Gas-insulated switchgear and gas-insulated switchgear

Abstract

To ensure the insulation performance of a gas-insulated switchgear, and allow the device to be laid out horizontally in a duct-type configuration, thereby reducing the overall size of the device.SOLUTION: A gas-insulated switchgear 1 includes a gas-insulated switchgear unit 2 having a breaker pressure chamber 3a, a drive pressure chamber 4, and a link mechanism pressure chamber 5. The breaker pressure chamber 3a insulates and houses three-phase breakers 6 that are arranged upright in a triangular configuration. The drive pressure chamber 4 includes a metal bellows 69 that expands and contracts freely within the breaker pressure chamber 3a in response to the opening and closing operation of the breaker 6. The internal pressure of the drive pressure chamber 4 is set lower than the internal pressure of the breaker pressure chamber 3a. The single link mechanism pressure chamber 5 that communicates with the drive pressure chamber 4 is located directly below the drive pressure chamber 4. The single link mechanism pressure chamber 5 houses a link mechanism 8 that operates in conjunction with an operating device 7 to open and close the breaker 6 using the operating device 7.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a structure of a circuit breaking section in a duct-type gas insulated switchgear. [Background technology]

[0002] An example of the structure of a gas-insulated switchgear having a vacuum circuit breaker is the gas-insulated switchgear disclosed in Patent Document 1. According to this device, by setting the pressure in the interrupter vessel of the vacuum circuit breaker lower than that of other busbar units, it is possible to ensure the insulation performance of the device using gas with low insulation properties such as dry gas without using greenhouse gases such as SF6 gas.

[0003] Furthermore, an example of a vacuum circuit breaker that employs a structure that increases the gas pressure in the container that houses the circuit breaker is the gas-insulated switchgear described in Patent Document 2. This device allows the gas pressure in the container that houses the circuit breaker to be increased, thereby reducing the required insulation distance and enabling the vacuum circuit breaker to be made smaller overall. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5452780 [Patent Document 2] Japanese Patent Application Laid-Open No. 4749495 Summary of the Invention [Problem to be solved by the invention]

[0005] In the gas-insulated switchgear of Patent Document 1, the pressure in the interrupter vessel of the vacuum circuit breaker must be lower than that of the other busbar units, resulting in a relatively low dielectric strength compared to the busbar units. Furthermore, if a gas with poor insulation performance, such as dry air, is filled in instead of SF6 gas, which has excellent insulation properties, the required insulation distance increases, making the device larger. As a result, it is not possible to reduce the size of the interrupter, and therefore it is not possible to reduce the size of the entire device, including the vacuum circuit breaker.

[0006] Furthermore, in the gas-insulated switchgear of Patent Document 2, the connection portion of the horizontally arranged circuit breaker is structured to accommodate air bushing connections, so it is not possible to configure a layout for a conduit-type gas-insulated switchgear having other unit connections in the horizontal direction.

[0007] In view of the above circumstances, an object of the present invention is to ensure the insulation performance of a gas-insulated switchgear and to make it possible to accommodate a horizontal duct-type device layout, thereby reducing the size of the entire device. [Means for solving the problem]

[0008] Therefore, one aspect of the present invention is a gas insulated switching unit having a circuit breaker pressure chamber that insulates and houses three-phase circuit breakers that are arranged upright in a triangular configuration, a drive unit pressure chamber that includes the inside of a metal bellows that is expandable and contractible within the circuit breaker pressure chamber in response to the opening and closing operation of the circuit breakers, and a single link mechanism pressure chamber that communicates with the drive unit pressure chamber and is located directly below the drive unit pressure chamber, wherein the internal pressure of the drive unit pressure chamber is set lower than the internal pressure of the circuit breaker pressure chamber, and the single link mechanism pressure chamber houses a link mechanism that operates in conjunction with an operating device for the circuit breakers to open and close the circuit breakers.

[0009] In one aspect of the present invention, in the gas insulated switching unit, the link mechanism includes a rotary seal shaft that can rotate back and forth in conjunction with the rotary shaft of the operating device, a shaft connecting member that can move back and forth horizontally in conjunction with the rotary seal shaft, a main shaft that can rotate back and forth in conjunction with the shaft connecting member, and a rod connecting member that is connected to an insulating rod that opens and closes the circuit breaker, and can move back and forth vertically in conjunction with the main shaft.

[0010] In one aspect of the present invention, in the gas insulated switching unit, the interrupter comprises: a vacuum interrupter; a main circuit conductor that is erected by an insulating support cylinder within the interrupter pressure chamber and through which the insulating rod is inserted to connect to the vacuum interrupter; a sealing member that airtightly seals one end of the main circuit conductor, one end of the vacuum interrupter, and one end of the metal bellows; an energizing contact that supports a movable lead of the vacuum interrupter coaxially with the main circuit conductor within the main circuit conductor; and a biasing member that is attached to the movable lead so that the insulating rod biases the movable lead in the axial direction of the insulating rod within the main circuit conductor.

[0011] In one aspect of the present invention, in the gas insulated switchgear unit, the outer peripheral surface of the main circuit conductor is It is coated with insulating resin.

[0012] One aspect of the present invention is a gas-insulated switchgear including any one of the gas-insulated switchgear units described above. [Effects of the Invention]

[0013] According to the present invention, the insulation performance of the gas-insulated switchgear can be ensured, and the device can be adapted to a horizontal duct-type device layout, thereby making it possible to reduce the size of the entire device. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a longitudinal sectional view of a gas-insulated switchgear according to an embodiment of the present invention; [Figure 2] Cross section AA of Figure 1. [Figure 3] 1 is a longitudinal sectional view of a circuit breaker of a gas-insulated switchgear unit according to an embodiment of the present invention; [Figure 4] FIG. 2 is a plan view of a link mechanism of the gas-insulated switchgear unit. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0016] The gas-insulated switchgear 1 shown in Figure 1, which is one embodiment of the present invention, comprises a gas-insulated switch unit 2, and busbar disconnector units 11 and 12 and a line disconnector unit 13 connected to the gas-insulated switch unit 2.

[0017] The gas insulated switchgear unit 2 has a breaker pressure chamber 3a, a drive pressure chamber 4, and a link mechanism pressure chamber 5 as described below.

[0018] The circuit breaker pressure chamber 3a is made of a cylindrical metal tank 3 that insulates and houses three-phase circuit breakers 6 that are arranged in a triangular cross section as shown in Figure 2. The circuit breaker pressure chamber 3a is filled with an insulating gas other than SF6 gas, such as dry air.

[0019] The internal pressure of the circuit breaker pressure chamber 3a is set higher than the internal pressure of the drive unit pressure chamber 4 (for example, 0.5 MPa·G). Conductors 14 and 15 that connect the busbar disconnector units 11 and 12 to the circuit breaker unit 6, and a conductor 16 that connects the line disconnector unit 13 to the circuit breaker unit 6 are introduced into this circuit breaker pressure chamber 3a.

[0020] 3, the interrupter unit 6 has a two-pressure structure and includes a vacuum interrupter 61, a main circuit conductor 62, a sealing member 63, a current-carrying contact 64, and a biasing member 65. The main circuit conductor 62 is supported by an insulating support cylinder 66 at the bottom 31 of the interrupter pressure chamber 3a. The outer peripheral surface of the main circuit conductor 62 is coated with an insulating resin such as epoxy resin.

[0021] An insulating rod 67 that operates a movable lead 68 of the vacuum interrupter 61 is inserted into the main circuit conductor 62. The insulating rod 67 is connected to the movable lead 68 via a biasing member 65. A sealing member 63 airtightly seals one end of the main circuit conductor 62, one end of the vacuum interrupter 61, and one end of a metal bellows 69. The metal bellows 69 is expandable and contractible in response to the opening and closing operation of the vacuum interrupter 61 (operation of the movable lead 68). A current-carrying contact 64 supports the movable lead 68 within the main circuit conductor 62 so that it can move in the axial direction of the main circuit conductor 62. The biasing member 65 is made of a pressure spring and is attached to the movable lead 68, and the insulating rod 67 biases the movable lead 68 in the axial direction of the insulating rod 67 within the main circuit conductor 62.

[0022] As shown in the figure, the drive unit pressure chamber 4 includes the inside of a metal bellows 69 that is coaxial with the vacuum interrupter 61 of the interrupter 6 within the interrupter pressure chamber 3a. The drive unit pressure chamber 4 is filled with dry air, just like the interrupter pressure chamber 3a. The internal pressure of the drive unit pressure chamber 4 is set lower than the internal pressure of the interrupter pressure chamber 3a (for example, 0.16 MPa·G).

[0023] 1 and 2, the link mechanism pressure chamber 5 is connected to the drive unit pressure chamber 4 via a through-hole 30 in the bottom 31 of the cutoff unit pressure chamber 3a, through which the insulating rod 67 is inserted, and is disposed directly below the drive unit pressure chamber 4. A link mechanism 8 is housed within the link mechanism pressure chamber 5, which is connected to the operating device 7 of the vacuum interrupter 61 and causes the operating device 7 to open and close the vacuum interrupter 61 of the cutoff unit 6. The link mechanism pressure chamber 5 is housed within a support container 9 that supports the cutoff unit pressure chamber 3a in an upright position. Since the link mechanism pressure chamber 5 is connected to the drive unit pressure chamber 4 as described above, dry air is filled in the link mechanism pressure chamber 5 to the same pressure as the drive unit pressure chamber 4.

[0024] The link mechanism 8 has a rotary seal shaft 81, a shaft connecting member 82, a main shaft 83, and a rod connecting member 84. The operating device 7 has a rotary shaft 71, a rotary lever 72, a breaking spring 73, a tripping mechanism 74, a tripping electromagnet 75, etc., and the rotary shaft 71 is connected to the rotary lever 72.

[0025] The rotary seal shaft 81 can reciprocate in conjunction with the rotary shaft 71 of the operating device 7, which is operated on the air side. The shaft connecting member 82 can reciprocate horizontally in conjunction with the rotary seal shaft 81. The main shaft 83 can reciprocate in conjunction with the shaft connecting member 82. Two main shafts 83 are provided in parallel to correspond to the three-phase interrupter units 6 arranged as shown in FIG. 2. Near the center of one main shaft 83, a connecting member 85 (see FIGS. 1 and 4) is connected to one interrupter unit 6 arranged near the center of the interrupter unit pressure chamber 3a (see FIG. 2). Near both ends of the other main shaft 83, two interrupter units 6 arranged near the inner surface of the interrupter unit pressure chamber 3a (see FIG. 2) are connected via connecting members 85 (see FIGS. 1 and 4). The rod connecting member 84 is connected to the insulating rod 67 connected to the movable lead 68 of the vacuum interrupter 61 (see FIG. 3) and can reciprocate vertically in conjunction with the main shaft 83.

[0026] An example of the operation of the interrupter unit 6 will be described with reference to FIGS.

[0027] When the rotary shaft 71 rotates in one direction (for example, counterclockwise) due to the closing operation of the operating device 7, the rotary seal shaft 81 rotates in that direction in conjunction with the rotary shaft 71, and the power is transmitted to the two main shafts 83. These two main shafts 83 rotate in that direction in conjunction with the rotary seal shaft 81 due to the power. The three-phase insulating rod 67 is pushed upward in conjunction with the two main shafts 83, and as a result, the movable contact of the vacuum interrupter 61 (movable reed 68) is pushed upward. At the same time that the movable contact of the vacuum interrupter 61 comes into contact with the fixed contact, the biasing member 65 applies an upward force. When the rotary shaft 71 rotates to the operation completion position, the closing operation of the circuit breaker 6 is completed.

[0028] When the rotary shaft 71 rotates in the other direction (for example, clockwise) due to the opening operation of the operating device 7, the rotary seal shaft 81 rotates in the other direction in conjunction with the rotary shaft 71, and the power is transmitted to the two main shafts 83. These two main shafts 83 rotate in the other direction in conjunction with the rotary seal shaft 81 due to the power. The three-phase insulating rod 67 is pulled downward in conjunction with the two main shafts 83, and accordingly, the movable contact of the vacuum interrupter 61 (movable reed 68) is pulled downward. Then, when the rotary shaft 71 rotates to the operation completion position, the contact of the vacuum interrupter 61 maintains the required distance, and the opening operation of the circuit breaker 6 is completed.

[0029] According to the above-described circuit breaker 6, the configuration of the circuit breaker pressure chamber 3a, the drive unit pressure chamber 4, and the link mechanism pressure chamber 5 ensures the insulation performance of the gas insulated switching unit 2 and makes it possible to accommodate a horizontal, conduit-type device layout, thereby reducing the size of the entire device.

[0030] In particular, in the link mechanism 8, the rotary seal shaft 81 can rotate back and forth in conjunction with the rotary shaft 71 of the operating device 7, the shaft connecting member 82 can move back and forth horizontally in conjunction with the rotary seal shaft 81, and further, the main shaft 83 can rotate back and forth in conjunction with the shaft connecting member 82, and the rod connecting member 84 can move back and forth vertically in conjunction with the main shaft 83, so that the link mechanism pressure chamber 5 that stores the link mechanism 8 can be located directly below the drive unit pressure chamber 4. This makes it possible to ensure the insulation performance of the gas-insulated switchgear 1 using gases with low insulation properties such as dry gases without requiring greenhouse gases such as SF6 gas, and also makes it possible to make the entire device more compact.

[0031] In the circuit breaking unit 6, the sealing member 63 airtightly seals one end of the main circuit conductor 62, one end of the vacuum interrupter 61, and one end of the metal bellows 69, the current-carrying contact 64 supports the movable reed 68 coaxially with the main circuit conductor 62 within the main circuit conductor 62, and the biasing member 65 is attached to the movable reed 68 within the main circuit conductor 62 so that the insulating rod 67 biases the movable reed 68 in the axial direction of the insulating rod 67, thereby ensuring insulation of the movable reed 68 operating within the main circuit conductor 62. Furthermore, the metal bellows 69 expands and contracts in response to the opening and closing operation of the vacuum interrupter 61, thereby constantly reducing the pressure difference between the vacuum inside the vacuum interrupter 61 and the outside of the vacuum interrupter 61 and reducing the energy required for the circuit breaking operation. Furthermore, the reduced stress on the metal bellows 69 extends the life of the metal bellows 69 and improves reliability during repeated opening and closing.

[0032] Furthermore, by coating the surface of the main circuit conductor 62 with insulating resin, the tiny protrusions on the surface of the main circuit conductor 62 are smoothed and the apparent shape of the surface is improved, thereby improving the voltage resistance performance of the main circuit conductor 62. [Explanation of symbols]

[0033] 1...Gas-insulated switchgear, 2...Gas insulated switchgear unit 3...metal tank, 3a...insulating section pressure chamber, 30...through hole, 31...bottom 4...Driver pressure chamber 5...Link mechanism pressure chamber 6...breaker, 61...vacuum interrupter, 62...main circuit conductor, 63...sealing member, 64...current-carrying contact, 65...biasing member, 66...insulating support tube, 67...insulating rod, 68...movable lead, 69...metal bellows 7...Operating device, 71...Rotating shaft, 72...Rotating lever, 73...Breaking spring, 74...Trip mechanism, 75...Trip electromagnet 8... Link mechanism, 81 Rotating seal shaft, 82... Shaft connecting member, 83... Main shaft, 84... Rod connecting member, 85... Connecting member 11, 12... Busbar disconnector unit 13...Line disconnector unit 14, 15, 16...conductor

Claims

1. a breaker pressure chamber that insulates and houses three-phase breakers that are erected in a triangular arrangement; a drive section pressure chamber including an interior of a metal bellows that is expandable and contractible in response to the opening and closing operation of the cutoff section within the cutoff section pressure chamber; a single link mechanism pressure chamber that is in communication with the drive unit pressure chamber and is disposed directly below the drive unit pressure chamber; and the internal pressure of the drive section pressure chamber is set lower than the internal pressure of the cutoff section pressure chamber, a gas insulated switchgear unit, wherein the single link mechanism pressure chamber houses a link mechanism that performs opening and closing operations of the circuit breaker in cooperation with an operating device of the circuit breaker.

2. The link mechanism includes: a rotary seal shaft that can rotate back and forth in conjunction with the rotary shaft of the operating device; a shaft connecting member that can reciprocate horizontally in conjunction with the rotary seal shaft; a main shaft that can rotate back and forth in conjunction with the shaft connecting member; a rod connecting member connected to an insulating rod that opens and closes the interrupter, and that is movable back and forth in a vertical direction in conjunction with the main shaft; 2. The gas insulated switchgear unit according to claim 1, further comprising:

3. A gas-insulated switchgear comprising the gas-insulated switchgear unit according to claim 1 or 2.

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