Breaker device

Abstract

Provided is a breaker device having sufficient withstand voltage performance even when a vacuum circuit breaker is used. In a breaker device of one embodiment, a first breaking contact is connected in parallel with an energization contact, and a second breaking contact is connected in parallel with the energization contact and also connected in series to the first breaking contact. The first breaking contact is configured by a vacuum circuit breaker, and the second breaking contact and the energization contact are configured by a gas circuit breaker. When executing an electric path activation operation for putting an electric path into an energized state from a breaking state, a breaking contact activation operation, a second breaking contact activation operation, and an energization contact activation operation are executed. The completion time point of the first breaking contact activation operation is before the completion time point of the second breaking contact activation operation, and the completion time point of the second breaking contact activation operation is before the completion time point of the energization contact activation operation.

Description

Circuit breaker

[0001] SUMMARY OF THE INVENTION An embodiment of the present invention relates to a shutoff device.

[0002] 2. Description of the Related Art When an accident occurs in a power system, a circuit breaker such as a vacuum circuit breaker or a gas circuit breaker is used to switch an electric circuit through which current flows from a conducting state to a cut-off state.

[0003] A vacuum circuit breaker is configured to perform opening and closing operations of a pair of contacts (electrodes) inside a vacuum vessel that is in a vacuum state. Specifically, when the vacuum circuit breaker is to energize an electric circuit, the pair of contacts approach each other in a vacuum atmosphere, becoming a closed state and electrically connected. When the vacuum circuit breaker is to interrupt the electric circuit, the pair of contacts move apart in a vacuum atmosphere, becoming an open state and electrically insulated.

[0004] The gas circuit breaker is configured to perform a switching operation with a pair of contacts inside a grounded container filled with insulating gas. Specifically, when the gas circuit breaker is placed in a conducting state, the pair of contacts approach each other in an atmosphere filled with insulating gas, thereby achieving a closed state and an electrically connected state. When the gas circuit breaker is placed in a disconnected state, the pair of contacts move apart in an atmosphere filled with insulating gas, thereby achieving an open state and an electrically isolated state. When the gas circuit breaker performs a disconnecting operation to switch from a closed state to an open state, for example, insulating gas is sprayed onto the arc discharge that occurs during the disconnecting operation in order to extinguish the arc discharge.

[0005] In gas circuit breakers, the insulating gas is mainly SF6 in order to obtain sufficient insulation performance, arc extinguishing performance, etc. ６ Gas circuit breakers use sulfur hexafluoride gas. Gas circuit breakers have excellent insulation and arc extinguishing properties, making them suitable for use in circuits that are subject to higher voltages than those that vacuum circuit breakers interrupt (electrical circuits of the power transmission class, etc.).

[0006] Patent No. 6057887

[0007] SF is the main insulating gas used in gas circuit breakers. ６Gas has a high greenhouse effect potential. ６ Although techniques using insulating gases other than SF6 have been proposed, it is not easy to obtain sufficient performance. ６ When a naturally occurring gas such as dry air is used as the insulating gas in a gas circuit breaker instead of conventional gas, the arc-extinguishing ability of the gas circuit breaker to extinguish the arc discharge is low, which may result in a decrease in the interrupting performance.

[0008] For this reason, it has been considered to configure a circuit breaker by combining a gas circuit breaker and a vacuum circuit breaker. However, in a circuit breaker configured by combining a gas circuit breaker and a vacuum circuit breaker, the following problems may occur.

[0009] Specifically, when a pair of contacts constituting a vacuum interrupter is brought closer to each other to perform a closing operation that changes the vacuum interrupter from an open state to a closed state, if a pre-arc discharge occurs between the pair of contacts, the metallic material constituting the pair of contacts may melt due to the pre-arc discharge. As a result, in the vacuum interrupter, the pair of contacts may become partially welded. Therefore, when a subsequent interruption operation that changes the vacuum interrupter from a closed state to an open state is performed, the welded portion of the pair of contacts constituting the vacuum interrupter is peeled off, causing the surfaces of the pair of contacts to become rough. When the surfaces of the contacts in the vacuum interrupter become rough, the electron multiplication factor increases, making electron avalanches more likely to occur, which may reduce the withstand voltage performance of the vacuum interrupter.

[0010] Due to the above circumstances, in a circuit breaker constructed by combining a gas circuit breaker and a vacuum circuit breaker, it is not easy to improve the voltage resistance performance of the entire circuit breaker due to the reduced voltage resistance performance of the vacuum circuit breaker.

[0011] Therefore, the problem to be solved by the present invention is to provide a circuit breaker that has sufficient voltage resistance performance even when a vacuum circuit breaker is used.

[0012] The circuit breaker of the embodiment has an energizing contact, a first breaking contact, and a second breaking contact. The first breaking contact is connected in parallel with the energizing contact. The second breaking contact is connected in parallel with the energizing contact and in series with the first breaking contact. The first breaking contact is configured as a vacuum circuit breaker that switches between a closed state and an open state inside a vacuum container. The second breaking contact and the energizing contact are configured as gas circuit breakers that switch between a closed state and an open state inside an insulating gas container filled with insulating gas. When performing an electric circuit closing operation to change an electric circuit from an interrupted state to an energized state, the circuit breaker of the embodiment performs a first breaking contact closing operation to change the first breaking contact from an open state to a closed state, a second breaking contact closing operation to change the second breaking contact from an open state to a closed state, and an energizing contact closing operation to change the energizing contact from an open state to a closed state. The completion time of the first breaking contact closing operation is before the completion time of the second breaking contact closing operation, and the completion time of the second breaking contact closing operation is before the completion time of the energizing contact closing operation. When the first breaking contact closing operation and the second breaking contact closing operation are completed, a current flows through the first breaking contact and the second breaking contact, and when the energizing contact closing operation is completed, a larger current flows through the energizing contact than through the first breaking contact and the second breaking contact.

[0013] FIG. 1 is a circuit diagram of a circuit breaker 100 according to the first embodiment. FIG. 2A is a cross-sectional view schematically illustrating the configuration of the circuit breaker 100 according to the first embodiment. FIG. 2B is a cross-sectional view illustrating a detailed configuration of a gas circuit breaker 251 in the circuit breaker 100 according to the first embodiment. FIG. 3A is a circuit diagram illustrating the operation of the circuit breaker 100 according to the first embodiment. FIG. 3B is a circuit diagram illustrating the operation of the circuit breaker 100 according to the first embodiment. FIG. 3C is a circuit diagram illustrating the operation of the circuit breaker 100 according to the first embodiment. FIG. 4A is a cross-sectional view illustrating a state when a second breaking contact closing operation (ST2) is performed in the gas circuit breaker 251 constituting the circuit breaker 100 according to the first embodiment. FIG. 4B is a cross-sectional view illustrating a state when a conducting contact closing operation (ST3) is performed in the gas circuit breaker 251 constituting the circuit breaker 100 according to the first embodiment. FIG. 5 is a view illustrating the electrical circuit closing operations (first breaking contact closing operation (ST1), second breaking contact closing operation (ST2), and conducting contact closing operation (ST3)) performed in the first embodiment. FIG. 6 is a diagram showing the electrical circuit closing operation (first breaking contact closing operation (ST1), second breaking contact closing operation (ST2), and energizing contact closing operation (ST3)) performed in Modification 1-1 of the first embodiment. FIG. 7 is a diagram showing the electrical circuit closing operation (first breaking contact closing operation (ST1), second breaking contact closing operation (ST2), and energizing contact closing operation (ST3)) performed in the second embodiment. FIG. 8A is a cross-sectional view schematically showing the configuration of a circuit breaker 100 according to a third embodiment. FIG. 8B is a diagram showing the electrical circuit closing operation (first breaking contact closing operation (ST1), second breaking contact closing operation (ST2), and energizing contact closing operation (ST3)) performed in the third embodiment. FIG. 9 is a cross-sectional view schematically showing the configuration of a vacuum circuit breaker 211 including a first breaking contact 111 in a circuit breaker according to a fourth embodiment.

[0014] First Embodiment [A] Circuit of Breaker Device 100 FIG. 1 is a circuit diagram of a breaker device 100 according to a first embodiment.

[0015] 1, the circuit breaker 100 of this embodiment is a device having an energizing contact 101, a first breaking contact 111, and a second breaking contact 112, and is installed on an electric circuit EC, and is configured to switch the electric circuit EC from an energized state to a broken state. Here, the circuit breaker 100 includes an energizing electric circuit EC1 and a breaking electric circuit EC2 as the electric circuits EC, and the breaking electric circuit EC2 is connected in parallel to the energizing electric circuit EC1 so as to bypass the energizing contact 101.

[0016] The following describes each component of the circuit breaker 100. Note that Fig. 1 shows a state in which the circuit breaker 100 has switched the electrical circuit EC to an interrupted state.

[0017] [A-1] Current-carrying contact 101 The current-carrying contact 101 is installed in the current-carrying electric circuit EC1. The current-carrying contact 101 is configured to have a lower resistance than the first breaking contact 111 and the second breaking contact 112. For example, the current-carrying contact 101 has a larger current-carrying cross-sectional area than the first breaking contact 111 and the second breaking contact 112, and is configured using a conductive material with a higher conductivity than the first breaking contact 111 and the second breaking contact 112.

[0018] [A-2] First Breaker Contact 111 The first breaker contact 111 is installed in the breaking electric circuit EC2 so as to be connected in parallel with the conducting contact 101.

[0019] [A-3] Second Breaker Contact 112 The second breaker contact 112 is connected in parallel with the energizing contact 101 and is also installed in the breaking electrical circuit EC2 so as to be connected in series with the first breaker contact 111.

[0020] [B] Detailed Configuration of the Circuit Breaker 100 Fig. 2A is a cross-sectional view schematically illustrating the configuration of the circuit breaker 100 according to the first embodiment. Fig. 2A illustrates the circuit breaker 100 in a circuit breaker state.

[0021] 2A, the circuit breaker 100 of this embodiment accommodates a vacuum circuit breaker 211 and a gas circuit breaker 251 inside a grounded tank 200. Each part constituting the circuit breaker 100 will be described in order.

[0022] [B-1] Grounded Tank 200 The grounded tank 200 is made of a metal material and is electrically connected to a reference potential point (such as the earth). The inside of the grounded tank 200 is filled with insulating gas.

[0023] Here, the insulating gas is, for example, SF ６ It has a lower greenhouse effect potential than SF gas, but ６ It may also be a gas. ６ The insulating gas having a greenhouse effect coefficient smaller than that of the gas is, for example, carbon dioxide, oxygen, nitrogen, or the like, and may be a mixed gas of the above-mentioned gases.

[0024] [B-2] Vacuum circuit breaker 211 (first interrupting contact 111) The vacuum circuit breaker 211 is a vacuum valve, and accommodates a movable electrode 111A and a fixed electrode 111B as the first interrupting contact 111 inside a vacuum container 212. The vacuum circuit breaker 211 is configured so that the first interrupting contact 111 switches between a closed state and an open state inside the vacuum container 212.

[0025] Here, the vacuum vessel 212 includes a porcelain tube 212a and a pair of flanges 212b, and for example, the pair of flanges 212b are provided at both ends of the cylindrical porcelain tube 212a. The porcelain tube 212a is made of an insulating material (ceramic, etc.), and the pair of flanges 212b are made of, for example, a metal material. The interior of the vacuum vessel 212 is in a vacuum state, and the pressure inside the vacuum vessel 212 is lower than the pressure inside the grounded tank 200.

[0026] The movable electrode 111A and the fixed electrode 111B are, for example, disk-shaped and made of a metal material, and are installed inside the vacuum vessel 212 so that their ends face each other. In this example, the movable electrode 111A is installed at the end of the vacuum circuit breaker movable current-carrying shaft 214. The fixed electrode 111B is installed at the end of the vacuum circuit breaker fixed current-carrying shaft 213. The vacuum circuit breaker fixed current-carrying shaft 213 is installed so as to be aligned coaxially with the vacuum circuit breaker movable current-carrying shaft 214. The vacuum circuit breaker fixed current-carrying shaft 213 is supported by a support part SP made of an insulating material.

[0027] Furthermore, the vacuum circuit breaker movable current-carrying shaft 214 is connected to an operating mechanism 217 via an insulating rod 216. The operating mechanism 217 is configured to operate the vacuum circuit breaker movable current-carrying shaft 214, for example, by using an electric spring or an electromagnetic repulsion mechanism. The vacuum circuit breaker 211 is placed in a closed state by the operation of the operating mechanism 217, when the movable electrode 111A and the fixed electrode 111B are brought into contact with each other, and is placed in an open state by the operation of the operating mechanism 217, when the movable electrode 111A and the fixed electrode 111B are brought into a separated state.

[0028] The vacuum circuit breaker movable current-carrying shaft 214 is slidably supported by a sliding portion SL214. The sliding portion SL214 is made of a metal material and is electrically connected to the electric wire EC1a via the electric wire EC2a. The electric wire EC2a constitutes the interrupting electric circuit EC2 (see FIG. 1).

[0029] The vacuum vessel 212 further contains a bellows 215 and an arc shield 218 .

[0030] The bellows 215 is cylindrical, and the vacuum circuit breaker movable current-carrying shaft 214 passes through it. The internal space of the bellows 215 communicates with the internal space of the grounded tank 200. The bellows 215 is configured to expand and contract in the direction of movement when the movable electrode 111A moves in accordance with the sliding of the vacuum circuit breaker movable current-carrying shaft 214.

[0031] The arc shield 218 is disposed so as to surround the movable electrode 111A and the fixed electrode 111B in the circumferential direction.

[0032] [B-3] Gas circuit breaker 251 (current-carrying contact 101, second breaker contact 112) As shown in Fig. 2A, the gas circuit breaker 251 includes a gas circuit breaker movable current-carrying shaft 401 and a gas circuit breaker fixed current-carrying shaft 253. The gas circuit breaker movable current-carrying shaft 401 is provided with a driving-side arcing contact 451 and a driving-side current-carrying contact 455. The gas circuit breaker fixed current-carrying shaft 253 is aligned coaxially with the gas circuit breaker movable current-carrying shaft 401, and is provided with an opposing-side arcing contact 331 and an opposing-side current-carrying contact 335. The gas circuit breaker fixed current-carrying shaft 253 is configured integrally with the vacuum circuit breaker fixed current-carrying shaft 213, and is supported by a support part SP.

[0033] In the gas circuit breaker 251, the driving side conductive contact 455 and the opposing side conductive contact 335 function as the conductive contacts 101. In the gas circuit breaker 251, the driving side arcing contact 451 and the opposing side arcing contact 331 function as the second breaking contact 112.

[0034] 2B is a cross-sectional view showing a detailed configuration of the gas circuit breaker 251 in the circuit breaker device 100 according to the first embodiment. Hereinafter, the detailed configuration of the gas circuit breaker 251 will be described using FIG. 2B in addition to FIG. 2A.

[0035] The gas circuit breaker 251 is a puffer type, and includes an opposing side unit 3 and a driving side unit 4 as shown in FIG. 2B.

[0036] [B-3-1] Opposing Unit 3 In the gas circuit breaker 251, the opposing unit 3 includes a cooling cylinder 301, a support portion 302, and an opposing contact portion 303. The cooling cylinder 301, the support portion 302, and the opposing contact portion 303 are each formed of, for example, a metal material, and are each electrically connected to the electric wire EC1a (see FIG. 2A).

[0037] [B-3-1-1] Cooling Cylinder 301 The cooling cylinder 301 is, for example, a cylindrical tubular body and is connected to the electric wire EC1a. The cooling cylinder 301 is supported on the grounded tank 200 by a support part SP (see FIG. 2A).

[0038] [B-3-1-2] Support Portion 302 The support portion 302 includes a support ring portion 321 and a support protrusion portion 322 .

[0039] The support ring portion 321 is, for example, a circular ring-shaped body, and is installed coaxially with the cooling cylinder 301 on the end face of the cooling cylinder 301 that is located on the drive side DS. Here, the outer diameter of the support ring portion 321 is, for example, the same as the outer diameter of the cooling cylinder 301, and the inner diameter of the support ring portion 321 is, for example, the same as the inner diameter of the cooling cylinder 301.

[0040] The support protrusion 322 is, for example, a rod-shaped body, and is provided on the inner peripheral surface of the support ring portion 321 so as to protrude radially inward. In the support portion 302, the support ring portion 321 is formed using a conductive material such as metal. In contrast, the support protrusion 322 is formed using an insulating material so that the opposing arc contact 331 and the opposing current-carrying contact 335 are electrically insulated by the support protrusion 322. However, a portion of the support protrusion 322 is formed using a conductive material so as to electrically connect the gas circuit breaker fixed current-carrying shaft 253 and the opposing arc contact 331 (see FIG. 1 ).

[0041] [B-3-1-3] Opposing Contactor Section 303 The opposing contactor section 303 includes an opposing arcing contactor 331 and an opposing current-carrying contactor 335 , and is provided inside the grounded tank 200 .

[0042] [B-3-1-3-1] Opposing Arc Contactor 331 The opposing arc contactor 331 is, for example, a cylindrical rod-shaped body extending in the axial direction. The opposing arc contactor 331 is installed coaxially with the cooling cylinder 301 and the like on the surface of the support protrusion 322 located on the driving side DS. An end 331a of the opposing arc contactor 331 located on the driving side DS has a curved surface.

[0043] [B-3-1-3-2] Opposing side current-carrying contact 335 The opposing side current-carrying contact 335 is, for example, a cylindrical tubular body, and is installed coaxially with the opposing side arc contact 331, etc., via a support part 302 on the end face of the cooling cylinder 301 located on the driving side DS. The opposing side current-carrying contact 335 includes a portion that houses the opposing side arc contact 331 inside.

[0044] Here, the outer diameter of the opposing-side conductive contact 335 is, for example, the same as the outer diameter of the cooling cylinder 301, and the inner diameter of the opposing-side conductive contact 335 includes, for example, a portion that is the same as the inner diameter of the cooling cylinder 301. In the opposing-side conductive contact 335, an end 335a located on the driving side DS protrudes radially inward.

[0045] [B-3-2] Driving Side Unit 4 The driving side unit 4 includes a gas circuit breaker movable conducting shaft 401 (movable conducting shaft), a puffer cylinder 402, a puffer piston 403, a driving side contact portion 405, a cylinder support 406, a piston support 407, and an insulating nozzle 500. The gas circuit breaker movable conducting shaft 401, the puffer cylinder 402, the puffer piston 403, the driving side contact portion 405, the cylinder support 406, and the piston support 407 are each formed of, for example, a metal material, and are each electrically connected to the electric wire EC1b.

[0046] [B-3-2-1] Gas circuit breaker movable current-carrying shaft 401 The gas circuit breaker movable current-carrying shaft 401 is a rod-shaped body, and is installed coaxially with the opposing arc contact 331, etc. The gas circuit breaker movable current-carrying shaft 401 is connected to an operating mechanism 257 via an insulating rod 256. The operating mechanism 257 is configured to operate the gas circuit breaker movable current-carrying shaft 401 using, for example, an electric spring or an electromagnetic repulsion mechanism, and the gas circuit breaker movable current-carrying shaft 401 is moved in the axial direction by the operating mechanism 257.

[0047] Here, the gas circuit breaker movable current-carrying shaft 401 has a movable current-carrying shaft solid portion 411 and a movable current-carrying shaft hollow portion 412 .

[0048] The movable current-carrying shaft solid portion 411 is, for example, cylindrical.

[0049] The movable current-carrying shaft hollow portion 412 is, for example, cylindrical, and its end portion located on the driving side DS is connected to the movable current-carrying shaft solid portion 411. The outer diameter of the movable current-carrying shaft hollow portion 412 is, for example, the same as the outer diameter of the movable current-carrying shaft solid portion 411. The inner diameter of the movable current-carrying shaft hollow portion 412 is larger than the outer diameter of the opposing-side arc contact 331. A first ventilation hole H412 is formed radially through the end portion of the movable current-carrying shaft hollow portion 412 located on the driving side DS.

[0050] [B-3-2-2] Puffer Cylinder 402 The puffer cylinder 402 is configured to slide in the axial direction together with the gas circuit breaker movable current-carrying shaft 401 by the operation mechanism 257 .

[0051] Here, the puffer cylinder 402 includes a cylinder cylindrical portion 421 and a cylinder bottom plate portion 422 .

[0052] The cylinder cylindrical portion 421 is, for example, a cylindrical tubular body, and is installed coaxially with the opposing arc contact 331, etc. The inner diameter of the cylinder cylindrical portion 421 is larger than the outer diameter of the gas circuit breaker movable current-carrying shaft 401, and the gas circuit breaker movable current-carrying shaft 401 is accommodated inside the cylinder cylindrical portion 421.

[0053] The cylinder bottom plate portion 422 is, for example, a disk-shaped plate-like body, and is provided at the end portion of the cylinder cylindrical portion 421 that is located on the driving side DS.

[0054] A rod through hole H422a through which the gas circuit breaker movable current-carrying shaft 401 passes is formed in the center of the cylinder bottom plate portion 422. The inner diameter of the rod through hole H422a is approximately the same as the outer diameter of the gas circuit breaker movable current-carrying shaft 401, and the gas circuit breaker movable current-carrying shaft 401 is fixed to the puffer cylinder 402 in a state where it passes through the rod through hole H422a. The cylinder bottom plate portion 422 and the gas circuit breaker movable current-carrying shaft 401 are electrically connected.

[0055] An exhaust hole H422b is formed in the cylinder bottom plate portion 422. The exhaust hole H422b is formed around the rod through-hole H422a so as to penetrate in the axial direction. Here, the exhaust hole H422b is configured to communicate with, for example, the rod through-hole H422a.

[0056] [B-3-2-3] Puffer Piston 403 The puffer piston 403 is housed inside the puffer cylinder 402. The puffer piston 403 is fixed to the grounded tank 200 via a cylinder support 406 and a piston support 407. The puffer piston 403 is, for example, an annular ring-shaped body, and is installed coaxially with the opposing arc contact 331, etc. The gas circuit breaker movable current-carrying shaft 401 passes through the inside of the puffer piston 403.

[0057] Here, the inner diameter of the puffer piston 403 is approximately the same as the outer diameter of the gas circuit breaker movable current-carrying shaft 401, and the gas circuit breaker movable current-carrying shaft 401 can slide in the axial direction relative to the puffer piston 403. In addition, the outer diameter of the puffer piston 403 is approximately the same as the inner diameter of the cylinder cylindrical portion 421 that constitutes the puffer cylinder 402, and the puffer cylinder 402 can slide in the axial direction relative to the puffer piston 403.

[0058] The puffer piston 403 defines the interior of the puffer cylinder 402 in the axial direction. Within the puffer cylinder 402, the space located on the drive side DS from the puffer piston 403 is the puffer chamber PR. The volume of the puffer chamber PR changes as the puffer cylinder 402 moves axially together with the gas circuit breaker movable current-carrying shaft 401. As the volume of the puffer chamber PR decreases, the pressure of the insulating gas inside the puffer chamber PR increases. Then, the insulating gas whose pressure has increased in the puffer chamber PR is released from the puffer chamber PR via the exhaust hole H422b of the puffer cylinder 402.

[0059] [B-3-2-4] Driving side contact portion 405 The driving side contact portion 405, together with the gas circuit breaker movable current-carrying shaft 401, is configured to slide in the axial direction by the operating mechanism 257, and the distance between it and the opposing side contact portion 303 varies.

[0060] Here, the drive-side contact portion 405 includes a drive-side arc contact 451 and a drive-side current-carrying contact 455 .

[0061] [B-3-2-4-1] Driving Side Arcing Contact 451 The driving side arcing contact 451 is, for example, a cylindrical tubular body, and is installed coaxially with the opposing side arcing contact 331 and the like.

[0062] Here, the driving side arc contactor 451 has approximately the same outer diameter and inner diameter as the movable current-carrying shaft hollow portion 412 constituting the gas circuit breaker moving current-carrying shaft 401. The driving side arc contactor 451 is coupled to an end portion located on the opposing side OS in the movable current-carrying shaft hollow portion 412, and is electrically connected to the gas circuit breaker moving current-carrying shaft 401. The driving side arc contactor 451 is configured to slide in the axial direction together with the gas circuit breaker moving current-carrying shaft 401 by an operating mechanism 257.

[0063] An end 451 a of the driving-side arcing contact 451 located on the opposing side OS protrudes radially inward, and the inner diameter of the end 451 a is the same as the outer diameter of the opposing-side arcing contact 331 .

[0064] The driving-side arcing contact 451 is configured so that the opposing-side arcing contact 331 is inserted therein in the energized state, and an arc discharge occurs between the driving-side arcing contact 451 and the opposing-side arcing contact 331 in the breaking process.

[0065] [B-3-2-4-2] Driving-side energized contactor 455 The driving-side energized contactor 455 is, for example, an annular ring-shaped body, and is installed coaxially with the opposing-side arcing contactor 331. The driving-side energized contactor 455 includes a portion that houses the driving-side arcing contactor 451 therein.

[0066] Here, the inner diameter of the driving side conductive contact 455 is larger than the outer diameter of the driving side arc contact 451. The outer diameter of the driving side conductive contact 455 is the same as the inner diameter of the end 335a of the opposing side conductive contact 335. The driving side conductive contact 455 is fixed to the cylinder bottom plate portion 422 of the puffer cylinder 402 so as to surround the driving side arc contact 451, and is electrically connected to the puffer cylinder 402. The driving side conductive contact 455 is configured to slide in the axial direction together with the gas circuit breaker movable conductive shaft 401 by the operation mechanism 257.

[0067] An end 455a of the driving-side conductive contact 455 located on the opposing side OS has, for example, a curved surface.

[0068] The driving-side conductive contact 455 is configured to be inserted into the opposing-side conductive contact 335 in a conducting state.

[0069] [B-3-2-5] Cylinder support 406 The cylinder support 406 is electrically connected to the puffer cylinder 402 and the electric wire EC1b. The cylinder support 406 is fixed to the grounded tank 200 and supports the puffer cylinder 402 so that the puffer cylinder 402 can slide in the axial direction.

[0070] Here, the cylinder support 406 includes a cylinder support cylindrical portion 461 and a cylinder support annular portion 462 .

[0071] The cylinder support cylindrical portion 461 is a cylindrical tubular body and is installed coaxially with the opposing arc contact 331, etc. The inner diameter of the cylinder support cylindrical portion 461 is larger than the outer diameter of the cylinder cylindrical portion 421 that constitutes the puffer cylinder 402.

[0072] The cylinder support annular portion 462 is an annular ring-shaped body and is installed coaxially with the opposing-side arc contact 331, etc. The cylinder support annular portion 462 is provided at the end of the cylinder support cylindrical portion 461 located on the opposing side OS, and is configured to protrude radially inward from the cylinder support cylindrical portion 461. Here, the cylinder support annular portion 462 is formed integrally with the cylinder support cylindrical portion 461. The inner diameter of the cylinder support annular portion 462 is the same as the outer diameter of the cylinder cylindrical portion 421 that constitutes the puffer cylinder 402.

[0073] A second ventilation hole H461 is formed in the cylinder support cylindrical portion 461. The second ventilation hole H461 is configured to penetrate the cylinder support cylindrical portion 461 in the radial direction.

[0074] [B-3-2-6] Piston Support 407 The piston support 407 is fixed to the cylinder support 406 and supports the puffer piston 403. The gas circuit breaker movable conducting shaft 401 passes through the inside of the piston support 407.

[0075] Here, the piston support 407 includes a piston support cylindrical portion 471 and a piston support annular portion 472 .

[0076] The piston support cylindrical portion 471 is a cylindrical tubular body, and is installed coaxially with the opposing side arc contact 331, etc. The outer diameter of the piston support cylindrical portion 471 is smaller than the outer diameter of the puffer piston 403, and the inner diameter of the piston support cylindrical portion 471 is larger than the outer diameter of the gas circuit breaker movable current-carrying shaft 401. The piston support cylindrical portion 471 has an end portion located on the opposing side OS connected to the puffer piston 403.

[0077] The piston support annular portion 472 is an annular ring-shaped body and is disposed coaxially with the opposing arc contact 331 and the like. The piston support annular portion 472 is provided at the end of the piston support cylindrical portion 471 located on the driving side DS. The outer diameter of the piston support annular portion 472 is smaller than the outer diameter of the piston support cylindrical portion 471, and the inner diameter of the piston support annular portion 472 is larger than the outer diameter of the gas circuit breaker movable current-carrying shaft 401. The outer diameter of the piston support annular portion 472 is the same as the inner diameter of the cylinder support cylindrical portion 461, and the piston support annular portion 472 is fixed to the cylinder support cylindrical portion 461. Here, the piston support annular portion 472 is formed integrally with the piston support cylindrical portion 471.

[0078] A third ventilation hole H471 is formed in the piston support cylindrical portion 471. The third ventilation hole H471 is configured to penetrate the piston support cylindrical portion 471 in the radial direction.

[0079] [B-3-2-7] Insulating Nozzle 500 The insulating nozzle 500 is made of an insulating material. The insulating nozzle 500 is a cylindrical tubular body, and is installed inside the grounded tank 200 coaxially with the opposing arc contact 331, etc.

[0080] The insulating nozzle 500 is fixed to the puffer cylinder 402 and is configured to move together with the puffer cylinder 402 and the driving side contact portion 405, etc., during the interruption process from an energized state (closed state) to an open state (open state).

[0081] The insulating nozzle 500 has a nozzle internal space S500 formed therein, and the nozzle internal space S500 accommodates the opposing side arcing contact 331 and the driving side arcing contact 451. The insulating nozzle 500 is also configured so that, when an arc discharge occurs between the opposing side contact portion 303 and the driving side contact portion 405 during the interruption process, insulating gas is released from the puffer chamber PR into the nozzle internal space S500.

[0082] The insulating nozzle 500 has a large diameter nozzle portion 510 , a small diameter nozzle portion 520 , and an inclined nozzle portion 530 .

[0083] The nozzle large diameter portion 510 is a portion of the insulating nozzle 500 that is located on the driving side DS, and is interposed between the driving side arcing contact 451 and the driving side current-carrying contact 455. The nozzle large diameter portion 510 includes a portion whose outer circumferential surface extends along the axial direction.

[0084] The small nozzle diameter section 520 is located on the opposing side OS of the large nozzle diameter section 510 in the insulating nozzle 500. The small nozzle diameter section 520 includes a portion whose outer peripheral surface extends along the axial direction. The outer diameter of the portion of the small nozzle diameter section 520 whose outer peripheral surface extends along the axial direction is smaller than the outer diameter of the large nozzle diameter section 510.

[0085] The nozzle inclined portion 530 is located closer to the opposing side OS than the nozzle small diameter portion 520 in the insulating nozzle 500. The nozzle inclined portion 530 includes a portion whose outer peripheral surface is inclined with respect to the axial direction so that the outer diameter increases from the nozzle small diameter portion 520 toward the opposing side OS. An end portion 530a of the nozzle inclined portion 530 located on the opposing side OS protrudes outward in the radial direction, and the outer diameter of the end portion 530a is smaller than the inner diameter of the opposing side conductive contact 335.

[0086] [B-4] Control Unit 800 As shown in FIG. 2A, the cutoff device 100 also includes a control unit 800 in addition to the above components.

[0087] The control unit 800 includes an arithmetic unit (not shown) and a memory device (not shown), and is configured to control the operation of each part that constitutes the shutdown device 100, for example, by a high-speed sequence, by the arithmetic unit performing arithmetic processing using a program stored in the memory device.

[0088] The control unit 800 outputs control signals to the operation mechanisms 217 and 257 based on, for example, commands input from the outside, and controls the operations of the operation mechanisms 217 and 257. As a result, the control unit 800 executes an electric circuit interruption operation that changes the electric circuit EC from a conducting state to a cut-off state, and an electric circuit closing operation that changes the electric circuit EC from a cut-off state to a conducting state.

[0089] When performing an electric circuit breaking operation, the control unit 800 controls the operation of the operation mechanism 217 and the operation mechanism 257 so as to switch the energized contact 101, the first breaking contact 111, and the second breaking contact 112 from a closed state to an open state. When performing an electric circuit closing operation, the control unit 800 controls the operation of the operation mechanism 217 and the operation mechanism 257 so as to switch the energized contact 101, the first breaking contact 111, and the second breaking contact 112 from an open state to a closed state.

[0090] [C] Operation of the Breaker Device 100 FIGS. 3A, 3B, and 3C are circuit diagrams showing the operation of the breaker device 100 according to the first embodiment.

[0091] 3A, 3B, and 3C, along with Fig. 1, show the state when an electrical circuit closing operation is performed in the circuit breaker 100. In each figure, an electrically insulated state of each contact is shown as an open state (indicated as "Open" in the figures), and an electrically connected state of each contact is shown as a closed state (indicated as "Close" in the figures).

[0092] When the circuit closing operation is performed in the circuit breaker 100 of this embodiment, the circuit EC goes from the interrupted state (fully open state) shown in Fig. 1 through the closing process shown in Fig. 3A, 3B, and 3C, to a conducting state, and current flows through the circuit EC. That is, in the circuit closing operation, as shown in Fig. 3A, 3B, and 3C, a first breaking contact closing operation (ST1), a second breaking contact closing operation (ST2), and a conducting contact closing operation (ST3) are performed in sequence.

[0093] The circuit closing operation will be described in detail below.

[0094] [C-1] Breaking State In the breaking state before the current circuit closing operation is performed, as shown in FIG. 1, the first breaking contact 111, the second breaking contact 112, and the conducting contact 101 are in the open state.

[0095] Specifically, in the vacuum circuit breaker 211, the movable electrode 111A and the fixed electrode 111B housed inside the vacuum vessel 212 as the first breaking contact 111 are separated from each other and are electrically insulated, thereby bringing the first breaking contact 111 into an open state. Also, in the gas circuit breaker 251, the driving-side conductive contact 455 and the opposing-side conductive contact 335 constituting the current-carrying contact 101 are separated from each other and are electrically insulated, thereby bringing the current-carrying contact 101 into an open state. Furthermore, in the gas circuit breaker 251, the driving-side arcing contact 451 and the opposing-side arcing contact 331 constituting the second breaking contact 112 are separated from each other and are electrically insulated, thereby bringing the second breaking contact 112 into an open state (see FIG. 2A ).

[0096] As a result, in the interrupted state, the current is interrupted in both the energizing electric circuit EC1 and the interrupting electric circuit EC2 of the electric circuit EC (see FIG. 1). Note that in the gas circuit breaker 251, the energizing contact 101 and the second interrupting contact 112 have a voltage resistance that can withstand the operating voltage before the electric circuit closing operation is performed.

[0097] [C-2] Closing Process [C-2-1] First Breaker Contact Closing Operation (ST1) In the circuit closing operation, the first breaker contact closing operation (ST1) is first executed as shown in Fig. 3A. In the first breaker contact closing operation (ST1), the first breaker contact 111 switches from an open state to a closed state.

[0098] Although not shown, in the first breaking contact closing operation (ST1), in the vacuum circuit breaker 211, the movable electrode 111A and the fixed electrode 111B housed inside the vacuum vessel 212 as the first breaking contact 111 approach each other and become electrically connected (see FIG. 2A ). Note that in the gas circuit breaker 251, the current-carrying contact 101 and the second breaking contact 112 have the withstand voltage performance to withstand the operating voltage even after the first breaking contact closing operation (ST1) is completed.

[0099] [C-2-2] Second Breaker Contact Closing Operation (ST2) Next, in the electrical circuit closing operation, the second breaker contact closing operation (ST2) is executed as shown in Fig. 3B. In the second breaker contact closing operation (ST2), the second breaker contact 112 switches from an open state to a closed state.

[0100] FIG. 4A is a cross-sectional view showing a state when the second breaking contact closing operation (ST2) is performed in the gas circuit breaker 251 constituting the circuit breaker 100 according to the first embodiment.

[0101] As shown in FIG. 4A , in the second breaking contact closing operation (ST2), in the gas circuit breaker 251, the driving side arc contact 451 and the opposing side arc contact 331 constituting the second breaking contact 112 approach each other and are electrically connected.

[0102] Specifically, when the second breaking contact closing operation (ST2) is performed, in the gas circuit breaker 251, the gas circuit breaker movable current-carrying shaft 401 moves from the driving side DS to the opposing side OS, causing the driving-side arcing contact 451 to approach the opposing-side arcing contact 331. At this time, a pre-arcing discharge AR occurs inside the insulating nozzle 500 between the opposing-side arcing contact 331 and the driving-side arcing contact 451. The pre-arcing discharge AR brings the opposing-side arcing contact 331 and the driving-side arcing contact 451 into an electrically connected state.

[0103] Upon completion of the first breaking contact closing operation (ST1) and the second breaking contact closing operation (ST2), the first breaking contact 111 is closed and the second breaking contact 112 is closed, causing current to flow through the breaking circuit EC2 in which the first breaking contact 111 and the second breaking contact 112 are installed (see Figure 3B).

[0104] [C-2-3] Contact Closing Operation (ST3) Next, in the circuit closing operation, contact closing operation (ST3) is executed as shown in Fig. 3C. In contact closing operation (ST3), contact 101 is switched from the open state to the closed state.

[0105] FIG. 4B is a cross-sectional view showing a state when the energizing contact closing operation (ST3) is performed in the gas circuit breaker 251 constituting the circuit breaker 100 according to the first embodiment.

[0106] As shown in Figure 4B, in the energizing contact closing operation (ST3), in the gas circuit breaker 251, the driving side energizing contact 455 and the opposing side energizing contact 335 that constitute the energizing contact 101 approach each other and become electrically connected, thereby switching the energizing contact 101 to a closed state.

[0107] Specifically, when the energizing contact closing operation (ST3) is performed, in the gas circuit breaker 251, the gas circuit breaker movable energizing shaft 401 moves further from the driving side DS to the opposing side OS, causing the driving side arcing contact 451 to come into contact with the opposing side arcing contact 331, and then the opposing side energizing contact 335 and the driving side energizing contact 455 come closer to each other. Then, as the gas circuit breaker movable energizing shaft 401 moves further from the driving side DS to the opposing side OS, the opposing side energizing contact 335 and the driving side energizing contact 455 come into contact with each other and are electrically connected.

[0108] As described above, in the circuit breaker 100 of this embodiment, the energizing contact 101, the first breaking contact 111, and the second breaking contact 112 are switched to a closed state, thereby switching the electric circuit EC to an energized state. As described above, in this embodiment, the energizing contact 101 is configured to have a lower resistance than the first breaking contact 111 and the second breaking contact 112. Therefore, after the energizing contact closing operation (ST3) is completed, a larger current flows in the energizing electric circuit EC1, in which the energizing contact 101 is installed, than in the breaking electric circuit EC2, in which the first breaking contact 111 and the second breaking contact 112 are installed. In other words, commutation occurs (see FIG. 3C ).

[0109] [D] Details of the Power Line Closing Operation The power line closing operation performed in this embodiment will be described in further detail.

[0110] FIG. 5 is a diagram showing the circuit closing operations (first breaking contact closing operation (ST1), second breaking contact closing operation (ST2), and energizing contact closing operation (ST3)) performed in the first embodiment.

[0111] 5, the horizontal axis represents time, and the vertical axis represents the state of each contact (the energizing contact 101, the first breaking contact 111, and the second breaking contact 112). In Fig. 5, the open state (electrically insulated state) of each contact is represented as "Open," and the closed state (electrically connected state) of each contact is represented as "Close" (the dashed lines indicate a transition from the open state to the closed state). In Fig. 5, the time when the closing operation of each contact starts (the time when the pair of contacts (electrodes) start to approach each other) is represented as "START," the time when the closing operation of each contact is completed (the time when the pair of contacts (electrodes) switch to an electrically connected state) is represented as "END," and the period during which a pre-arc discharge occurs is represented as "ARC."

[0112] 5 , the first breaking contact closing operation (ST1) starts at a start time t111s and completes at a completion time t111e, switching the first breaking contact 111 from an open state to a closed state. The second breaking contact closing operation (ST2) starts at a start time t112s and completes at a completion time t112e, switching the second breaking contact 112 from an open state to a closed state. The energizing contact closing operation (ST3) starts at a start time t101s and completes at a completion time t101e, switching the energizing contact 101 from an open state to a closed state. Note that the completion time t112e of the second breaking contact closing operation (ST2) is the time when a pre-arc discharge AR occurs between the opposing-side arcing contact 331 and the driving-side arcing contact 451 that constitute the second breaking contact 112, and the two are electrically connected. After the completion time t112e of the second breaking contact closing operation (ST2), by the time of extinguishing the pre-arc discharge AR at the extinguishing time t112a, the opposing side arc contact 331 and the driving side arc contact 451 constituting the second breaking contact 112 are physically connected to each other, and the electrical connection between them is maintained (see FIG. 4A).

[0113] In this embodiment, the start time t111s of the first breaking contact closing operation (ST1) is before the start time t112s of the second breaking contact closing operation (ST2). Here, the start time t111s of the first breaking contact closing operation (ST1) is before the start time t112s of the second breaking contact closing operation (ST2). Also, the completion time t111e of the first breaking contact closing operation (ST1) is before the completion time t112e of the second breaking contact closing operation (ST2). Here, the completion time t111e of the first breaking contact closing operation (ST1) is after the start time t112s of the second breaking contact closing operation (ST2) but before the completion time t112e of the second breaking contact closing operation (ST2).

[0114] In this embodiment, the start time t112s of the second breaking contact closing operation (ST2) is before the completion time t111e of the first breaking contact closing operation (ST1). The completion time t112e of the second breaking contact closing operation (ST2) is before the completion time t101e of the energizing contact closing operation (ST3).

[0115] In this embodiment, the start time t101s of the energizing contact closing operation (ST3) is the same as the start time t112s of the second breaking contact closing operation (ST2). Here, the start time t101s of the energizing contact closing operation (ST3) is later than the completion time t111e of the first breaking contact closing operation (ST1) and earlier than the completion time t112e of the second breaking contact closing operation (ST2). The completion time t101e of the energizing contact closing operation (ST3) is later than the extinction time t112a at which the pre-arc discharge AR at the second breaking contact 112 is extinguished. The start time t101s of the energizing contact closing operation (ST3) does not have to be the same as the start time t112s of the second breaking contact closing operation (ST2). In other words, the gas circuit breaker 251 may be configured so that the driving-side arcing contact 451 and the driving-side energizing contact 455 move independently of each other.

[0116] [E] Summary As described above, the circuit breaker 100 of this embodiment has the current-carrying contact 101, the first breaking contact 111, and the second breaking contact 112. The first breaking contact 111 is connected in parallel with the current-carrying contact 101, and the second breaking contact 112 is connected in parallel with the current-carrying contact 101 and in series with the first breaking contact 111. The first breaking contact 111 is configured by a vacuum circuit breaker 211 that switches between a closed state and an open state inside a vacuum container 212. The second breaking contact 112 and the current-carrying contact 101 are configured by a gas circuit breaker 251 that switches between a closed state and an open state inside an insulating gas container 202 filled with insulating gas.

[0117] In the circuit breaker 100 of this embodiment, the energizing contact 101 is configured as a gas circuit breaker 251, so sufficient current-carrying performance can be obtained in the energized state. Therefore, in the circuit breaker 100 of this embodiment, the vacuum circuit breaker 211 configuring the first breaking contact 111 does not need to have improved current-carrying performance, so it is possible to switch from a closed state to an open state more quickly and obtain sufficient voltage-resistance performance. Furthermore, in the circuit breaker 100 of this embodiment, the first breaking contact 111 configured as a vacuum circuit breaker 211 is used to finally reach the interrupted state. Therefore, the gas circuit breaker 251 configuring the energizing contact 101 and the second breaking contact 112 is made of SF, which has high performance such as insulation performance and arc-extinguishing performance. ６ In addition to being able to reduce gas consumption, ６ A gas having a lower greenhouse effect potential than the gas can be used as the insulating gas.

[0118] As described above, in this embodiment, when performing the circuit closing operation, a first breaking contact closing operation (ST1) is performed to change the first breaking contact 111 from an open state to a closed state, a second breaking contact closing operation (ST2) is performed to change the second breaking contact 112 from an open state to a closed state, and a current-carrying contact closing operation (ST3) is performed to change the current-carrying contact 101 from an open state to a closed state.

[0119] In this embodiment, the completion time t111e of the first breaking contact closing operation (ST1) occurs before the completion time t112e of the second breaking contact closing operation (ST2), which occurs before the completion time t101e of the energizing contact closing operation (ST3) (see FIG. 5).

[0120] As described above, in the first breaking contact closing operation (ST1) of this embodiment, when the second breaking contact 112 is in the open state, the first breaking contact 111 switches from the open state to the closed state. That is, when the movable electrode 111A and the fixed electrode 111B constituting the first breaking contact 111 in the vacuum circuit breaker 211 approach each other and transition to an electrically connected state, the opposing-side arc contact 331 and the driving-side arc contact 451 constituting the second breaking contact 112 maintain an electrically insulated state (see FIGS. 2A and 3A ). Therefore, in the first breaking contact closing operation (ST1), no current flows through the breaking electrical circuit EC2. Therefore, even when the movable electrode 111A and the fixed electrode 111B constituting the vacuum circuit breaker 211 approach each other, no pre-arc discharge occurs between the movable electrode 111A and the fixed electrode 111B. Therefore, in this embodiment, even if the movable electrode 111A and the fixed electrode 111B that constitute the vacuum circuit breaker 211 come into contact with each other after the completion of the first breaking contact closing operation (ST1), the two are not welded together by a pre-arc discharge. As a result, even when the breaking operation that changes the vacuum circuit breaker 211 from the closed state to the open state is performed and the movable electrode 111A and the fixed electrode 111B are separated from each other, the surfaces of the movable electrode 111A and the fixed electrode 111B are not roughened, and therefore the withstand voltage performance of the vacuum circuit breaker 211 is not reduced.

[0121] Therefore, the circuit breaker 100 of this embodiment can have sufficient voltage-resistance performance even when using the vacuum circuit breaker 211. When the second breaking contact closing operation (ST2) is performed, a pre-arc discharge occurs between the opposing side arcing contact 331 and the driving side arcing contact 451 that constitute the second breaking contact 112, but unlike the case of the vacuum circuit breaker 211, no deterioration in voltage-resistance performance occurs. Compared to the vacuum circuit breaker 211, the gas circuit breaker 251 has less effect on voltage-resistance performance due to the contact surface roughness, so there is no problem even if a pre-arc discharge occurs on the gas circuit breaker 251 side.

[0122] In this embodiment, the start time t112s of the second breaking contact closing operation (ST2) is earlier than the completion time t111e of the first breaking contact closing operation (ST1). Therefore, the circuit breaking device 100 of this embodiment can shorten the execution time of the circuit closing operation.

[0123] [F] Modifications Modifications of this embodiment will be described.

[0124] [F-1] Modification 1-1 Fig. 6 is a diagram showing the circuit closing operations (first breaking contact closing operation (ST1), second breaking contact closing operation (ST2), and energizing contact closing operation (ST3)) performed in Modification 1-1 of the first embodiment. In Fig. 6, as in Fig. 5, the horizontal axis represents time, and the vertical axis represents the state of each contact (energizing contact 101, first breaking contact 111, second breaking contact 112).

[0125] 6, in the circuit closing operation of this modification, the completion time t111e of the first breaking contact closing operation (ST1) is the same as the completion time t112e of the second breaking contact closing operation (ST2). In other words, in this modification, the first breaking contact 111 and the second breaking contact 112 are simultaneously switched from the open state to the closed state, and current flows through the breaking circuit EC2 at the completion time t111e of the first breaking contact closing operation (ST1) and the completion time t112e of the second breaking contact closing operation (ST2).

[0126] 6, at completion time t111e of the first breaking contact closing operation (ST1), a pre-arc discharge occurs between the movable electrode 111A and the fixed electrode 111B that constitute the first breaking contact 111 in the vacuum circuit breaker 211, and the two are electrically connected to each other. Therefore, when the movable electrode 111A and the fixed electrode 111B come into contact with each other thereafter, the movable electrode 111A and the fixed electrode 111B may be welded to each other by the pre-arc discharge.

[0127] However, as shown in Figure 6, at the completion time t112e of the second breaking contact closing operation (ST2), which is the same time as the completion time t111e of the first breaking contact closing operation (ST1), in the gas circuit breaker 251, a pre-arc discharge also occurs between the driving side arc contact 451 and the opposing side arc contact 331 that constitute the second breaking contact 112, and the two are electrically connected to each other.

[0128] As described above, in this modification, a pre-arc discharge occurs simultaneously at the first breaking contact 111 and the second breaking contact 112. Therefore, in this modification, the voltage (shared voltage) applied to the first breaking contact 111 when a current flows through the interrupting electric circuit EC2 is lower than when a current flows only through the first breaking contact 111 in the interrupting electric circuit EC2. Similarly, the time it takes for a pre-arc discharge to occur and disappear at the first breaking contact 111 is shorter than when a current flows only through the first breaking contact 111 in the interrupting electric circuit EC2. As a result, damage to the first breaking contact 111 is reduced compared to when a current flows only through the first breaking contact 111 in the interrupting electric circuit EC2.

[0129] Therefore, in this modified example, the breakdown voltage performance of the circuit breaker 100 can be sufficiently maintained.

[0130] [F-2] Modification 1-2 It is preferable that the closing speed at which the first breaking contact 111 is changed from an open state to a closed state in the first breaking contact closing operation (ST1) is lower than the closing speed at which the second breaking contact 112 is changed from an open state to a closed state in the second breaking contact closing operation (ST2) and the closing speed at which the energizing contact 101 is changed from an open state to a closed state in the energizing contact closing operation (ST3).

[0131] If the closing speed of the first breaking contact 111 is high, chattering (microscopic mechanical vibration) may occur in the vacuum circuit breaker 211 including the first breaking contact 111. Therefore, if chattering occurs in the vacuum circuit breaker 211 including the first breaking contact 111 during execution of the second breaking contact closing operation (ST2), a pre-arc discharge may occur in the first breaking contact 111. However, by making the closing speed of the first breaking contact 111 slower than the closing speed of the second breaking contact 112 and the closing speed of the conducting contact 101, it is possible to suppress the occurrence of chattering in the vacuum circuit breaker 211.

[0132] Second Embodiment [A] Details of the Electrical Circulation Closing Operation Fig. 7 is a diagram showing the electrical circuit closing operations (first breaking contact closing operation (ST1), second breaking contact closing operation (ST2), and energizing contact closing operation (ST3)) performed in the second embodiment. In Fig. 7, similar to Fig. 5, the horizontal axis represents time, and the vertical axis represents the state of each contact (energizing contact 101, first breaking contact 111, second breaking contact 112).

[0133] In this embodiment, as shown in Fig. 7, a part of the circuit closing operation is different from that in the first embodiment (see Fig. 5). Except for this point and related matters, the circuit breaking device 100 of this embodiment is the same as that in the first embodiment. Therefore, explanations of overlapping matters will be omitted as appropriate.

[0134] 7, in the current circuit closing operation of this embodiment, unlike the first embodiment (see FIG. 5), the start time t112s of the second breaking contact closing operation (ST2) and the start time t101s of the energizing contact closing operation (ST3) are after the completion time t111e of the first breaking contact closing operation (ST1). That is, in this embodiment, after the first breaking contact 111 switches from the open state to the closed state upon completion of the first breaking contact closing operation (ST1), the second breaking contact closing operation (ST2) and the energizing contact closing operation (ST3) are started, and as the second breaking contact 112 transitions from the open state to the closed state, the energizing contact 101 transitions from the open state to the closed state.

[0135] In this embodiment, the device includes a detection unit (not shown) such as a contact that outputs a signal when the first blocking contact 111 switches from an open state to a closed state, and the control unit 800 transitions the second blocking contact 112, etc. from an open state to a closed state in response to the signal output by the detection unit.

[0136] [B] Summary As described above, in this embodiment, since the second breaking contact closing operation (ST2) is not started before the first breaking contact closing operation (ST1) is completed, it is possible to reliably prevent current from flowing through the breaking electric circuit EC2 during the first breaking contact closing operation (ST1). As a result, in this embodiment, it is possible to reliably prevent pre-arc discharge from occurring between the movable electrode 111A and the fixed electrode 111B that constitute the first breaking contact 111 in the vacuum circuit breaker 211, and therefore the withstand voltage performance of the vacuum circuit breaker 211 is not reduced.

[0137] Therefore, the circuit breaker 100 of this embodiment can have a more sufficient withstand voltage performance even when the vacuum circuit breaker 211 is used.

[0138] Third Embodiment [A] Detailed Configuration of the Circuit Breaker 100 Fig. 8A is a cross-sectional view schematically illustrating the configuration of the circuit breaker 100 according to the third embodiment. Fig. 8A shows the circuit breaker 100 in a circuit breaker state, similar to Fig. 2A.

[0139] As shown in Fig. 8A, the shutoff device 100 of this embodiment differs from the first embodiment (see Fig. 2A) in that it is not provided with an operating mechanism 217. Except for this point and related matters, the shutoff device 100 of this embodiment is similar to the first embodiment. Therefore, explanations of overlapping matters will be omitted as appropriate.

[0140] As shown in Figure 8A, in the circuit breaking device 100 of this embodiment, the operating mechanism 257 is configured to operate the current-carrying contact 101 and the second circuit breaking contact 112, similar to the case of the first embodiment (see Figure 2A).

[0141] However, in the circuit breaking device 100 of this embodiment, the operating mechanism 257 is further configured to operate the first breaking contact 111. Here, the operating mechanism 257 is connected to the insulating rod 216 via an operating link L216, and is configured to switch the first breaking contact 111 between a closed state and an open state by operating the insulating rod 216.

[0142] [B] Details of the current circuit closing operation Figure 8B is a diagram showing the current circuit closing operations (first breaking contact closing operation (ST1), second breaking contact closing operation (ST2), and energizing contact closing operation (ST3)) performed in the third embodiment. In Figure 8B, as in Figure 5, the horizontal axis represents time, and the vertical axis represents the state of each contact (energizing contact 101, first breaking contact 111, and second breaking contact 112).

[0143] 8B , in the current circuit closing operation of this embodiment, as in the first embodiment (see FIG. 5 ), the completion time t111e of the first breaking contact closing operation (ST1) is before the completion time t112e of the second breaking contact closing operation (ST2), and the completion time t112e of the second breaking contact closing operation (ST2) is before the completion time t101e of the energizing contact closing operation (ST3).

[0144] However, as shown in Fig. 8B , in the current circuit closing operation of this embodiment, unlike the first embodiment (see Fig. 5 ), the start time t111s of the first breaking contact closing operation (ST1), the start time t112s of the second breaking contact closing operation (ST2), and the start time t101s of the energizing contact closing operation (ST3) are the same. That is, in this embodiment, the first breaking contact closing operation (ST1), the second breaking contact closing operation (ST2), and the energizing contact closing operation (ST3) are started simultaneously.

[0145] [C] Summary As described above, in the circuit breaking device 100 of this embodiment, the operating mechanism 257 operates the energized contact 101, the first breaking contact 111, and the second breaking contact 112, and is configured so that the first breaking contact closing operation (ST1), the second breaking contact closing operation (ST2), and the energized contact closing operation (ST3) are started simultaneously.

[0146] Therefore, in this embodiment, it is possible to obtain the same effects as those of the first embodiment with a simplified device.

[0147] [D] Modifications In the above embodiment, the first breaking contact closing operation (ST1), the second breaking contact closing operation (ST2), and the energizing contact closing operation (ST3) are simultaneously initiated by operating the operation mechanism 257. However, this is not limiting. For example, the operation mechanism 257 may be configured so that the second breaking contact closing operation (ST2) and the energizing contact closing operation (ST3) are initiated after the first breaking contact closing operation (ST1) is initiated.

[0148] Fourth Embodiment [A] Detailed Configuration of Circuit Breaker 100 FIG. 9 is a cross-sectional view schematically showing the configuration of a vacuum circuit breaker 211 including a first interrupting contact 111 in a circuit breaker according to a fourth embodiment.

[0149] In this embodiment, the vacuum circuit breaker 211 has a partially different configuration from that of the first embodiment (see FIG. 2A), as shown in FIG. 9. Except for this and related points, the circuit breaker 100 of this embodiment is the same as that of the first embodiment. Therefore, explanations of overlapping points will be omitted as appropriate.

[0150] 9, in the vacuum circuit breaker 211 of this embodiment, a spring SP216 is provided on the vacuum circuit breaker fixed current-carrying shaft 213. The vacuum circuit breaker 211 of this embodiment is configured such that when the first breaking contact 111 is in the closed state, the spring force of the spring SP216 presses the movable electrode 111A against the fixed electrode 111B, causing them to come into close contact.

[0151] [B] Summary As described above, in the present embodiment, after the first breaking contact closing operation (ST1) is completed (the first breaking contact 111 is in the closed state), the spring force of the spring SP216 in the vacuum circuit breaker 211 brings the movable electrode 111A into close contact with the fixed electrode 111B, reliably maintaining the first breaking contact 111 in the closed state. Therefore, in the present embodiment, when the second breaking contact closing operation (ST2) is being performed after the first breaking contact closing operation (ST1), chattering does not occur in the vacuum circuit breaker 211, and pre-arc discharge between the movable electrode 111A and the fixed electrode 111B can be prevented. As a result, the circuit breaker 100 of the present embodiment can effectively prevent a decrease in the withstand voltage performance of the vacuum circuit breaker 211.

[0152] Therefore, the circuit breaker 100 of this embodiment can have a more sufficient withstand voltage performance even when the vacuum circuit breaker 211 is used.

[0153] <Others> Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are intended to be included within the scope and spirit of the invention, as well as within the scope of the inventions and their equivalents as set forth in the claims.

[0154] 3: opposing side unit, 4: driving side unit, 100: circuit breaker, 101: current-carrying contact, 111: first breaking contact, 111A: movable electrode, 111B: fixed electrode, 112: second breaking contact, 200: grounding tank, 202: insulating gas container, 211: vacuum circuit breaker, 212: vacuum container, 212a: porcelain tube, 212b: flange, 213: vacuum circuit breaker fixed current-carrying shaft, 214: vacuum circuit breaker movable current-carrying shaft, 215: bellows, 216: insulating rod, 217: operating mechanism, 218: arc shield, 251: gas Gas circuit breaker, 253: gas circuit breaker fixed current-carrying shaft, 256: insulating rod, 257: operating mechanism, 301: cooling cylinder, 302: support portion, 303: opposing contact portion, 321: support ring portion, 322: support protrusion portion, 331: opposing arc contact, 331a: end portion, 335: opposing current-carrying contact, 335a: end portion, 401: gas circuit breaker movable current-carrying shaft, 402: puffer cylinder, 403: puffer piston, 405: driving side contact portion, 406: cylinder support, 407: piston support , 411: solid portion of movable current-carrying shaft, 412: hollow portion of movable current-carrying shaft, 421: cylindrical portion of cylinder, 422: bottom plate portion of cylinder, 451: driving side arc contact, 451a: end portion, 455: driving side current-carrying contact, 455a: end portion, 461: cylindrical portion of cylinder support, 462: annular portion of cylinder support, 471: cylindrical portion of piston support, 472: annular portion of piston support, 500: insulating nozzle, 510: large diameter portion of nozzle, 520: small diameter portion of nozzle, 530: inclined portion of nozzle, 530a: end portion, 800 : control unit, DS: drive side, EC: electrical circuit, EC1: energizing electrical circuit, EC2: interrupting electrical circuit, H412: first ventilation hole, H422a: rod through hole, H422b: exhaust hole, H461: second ventilation hole, H471: third ventilation hole, L216: operation link, OS: opposite side, PR: puffer chamber, R: pre-arc discharge AR, S500: nozzle internal space, SL214: sliding part, SP: support part, SP216: spring, ST1: first breaking contact closing operation, ST2: second breaking contact closing operation, ST3: energizing contact closing operation

Claims

1. A circuit breaker comprising: an energizing contact; a first breaking contact connected in parallel with the energizing contact; and a second breaking contact connected in parallel with the energizing contact and in series to the first breaking contact, wherein the first breaking contact is constituted by a vacuum circuit breaker which switches between a closed state and an open state inside a vacuum container; and the second breaking contact and the energizing contact are constituted by gas circuit breakers which switch between a closed state and an open state inside an insulating gas container filled with insulating gas; when executing an electric circuit closing operation which changes an electric circuit from an interrupted state to an energized state, a first breaking contact closing operation which changes the first breaking contact from an open state to a closed state, a second breaking contact closing operation which changes the second breaking contact from an open state to a closed state, and an energizing contact closing operation which changes the energizing contact from an open state to a closed state are executed, wherein the completion point of the first breaking contact closing operation is before the completion point of the second breaking contact closing operation, and the completion point of the second breaking contact closing operation is before the completion point of the energizing contact closing operation, a current flows through the first breaking contact and the second breaking contact when the first breaking contact closing operation and the second breaking contact closing operation are completed, and a current flows through the current-carrying contact greater than through the first breaking contact and the second breaking contact when the energizing contact closing operation is completed.

2. The circuit breaker according to claim 1, wherein the second circuit breaker contact closing operation starts before the first circuit breaker contact closing operation is completed.

3. The circuit breaker according to claim 1, wherein a time point at which the first circuit breaker contact closing operation is completed is the same as a time point at which the second circuit breaker contact closing operation is completed.

4. The circuit breaker according to claim 1, wherein the start time of the second circuit breaker contact closing operation is later than the completion time of the first circuit breaker contact closing operation.

5. The circuit breaker according to claim 1, wherein a start time of the first circuit breaker contact closing operation is the same as a start time of the second circuit breaker contact closing operation.

6. The circuit breaker according to claim 1, further comprising an operating mechanism for operating said current-carrying contact, said first circuit breaker contact, and said second circuit breaker contact.

7. The circuit breaker device as described in claim 1, wherein a closing speed at which the first breaking contact is changed from an open state to a closed state in the first breaking contact closing operation is lower than a closing speed at which the second breaking contact is changed from an open state to a closed state in the second breaking contact closing operation and a closing speed at which the current-carrying contact is changed from an open state to a closed state in the current-carrying contact closing operation.

8. The circuit breaker according to claim 1, wherein the vacuum circuit breaker includes a movable electrode mounted on a vacuum circuit breaker movable current shaft, and a fixed electrode mounted on a vacuum circuit breaker fixed current shaft arranged coaxially with the vacuum circuit breaker movable current shaft, and is configured to be in a closed state when the movable electrode and the fixed electrode are in an electrically connected state, and to be in an open state when the movable electrode and the fixed electrode are in an electrically insulated state, and wherein a spring is mounted on the vacuum circuit breaker fixed current shaft, and when the first circuit breaker contact is in a closed state, the movable electrode is pressed against the fixed electrode by the spring force of the spring and is in close contact with the fixed electrode.

9. A circuit breaker as claimed in any one of claims 1 to 8, wherein the gas circuit breaker includes: a gas circuit breaker movable current shaft on which a driving side arc contactor and a driving side current contactor are provided; and a gas circuit breaker fixed current shaft which is aligned coaxially with the gas circuit breaker movable current shaft and on which an opposing side arc contactor and an opposing side current contactor are provided, wherein the current contacts are configured to be in a closed state when the driving side current contactor and the opposing side current contactor are in a connected state, and to be in an open state when the driving side current contactor and the opposing side current contactor are in an insulated state, and wherein the second breaking contact is configured to be in a closed state when the driving side arc contactor and the opposing side arc contactor are in a connected state, and to be in an open state when the driving side arc contactor and the opposing side arc contactor are in an insulated state.

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