High-current-carrying 126kV vacuum circuit breaker static contact transmission structure

Abstract

The invention discloses a high-current-carrying 126kV vacuum circuit breaker static contact transmission structure, and relates to the technical field of vacuum circuit breakers, the high-current-carrying 126kV vacuum circuit breaker static contact transmission structure comprises a sleeve and a vacuum arc-extinguishing chamber, the top of the sleeve is provided with an upper wiring board, the upper wiring board is provided with an upper cover plate, the bottom of the upper wiring board is fixedly connected with a static contact seat, the top of the vacuum arc-extinguishing chamber is provided with a metal conductor, and the metal conductor is fixedly connected with the static contact seat. The metal conductor is slidably connected to the inner cavity of the static contact seat, the side surface of the metal conductor is provided with a plurality of spring contacts, the metal conductor is fixedly connected with a heat conduction rod, the top of the heat conduction rod is provided with a grounding bar, and the grounding bar is slidably connected to the inner cavity of the upper wiring board. A cavity among the vacuum arc-extinguishing chamber, the metal conductor, the spring contact, the static contact seat and the sleeve is filled with a gas insulating medium, current can flow through a static conducting rod at the upper end of the vacuum arc-extinguishing chamber, the metal conductor, the spring contact and the static contact seat and finally flows out through the upper wiring board, high current-carrying capacity is achieved, and meanwhile when the vacuum arc-extinguishing chamber is closed, the vacuum arc-extinguishing chamber is closed. Closing bounce of the vacuum circuit breaker can be effectively inhibited through the buffer assembly.

Description

Technical Field

[0001] The invention relates to the technical field of vacuum circuit breakers, in particular to a static contact transmission structure of a high current-carrying 126kV vacuum circuit breaker. Background Art

[0002] The vacuum circuit breaker is named because its arc extinguishing medium and the insulating medium of the contact gap after arc extinguishing are both high vacuum; it has the advantages of small size, light weight, suitable for frequent operation, and arc extinguishing without maintenance, and is widely used in distribution networks. The vacuum circuit breaker is an indoor power distribution device in 3~10kV, 50Hz three-phase AC system. It can be used for protection and control of electrical equipment in industrial and mining enterprises, power plants, and substations. It is particularly suitable for use in places that require oil-free, less maintenance and frequent operation. The circuit breaker can be configured in a central cabinet, double-layer cabinet, or fixed cabinet to control and protect high-voltage electrical equipment.

[0003] High-voltage vacuum circuit breakers have outstanding capabilities in short-circuit current breaking, but at voltage levels of 126kV and above, the size and mass of the moving contact of the vacuum interrupter are greatly increased, and the vacuum has good thermal insulation, resulting in weak current-carrying capacity of the vacuum circuit breaker. At the same time, during the closing process of the vacuum circuit breaker, the moving contact of the vacuum interrupter collides with the static contact at high speed, accompanied by a series of repeated bounce processes, namely the closing bounce phenomenon. The longer the closing bounce time, the longer the closing pre-breakdown time will be, and the ablation time will also be longer. The surface quality of the contact will decrease due to long-term ablation, which will reduce the breaking capacity and electrical life of the vacuum interrupter. This will affect the service life of the vacuum circuit breaker. Summary of the invention

[0004] In order to overcome the defects of weak current carrying capacity and closing bounce in the prior art, the present invention provides a high current carrying 126kV vacuum circuit breaker static contact transmission structure.

[0005] The technical solution adopted by the present invention to solve its technical problems is: a high-current 126kV vacuum circuit breaker static contact transmission structure, including a bushing and a vacuum interrupter arranged in the bushing, an upper wiring board is arranged on the top of the bushing, an upper cover is installed on the upper wiring board, a static contact seat is fixedly connected to the bottom of the upper wiring board, the static contact seat is arranged inside the bushing, a metal conductor is arranged on the top of the vacuum interrupter, the metal conductor is slidably connected to the inner cavity of the static contact seat, a plurality of spring contacts are arranged on the side of the metal conductor, the metal conductor is fixedly connected to a heat conducting rod, a grounding bar is arranged on the top of the heat conducting rod, the grounding bar is slidably connected to the inner cavity of the upper wiring board, and a gas insulating medium is filled in the chamber between the vacuum interrupter, the metal conductor, the spring contact, the static contact seat and the bushing.

[0006] As a further improvement of the present invention, a guide ring is provided on the side surface of the metal conductor.

[0007] As a further improvement of the present invention, an inner heat sink is provided on the inner wall of the upper cover plate.

[0008] As a further improvement of the present invention, an outer heat sink is provided on the outer wall of the upper wiring board.

[0009] As a further improvement of the present invention, a limiting plate is provided on the upper part of the inner cavity of the stationary contact seat, and a buffer component is provided on the metal conductor between the metal conductor and the stationary contact seat.

[0010] As a further improvement of the present invention, the outer surface of the metal conductor is provided with a groove capable of limiting the spring contact.

[0011] As a further improvement of the present invention, the gas insulating medium is nitrogen.

[0012] As a further improvement of the present invention, the gas insulating medium is dry compressed air.

[0013] Compared with the prior art, the present invention has the beneficial effect: in this solution, 3150A current can flow out through the static conductive rod at the upper end of the vacuum interrupter, the metal conductor, the spring contact, the static contact seat, and finally through the upper terminal board, thereby achieving a high current-carrying capacity of 3150A. At the same time, when the vacuum interrupter is closed, the closing bounce of the vacuum circuit breaker can be effectively suppressed through the buffer component. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0015] Figure 1 The present invention is a schematic structural diagram of a static contact transmission structure of a high current-carrying 126kV vacuum circuit breaker.

[0016] Figure 2 It is a schematic structural diagram of the metal conductor of the present invention.

[0017] Figure 3 It is a structural schematic diagram of the upper cover plate of the present invention.

[0018] In the figure: 1. vacuum arc extinguishing chamber; 2. metal conductor; 3. spring contact; 4. static contact seat; 5. heat conducting rod; 6. upper cover plate; 61. inner heat sink; 7. grounding bar; 8. upper terminal block; 81. outer heat sink; 9. limit plate; 10. guide ring; 11. buffer assembly; 12. gas insulating medium; 13. bushing. DETAILED DESCRIPTION

[0019] In order to make the technical solution and beneficial effects of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0020] Reference Figure 1 and Figure 2The embodiment of the present invention discloses a high current carrying 126kV vacuum circuit breaker static contact transmission structure, including a bushing 13 and a vacuum interrupter 1 arranged in the bushing 13, an upper wiring board 8 is arranged on the top of the bushing 13, an upper cover plate 6 is installed on the upper wiring board 8, a static contact seat 4 is fixedly connected to the bottom of the upper wiring board 8, and the static contact seat 4 is arranged inside the bushing 13, a metal conductor 2 is arranged on the top of the vacuum interrupter 1, the metal conductor 2 is slidably connected to the inner cavity of the static contact seat 4, a plurality of spring contacts 3 are arranged on the side of the metal conductor 2, a heat conducting rod 5 is fixedly connected to the metal conductor 2, a grounding bar 7 is arranged on the top of the heat conducting rod 5, and the grounding bar 7 is slidably connected to the inner cavity of the upper wiring board 8, and a gas insulating medium 12 is filled in the chamber between the vacuum interrupter 1, the metal conductor 2, the spring contact 3, the static contact seat 4 and the bushing 13.

[0021] The gas insulating medium 12 can be nitrogen or dry compressed air. The gas insulating medium 12 is filled between the vacuum interrupter 1, the metal conductor 2, the spring contact 3, the stationary contact seat 4 and the bushing 13, and mainly serves as the external insulation of the vacuum interrupter 1, and also serves as a convection heat dissipation.

[0022] Among them, 3150A current can flow out through the static conductive rod at the upper end of the vacuum interrupter 1, the metal conductor 2, the spring contact 3, the static contact seat 4, and finally through the upper terminal board 8; the heat of the vacuum interrupter 1 can flow out through the static conductive rod at the upper end of the vacuum interrupter 1, the metal conductor 2, the spring contact 3, the static contact seat 4, and finally through the upper terminal board 8; the heat conducting rod 5 and the grounding bar 7 can quickly transfer the heat of the metal conductor 2 to the upper cover plate 6, so as to keep the temperature rise of the vacuum interrupter 1 and the metal conductor 2 meeting the requirements.

[0023] Reference Figure 1 and Figure 3 An inner heat sink 61 is provided on the inner wall of the upper cover plate, and an outer heat sink 81 is provided on the outer wall of the upper wiring board 8. The inner heat sink 61 and the outer heat sink 81 are sheet-like structures, which can receive heat transferred from the upper cover plate 6, the grounding bar 7 and the upper wiring board 8, and transfer it to the surrounding environment by radiation and convection.

[0024] Reference Figure 2 The outer surface of the metal conductor 2 is provided with a groove capable of limiting the spring contact 3. Set in the groove, the spring contact 3 plays an effective electrical connection role between the metal conductor 2 and the stationary contact seat 4. Its inner and outer circles respectively achieve multi-point effective contact with the outer groove surface of the metal conductor and the inner circle surface of the stationary contact seat, and can achieve a current carrying capacity of 4000A.

[0025] A limit plate 9 is provided at the upper part of the inner cavity of the static contact seat 4, and a buffer component 11 is provided on the metal conductor 2 between the metal conductor 2 and the static contact seat 4. When the vacuum interrupter 1 is closed, the internal moving contact and the static contact contact and collide at high speed, causing the vacuum interrupter 1 and the metal conductor 2 to move together in the direction of the upper terminal board 8. Since a buffer component 11 is provided between the metal conductor 2 and the static contact seat 4, the metal conductor 2 enters the closing overshoot stage during its movement, avoiding rigid collision during closing and achieving a buffering effect; after being compressed, the buffer component 11 gives the metal conductor an opposite force, prompting the vacuum interrupter 1 and the metal conductor 2 to reset, preventing the displacement of the vacuum interrupter, and ensuring the contact between the moving and static contacts. The guide ring 10 axially limits the metal conductor 2 to ensure the guidance of its movement.

[0026] A guide ring 10 is provided on the side of the metal conductor 2. In the overshoot stage of closing, when the metal conductor 2 moves to the limit plate 9, the limit plate 9 stops the metal conductor 2 to prevent the vacuum interrupter 1 from increasing its stroke.

[0027] It should be understood that the specific embodiments described herein are only used to understand the present invention and are not used to limit the present invention. All other embodiments obtained by those skilled in the art without making any creative work are within the scope of protection of the present invention.

Claims

1. A high current carrying 126kV vacuum circuit breaker static contact transmission structure, characterized in that: The invention comprises a bushing (13) and a vacuum interrupter (1) arranged in the bushing (13); an upper wiring board (8) is arranged on the top of the bushing (13); an upper cover (6) is installed on the upper wiring board (8); a static contact seat (4) is fixedly connected to the bottom of the upper wiring board (8); the static contact seat (4) is arranged inside the bushing (13); a metal conductor (2) is arranged on the top of the vacuum interrupter (1); the metal conductor (2) is slidably connected to the inner cavity of the static contact seat (4); and a side of the metal conductor (2) is provided. A plurality of spring contacts (3) are provided, a heat conducting rod (5) is fixedly connected to the metal conductor (2), a grounding bar (7) is provided on the top of the heat conducting rod (5), the grounding bar (7) is slidably connected to the inner cavity of an upper wiring board (8), a gas insulating medium (12) is filled in the cavity between the vacuum interrupter (1), the metal conductor (2), the spring contact (3), the stationary contact seat (4) and the bushing (13), and a buffer component (11) is provided on the metal conductor (2) between the metal conductor (2) and the stationary contact seat (4).

2. A high current carrying 126kV vacuum circuit breaker static contact transmission structure according to claim 1, characterized in that: A guide ring (10) is provided on the side of the metal conductor (2).

3. A high current carrying 126kV vacuum circuit breaker static contact transmission structure according to claim 2, characterized in that: An inner heat sink (61) is provided on the inner wall of the upper cover plate.

4. A high current carrying 126kV vacuum circuit breaker static contact transmission structure according to claim 3, characterized in that: An outer heat sink (81) is provided on the outer wall of the upper wiring board (8).

5. A high current carrying 126kV vacuum circuit breaker static contact transmission structure according to claim 4, characterized in that: A limiting plate (9) is provided at the upper portion of the inner cavity of the stationary contact seat (4).

6. A high current carrying 126kV vacuum circuit breaker static contact transmission structure according to claim 5, characterized in that: The outer surface of the metal conductor (2) is provided with a groove capable of limiting the spring contact (3).

7. A high current carrying 126kV vacuum circuit breaker static contact transmission structure according to claim 1, characterized in that: The gas insulating medium (12) is nitrogen.

8. The high current carrying 126kV vacuum circuit breaker static contact transmission structure according to claim 1 is characterized in that: The gas insulating medium (12) is dry compressed air.

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