact 24 to move through the screw rod 26.

The screw rod 26 is provided with an external thread 261, and the three-station mechanism 25 is in transmission connection with the moving contact 24 through the screw rod 26 and drives the moving contact 24 to axially move along by driving the screw rod 26 to rotate.

The screw rod 26 can be used for driving the movable contact 24, and also has a certain fixed connection function on the movable contact 24, and the driving mode is stable.

In addition, an orientation structure 242 may be configured between the moving contact 24 and the isolating contact base 22 to ensure that the moving contact 24 is more stable during the driven movement.

In some embodiments, the outlet sleeve 90 is threaded through the seal case 10 and forms a static seal with the seal case 10, and the vacuum interrupter 80 is threaded through the seal case 10 and forms a dynamic seal with the seal case 10.

The outlet sleeve 90 is inserted through the casing 11 of the sealed box 10, partially positioned in the cable chamber 70 to connect the lightning arrester 101 and the cable plug 102, and partially positioned in the sealed box 10 to connect the contact base 23. And a sealing ring made of ethylene propylene diene monomer can be adopted between the outlet sleeve 90 and the box 11 to realize static sealing. In addition, the aluminum plate 51 and the case 11 may form a static seal in the same manner.

The vacuum interrupter 80 is partially located in the mechanism compartment 50 (e.g., interrupter mechanism 82), partially located in the sealed housing 10 (e.g., solid sealed pole 83), and may be dynamically sealed to the housing 11 by metal welding the bellows.

Similarly, the three-position switch 20 is also partially disposed within the seal box 10 (e.g., the ground contact 21) in a portion of the mechanism chamber 50 (e.g., the three-position mechanism 25). Therefore, the three-position switch 20 and the seal box 10 are in dynamic seal, and dynamic seal can be realized through the magnetic fluid assembly.

Similar to the outlet sleeve 90, the aluminum plate 51 is structurally fixed and does not require action, and thus can form a static seal with the seal box 10. In the case of the vacuum circuit breaker 80 and the three-position switch 20, which are constructed in such a manner that there is a transmission relationship between the inside and the outside, it is necessary to maintain the transmission capability while achieving sealing by dynamic sealing. Whether static seal or dynamic seal, the sealing performance of the seal box 10 can be enhanced, and the possibility of leakage is reduced.

Referring to fig. 7, in some embodiments, the gas-insulated switchgear 100 further includes a post insulator 110, where the post insulator 110 is used to fix the isolation contact 22, and has a shed 111 formed in the middle.

The post insulator 110 is made of an insulating material, and a central portion thereof, i.e., a region between both ends, is configured with an annular protrusion or groove, forming an umbrella skirt 111 structure. The post insulator 110 is configured with a first threaded hole 112 at both ends thereof, one end thereof being connected to the isolating contact 22 and the other end thereof being connectable to the reinforcing rib 12.

The post insulator 110 with the umbrella skirt 111 is fixed to isolate the contact base 22, so that the electric main loop can have enough creepage distance to the ground when the electric main loop is provided with high voltage.

In some embodiments, the gas-insulated switchgear 100 further includes a grading ring (not shown) sleeved on at least one of the ground contact 21, the isolation contact 22, the contact-on contact 23, and the moving contact 24 for improving the electric field.

In some embodiments, the gas-insulated switchgear 100 includes two sets of three-position switches 20. The outlet sleeve 90 comprises a first outlet sleeve 91 and a second outlet sleeve 92, the first outlet sleeve 91 and the second outlet sleeve 92 being configured to be able to form an electrical connection through the two sets of three-position switches 20 in the on position.

It will be appreciated that the ground contact 21, isolation contact 22, on contact 23 and moving contact 24 of the two sets of three-position switches 20 are all located within the sealed box 10. The first wire outlet sleeve 91 and the second wire outlet sleeve 92 are respectively used for two groups of cable connection, wherein the first wire outlet sleeve 91 can be connected with the high-voltage side output end of the fan tower transformer through a cable, and the second wire outlet sleeve 92 can be connected with the current collecting circuit submarine cable through a cable connection. In this way, when the first outlet sleeve 91 and the second outlet sleeve 92 are electrically connected by the two sets of three-position switches 20 that are simultaneously in the on position, a communication circuit is formed in the gas-insulated switchgear 100.

The two sets of three-position switches 20 are arranged at intervals in the up-down direction, and the first outlet sleeve 91 and the second outlet sleeve 92 are also arranged at intervals in the up-down direction. A first partition 53 and a second partition 72 are also provided in the mechanism chamber 50 and the cable chamber 70, respectively, the first partition 53 being for partitioning the mechanism chamber 50 into upper and lower portions, respectively, in which the two three-position mechanisms 25 of the two sets of three-position switches 20 are located. The second partition 72 is used to divide the cable compartment 70 into upper and lower portions, and the first outlet sleeve 91 and the second outlet sleeve 92 are located at the lower and upper portions, respectively.

Thus, the two groups of three-position switches 20 integrally share one sealed box 10, so that a one-in one-out power supply scheme can be formed through one sealed box 10, which is beneficial to reducing the volume of the gas-insulated switchgear 100, reducing the occupied area and reducing the construction cost.

Further, in the two sets of three-position switches 20, the isolation contact 22 of one set of three-position switches 20 is connected to the first wire outlet sleeve 91, the connection contact 23 is connected to the lower wire outlet end of the solid sealed pole 83 of the vacuum circuit breaker 80, the connection contact 23 of the set of three-position switches 20 can be fixed to the box 11 through the post insulator 110, and meanwhile, in consideration of the space between the positions, the isolation contact 22 and the connection contact 23 can be connected to the first wire outlet sleeve 91 and the lower wire outlet end of the solid sealed pole 83 through connecting buses respectively. The isolation contact seat 22 of the other group of three-position switch 20 is communicated with the upper outlet end of the solid-sealed polar pole 83, and the connection contact seat 23 is connected with the second outlet sleeve 92. The connection contact base 23 connected to the second outlet sleeve 92 may be directly connected to the second outlet sleeve 92 through the copper pad 922 without using a connection bus, which is helpful for reducing the usage amount of the connection bus.

Thus, when the two groups of three-position switches 20 are all in the on position, that is, the moving contacts 24 are all moved to be communicated with the respective isolation contact seats 22 and the on contact seat 23, one end of the first wire outlet sleeve 91 is connected with the high-voltage side output end of the fan tower transformer through a cable, the other end of the first wire outlet sleeve is connected with the isolation contact seat 22 of the group of three-position switches 20, and the isolation contact seat 22 is connected with the on contact seat 23 through the moving contacts 24, so that the conduction of a wire outlet loop is formed. The isolation contact seat 22 of the other group of three-position switch 20 is connected with the connection contact seat 23 through the movable contact 24, the connection contact seat 23 is connected with the second outgoing line sleeve 92 through the copper cushion block 922, and the second outgoing line sleeve 92 is connected with the current collecting line submarine cable through a cable, so that the conduction of an incoming line loop is formed. The vacuum circuit breaker 80 is switched on, and the wire outlet loop and the wire inlet loop are communicated through the lower wire outlet end and the upper wire outlet end of the solid-sealed pole 83, so that a one-in one-out power supply scheme is formed.

Thus, the vacuum circuit breaker 80 is closed to form a conduction loop: the first outlet sleeve 91-the isolation contact 22 of one group of three-position switches 20-the moving contact 24-the contact-on contact 23-the solid-sealed pole 83-the isolation contact 22 of the other group of three-position switches 20-the moving contact 24-the contact-on contact 23-the second outlet sleeve 92.

Further, the isolation contact 22 connected to the first wire outlet sleeve 91 through a cable is a first isolation contact 222, and the isolation contact 22 connected to the upper wire outlet end of the solid-sealed pole 83 is a second isolation contact 223. Rectangular bosses 2231 are arranged on the upper side and the lower side of the second isolation contact seat 223, the upper boss 2231 is connected with the post insulator 110, the lower boss 2231 is connected with a supporting copper block 2232, the supporting copper block 2232 is connected with the solid-sealed pole 83, namely, the supporting copper block 2232 is arranged between the second isolation contact seat 223 and the solid-sealed pole 83, and the two are electrically connected. The boss 2231 of the second isolation contact 223 connected to the post insulator 110 is provided with a counter bore 22311, and is connected to the post insulator 110 through the counter bore 22311, and the post insulator 110 is connected to the reinforcing rib 12 at the inner top of the case 11. The boss 2231 of the second isolation contact 223 coupled to the supporting copper block 2232 is configured with a second screw hole 22312 and coupled to the supporting copper block 2232 through a second screw hole 22312.

In the gas-insulated switchgear 100, the inside of the sealed case 10 is filled with an environment-friendly gas having a gas pressure of not more than 0.25MPa. Meanwhile, the gas-insulated switchgear 100 is integrally provided with two groups of three-position switches 20, the grounding contact seat 21, the isolation contact seat 22, the connection contact seat 23 and the moving contact 24 of the two groups of three-position switches 20 are all located in the same sealing box 10, the edges of the grounding contact seat 21, the isolation contact seat 22, the connection contact seat 23 and the moving contact 24 are all in circular arc transition, and the pillar insulator 110 for fixing the isolation contact seat 22 is provided with umbrella skirts 111. The grounding contact seat 21, the isolation contact seat 22, the connection contact seat 23 and the moving contact 24 with arc edges can reduce the tip structure, effectively improve the electric field and the breakdown voltage, and meanwhile, the umbrella skirt 111 of the post insulator 110 can increase the creepage distance. Thus, the electric field distribution in the sealing box 10 is more uniform, the environment-friendly gas with the filling air pressure not more than 0.25MPa can meet the insulation requirement, and the leakage risk of the sealing box 10 can be reduced due to the reduction of the filling air pressure. The gas-insulated switchgear 100 is integrally provided with two groups of three-position switches 20, and a power supply scheme of one inlet and one outlet can be realized through one sealed box 10, so that the volume of the gas-insulated switchgear 100 is reduced, the occupied area is reduced, and the construction cost is reduced. In addition, the operating mechanism is formed by adopting high-quality steel plates to be plated by zinc-nickel alloy or zinc-chromium alloy, the surfaces of the structures are sprayed with three layers of anticorrosive paint of the bottom, middle and surface, and the structures are welded or reliably bolted, so that the requirements on the performance of marine corrosion resistance and earthquake resistance can be effectively met.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples only represent a few embodiments of the present application, which are described in more detail and are not to be construed as limiting the scope of the claims. It should be noted that it would be apparent to those skilled in the art that various modifications and improvements could be made without departing from the spirit of the present application, which would be within the scope of the present application. Accordingly, the scope of protection of the present application is to be determined by the claims appended hereto.

Claims (12)

1. A gas-insulated switchgear, characterized in that it comprises:

a seal box (10) for filling with a gas insulating medium; and

The three-position switch (20) comprises a grounding contact seat (21), an isolation contact seat (22), a connection contact seat (23) and a moving contact (24) which are arranged in the sealing box (10), wherein the edges of the grounding contact seat (21), the isolation contact seat (22), the connection contact seat (23) and the moving contact (24) are arc-shaped.

2. The gas-insulated switchgear device according to claim 1, characterized in that the ground contact (21), the isolating contact (22), the contact-on contact (23) and the moving contact (24) each comprise a circumferential surface (R), an end surface (D) and a transitional arc surface (H) connecting the circumferential surface (R) and the end surface (D).

3. A gas-insulated switchgear according to claim 2, characterized in that the arc of the transition arc (H) is greater than 75 °, and the radius is greater than 2mm.

4. The gas-insulated switchgear device according to claim 1, characterized in that it further comprises a post insulator (110), which post insulator (110) is used for fixing the isolating contact (22) and is configured with a shed (111) in the middle.

5. Gas-insulated switchgear according to claim 1, characterized in that it comprises two sets of said three-position switches (20); the gas-insulated switchgear further comprises a first outlet bushing (91) and a second outlet bushing (92), the first outlet bushing (91) and the second outlet bushing (92) being configured to be able to form an electrical connection by means of two sets of the three-position switches (20) in an on position.

6. The gas-insulated switchgear according to claim 5, characterized in that it further comprises a vacuum circuit breaker (80), wherein, of two sets of said three-position switches (20), the isolating contact (22) of one set of said three-position switches (20) is connected to the first outlet bushing (91), and the on contact (23) is connected to the lower outlet end of the solid-sealed pole (83) of said vacuum circuit breaker (80); the isolation contact seat (22) of the other group of three-position switches (20) is communicated with the upper wire outlet end of the solid-sealed polar pole (83), and the connection contact seat (23) is connected with the second wire outlet sleeve (92).

7. The gas-insulated switchgear according to claim 1, characterized in that it further comprises an outlet bushing (90) and a vacuum circuit breaker (80), the outlet bushing (90) being arranged through the sealing box (10) and forming a static seal with the sealing box (10), the vacuum circuit breaker (80) being arranged through the sealing box (10) and forming a dynamic seal with the sealing box (10).

8. The gas-insulated switchgear device according to claim 1, characterized in that the moving contact (24) is at least partially housed inside the isolating contact seat (22), the moving contact (24) being configured to be able to move axially along itself; the isolating contact (22) is provided with contact fingers at least at its inner ends.

9. The gas-insulated switchgear device according to claim 8, wherein the three-position switch (20) further comprises a three-position mechanism (25) and a screw (26), wherein one end of the moving contact (24) is provided with an internal thread (241) and is matched with the screw (26) through the internal thread (241), and the three-position mechanism (25) drives the moving contact (24) to move through the screw (26).

10. The gas-insulated switchgear as claimed in claim 1, wherein the gas-insulated medium comprises nitrogen, air and SF ₆ One or more of the gases.

11. The gas-insulated switchgear device according to claim 1, characterized in that the sealed box (10) comprises a box body (11) and a reinforcing rib (12), the reinforcing rib (12) being connected to the box body (11).

12. The gas-insulated switchgear according to claim 1, characterized in that it further comprises an instrument room (30), a mechanism room (50), a base frame (60) and a cable room (70), the surfaces of the instrument room (30), the mechanism room (50), the seal box (10), the base frame (60) and the cable room (70) being sprayed with at least three layers of anticorrosive paint.