Gas-insulated switchgear

Abstract

The gas-insulated switchgear (100) includes a tank (1) filled with insulating gas and having an internal current path connecting a first outer conductor (15) that receives a direct current and a second outer conductor (16) that outputs a direct current, a first circuit-breaking unit (10) and a second circuit-breaking unit (20) that are installed on the current path within the tank (1), and a resistor (70) that is installed in parallel with the second circuit-breaking unit (20). In a closing operation, only the first circuit-breaking unit (10) is first brought into a closed state, and after a preset time has elapsed, the first circuit-breaking unit (10) and the second circuit-breaking unit (20) are brought into a closed state.

Description

[Technical Field]

[0001] The present disclosure relates to a gas-insulated switchgear used to interrupt direct current. [Background technology]

[0002] In conventional DC transmission systems, a resistor is installed in parallel with the main circuit, and a bypass switch is installed in the main circuit. The bypass switch is then opened to allow current to flow through the resistor, and trial charging is then performed before operation begins.

[0003] Furthermore, DC transmission systems are equipped with DC circuit breakers that cut off current when a fault occurs. As disclosed in Patent Document 1, DC circuit breakers generally include separate devices that constitute a core circuit breaker that cuts off fault currents and a residual current circuit breaker that cuts off residual currents.

[0004] Therefore, in order to enable test charging and current interruption in the event of an accident in a DC transmission system, it is necessary to install equipment that constitutes a core circuit breaker, equipment that constitutes a residual current circuit breaker, resistors, and bypass switches. In a typical DC transmission system, DC equipment on the transmitting side, equipment that constitutes the core circuit breaker, equipment that constitutes the residual current circuit breaker, resistors and bypass switches, and DC equipment on the receiving side are installed in this order. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 47-4380 Summary of the Invention [Problem to be solved by the invention]

[0006] However, when the DC circuit breaker disclosed in Patent Document 1 is applied to a DC transmission system, it is necessary to install a device constituting the core circuit breaking unit, a device constituting the residual current circuit breaking unit, a resistor, and a bypass switch, which requires a large installation area.

[0007] For this reason, there is a demand for reducing the installation area of ​​devices in DC transmission systems that perform test charging and cut off current in the event of an accident.

[0008] The present disclosure has been made in consideration of the above, and aims to provide a gas-insulated switchgear that can reduce the installation area of ​​a group of devices that interrupt current during test charging and when an accident occurs in a DC transmission system. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems and achieve the object, the gas-insulated switchgear according to the present disclosure includes a tank filled with insulating gas and having an internal current path connecting a first outer conductor that receives DC current and a second outer conductor that outputs DC current, a first circuit breaker and a second circuit breaker installed on the current path within the tank, and a resistor installed in parallel with the second circuit breaker. In a closing operation, only the first circuit breaker is first brought into a closed state, and after a preset time has elapsed, the first and second circuit breakers are brought into a closed state. [Effects of the Invention]

[0010] According to the present disclosure, it is possible to obtain an advantageous effect of providing a gas-insulated switchgear that can reduce the installation area of ​​a group of devices that interrupt current during test charging and when an accident occurs in a DC transmission system. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing the configuration of a DC power transmission system using a gas-insulated switchgear according to a first embodiment. [Figure 2] 1 is a cross-sectional view of the gas-insulated switchgear according to the first embodiment when the first and second circuit breakers are in a circuit breaker state; [Figure 3] 1 is a cross-sectional view of the gas-insulated switchgear according to the first embodiment when the first circuit-breaking unit is in a closed state and the second circuit-breaking unit is in a circuit-breaking state; [Figure 4] 1 is a cross-sectional view of the gas-insulated switchgear according to the first embodiment when the first and second circuit-breaking units are in a closed state; [Figure 5] 10 is a cross-sectional view of the gas-insulated switchgear according to the second embodiment when the first and second circuit breakers are in a circuit breaker state. [Figure 6] 10 is a cross-sectional view of the gas-insulated switchgear according to the third embodiment when the first and second circuit breakers are in a circuit breaker state. [Figure 7] 10 is a cross-sectional view of the gas-insulated switchgear according to the third embodiment when the first circuit-breaking unit is in a closed state and the second circuit-breaking unit is in a circuit-breaking state. [Figure 8] 10 is a cross-sectional view of the gas-insulated switchgear according to the third embodiment when the first and second circuit-breaking units are in a closed state; [Figure 9] 10 is a cross-sectional view of the gas-insulated switchgear according to the third embodiment when the first circuit-breaking unit is in a circuit-breaking state and the second circuit-breaking unit is in a circuit-making state. [Figure 10] 10 is a cross-sectional view of the gas-insulated switchgear according to the third embodiment when the first and second circuit breakers are in a circuit breaker state. [Figure 11] 10 is a cross-sectional view of the gas-insulated switchgear according to the fourth embodiment when the first and second circuit breakers are in a circuit breaker state. [Figure 12] 10 is a cross-sectional view of the gas-insulated switchgear according to the fifth embodiment when the first and second circuit breakers are in a circuit breaker state. DETAILED DESCRIPTION OF THE INVENTION

[0012] Gas-insulated switchgear according to embodiments will be described in detail below with reference to the drawings.

[0013] Embodiment 1 1 is a diagram showing the configuration of a DC power transmission system using a gas-insulated switchgear according to embodiment 1. The DC power transmission system 500 includes a transmitting-side DC device 800, a core interrupter 700 constituting a core interrupter unit that interrupts a fault current, a gas-insulated switchgear 100, and a receiving-side DC device 600.

[0014] 2 is a cross-sectional view of the gas-insulated switchgear according to the first embodiment when the first and second circuit-breaking units are in a circuit-breaking state. The gas-insulated switchgear 100 includes a tank 1 filled with insulating gas, a first circuit-breaking unit 10 and a second circuit-breaking unit 20 installed in the tank 1, a power transmission unit 30 that transmits force generated by a drive unit (not shown) to the first circuit-breaking unit 10 and the second circuit-breaking unit 20, and a first insulating support member 40 that supports the first circuit-breaking unit 10 within the tank 1. The gas-insulated switchgear 100 also includes a second insulating support member 50 that supports the second circuit-breaking unit 20 within the tank 1, a first outer conductor 15 to which a DC current is input from the power-transmitting-side DC device 800, and a second outer conductor 16 that outputs a DC current to be transmitted to the power-receiving-side DC device 600. The tank 1 includes a cylindrical tank body 11 with both ends open, and lids 12 and 13 that close the openings at the ends of the tank body 11, and has an overall cylindrical shape with both ends closed. A current path connecting the first outer conductor 15 and the second outer conductor 16 is formed inside the tank 1. The first interrupter 10 and the second interrupter 20 are installed on the current path connecting the first outer conductor 15 and the second outer conductor 16. The second interrupter 20 is installed downstream of the first interrupter 10 in the current path connecting the first outer conductor 15 and the second outer conductor 16. Note that the second interrupter 20 may be installed upstream of the first interrupter 10 in the current path connecting the first outer conductor 15 and the second outer conductor 16.

[0015] The power transmission unit 30 includes a first link mechanism 31 that transmits a driving force input from a driving device (not shown) via a rod 14 to the first interrupting unit 10, a second link mechanism 32 that transmits a force generated by the driving device (not shown) to the second interrupting unit 20, the first link mechanism 31, the second link mechanism 32, and a movable-side shield 33 that houses a portion of each of the first interrupting unit 10 and the second interrupting unit 20. The movable-side shield 33 is formed of a conductor.

[0016] Circuit breakers are used for the first circuit breaker unit 10 and the second circuit breaker unit 20. The configurations of the first circuit breaker unit 10 and the second circuit breaker unit 20 described below are examples, and the first circuit breaker unit 10 and the second circuit breaker unit 20 may have configurations different from those illustrated.

[0017] The first interrupter 10 includes a first movable electrode 110 that moves in the axial direction of the tank 1 during opening and closing operations, a first fixed shield 120 to which the first outer conductor 15 is connected, and a first fixed electrode 130 installed on the first fixed shield 120. One end 110b of the first movable electrode 110 is rotatably connected to the other end 314b of the first connecting piece 314, as will be described later. The first fixed shield 120 is formed of a conductor.

[0018] The first interrupter 10 also includes a first nozzle 111 and a first puffer cylinder 112 fixed to the other end 110a of the first movable electrode 110, and a cylindrical first guide 113 installed within the movable shield 33. The first puffer cylinder 112 includes a bottom surface portion 112a and a cylindrical surface portion 112b, and an end closer to the axial center of the tank 1 is open. A first puffer piston 113a is provided at an end of the first guide 113 farther from the axial center of the tank 1. A first cylinder support portion 33a is provided on the movable shield 33 at a portion facing the first puffer piston 113a. The first cylinder support portion 33a supports the first puffer cylinder 112 by sandwiching it between itself and the first puffer piston 113a. The space surrounded by the first puffer cylinder 112, the first puffer piston 113a, and the first guide 113 forms a first puffer chamber 114. The first puffer chamber 114 is connected to the first nozzle 111. The first guide 113 is made of a conductor.

[0019] The first interrupter 10 also includes electric field mitigation shields 140 and 150 that surround the first movable electrode 110 and the first fixed electrode 130 in the radial direction of the tank 1.

[0020] The second interrupter 20 includes a second movable electrode 210 that moves in the axial direction of the tank 1 during opening and closing operations, a second fixed shield 220 to which the second outer conductor 16 is connected, and a second fixed electrode 230 installed on the second fixed shield 220. One end 210b of the second movable electrode 210 is rotatably connected to the other end 324b of the second connection piece 324, as will be described later. The second fixed shield 220 is made of a conductor.

[0021] The second interrupter 20 also includes a second nozzle 211 and a second puffer cylinder 212 fixed to the other end 210a of the second movable electrode 210, and a cylindrical second guide 213 installed within the movable shield 33. The second puffer cylinder 212 includes a bottom surface portion 212a and a cylindrical surface portion 212b, and an open end near the axial center of the tank 1. A second puffer piston 213a is provided at an end of the second guide 213 far from the axial center of the tank 1. A second cylinder support portion 33b is provided on the movable shield 33 at a portion facing the second puffer piston 213a. The second cylinder support portion 33b supports the second puffer cylinder 212 by sandwiching it between itself and the second puffer piston 213a. The space surrounded by the second puffer cylinder 212, the second puffer piston 213a, and the second guide 213 forms a second puffer chamber 214. The second puffer chamber 214 is connected to the second nozzle 211. The second guide 213 is made of a conductor.

[0022] The second blocking section 20 also includes electric field mitigation shields 240 and 250 that surround the second movable electrode 210 and the second fixed electrode 230 from the circumferential direction of the tank 1.

[0023] Furthermore, a resistor 70 is installed adjacent to the second interrupter 20. The resistor 70 is placed across the second fixed-side shield 220 and the movable-side shield 33. In this way, the resistor 70 is installed in parallel with the second interrupter 20 having a mechanical contact.

[0024] The first link mechanism 31 includes a first driving force input link 311 connected to one end 14a of the rod 14, which moves in a direction perpendicular to the axial direction of the tank 1 by force generated by a driving device (not shown), a first intermediate link 312 rotatably supported on the movable shield 33, and a first driving force output link 313 rotatably connected to the first intermediate link 312. The first intermediate link 312 is L-shaped and is supported on the movable shield 33 at a central bent portion. One end 311a of the first driving force input link 311 is connected to the one end 14a of the rod 14, and the other end 311b of the first driving force input link 311 is rotatably connected to one end 312a of the first intermediate link 312. The other end 312b of the first intermediate link 312 is rotatably connected to one end 313a of the first driving force output link 313. The other end 313b of the first driving force output link 313 is rotatably connected to one end 314a of the first connecting piece 314. The other end 314b of the first connecting piece 314 is rotatably connected to one end 110b of the first movable-side electrode 110. The first connecting piece 314 is made of an insulating material, and the first movable-side electrode 110 and the first driving force output link 313 are electrically insulated from each other.

[0025] The second link mechanism 32 includes a second driving force input link 321 connected to one end 14a of the rod 14, which moves in a direction perpendicular to the axial direction of the tank 1 by force generated by a driving device (not shown), a second intermediate link 322 rotatably supported on the movable shield 33, and a second driving force output link 323 rotatably connected to the second intermediate link 322. The second intermediate link 322 is L-shaped and is supported on the movable shield 33 at a central bent portion. One end 321a of the second driving force input link 321 is connected to one end 14a of the rod 14, and the other end 321b of the second driving force input link 321 is rotatably connected to one end 322a of the second intermediate link 322. The other end 322b of the second intermediate link 322 is rotatably connected to one end 323a of the second driving force output link 323. The other end 323b of the second driving force output link 323 is rotatably connected to one end 324a of the second connecting piece 324. The other end 324b of the second connecting piece 324 is rotatably connected to one end 210b of the second movable-side electrode 210. The second connecting piece 324 is formed of an insulating material, and the second movable-side electrode 210 and the second driving force output link 323 are electrically insulated from each other.

[0026] When a driving device (not shown) moves the rod 14 in a direction pushing it into the tank 1, the first driving force input link 311 moves together with the rod 14, and one end 312a of the first intermediate link 312 is pushed by the rod 14 and moves in a direction approaching the central axis of the tank 1. As a result, the other end 312b of the first intermediate link 312 rotates so that it moves away from the axial center of the tank 1. The first driving force output link 313 connected to the first intermediate link 312 moves in a direction away from the axial center of the tank 1 as the first intermediate link 312 rotates. As the first driving force output link 313 moves in a direction away from the axial center of the tank 1, the first connecting piece 314 and the first movable electrode 110 connected to the first driving force output link 313 also move in a direction away from the axial center of the tank 1. In this way, a driving device (not shown) moves the rod 14 in the direction of pushing it into the tank 1, and a closing operation is performed in the first interrupter 10 to bring the first movable side electrode 110 into contact with the first fixed side electrode 130.

[0027] When a driving device (not shown) moves the rod 14 in a direction pushing it into the tank 1, the second driving force input link 321 moves together with the rod 14, and one end 322a of the second intermediate link 322 is pushed by the rod 14 and moves in a direction approaching the central axis of the tank 1. As a result, the other end 322b of the second intermediate link 322 rotates so that it moves away from the axial center of the tank 1. The second driving force output link 323 connected to the second intermediate link 322 moves in a direction away from the axial center of the tank 1 as the second intermediate link 322 rotates. As the second driving force output link 323 moves in a direction away from the axial center of the tank 1, the second connecting piece 324 and the second movable electrode 210 connected to the second driving force output link 323 also move in a direction away from the axial center of the tank 1. In this way, a driving device (not shown) moves the rod 14 in the direction of pushing it into the tank 1, and a closing operation is performed in the second interrupter 20 to bring the second movable side electrode 210 into contact with the second fixed side electrode 230.

[0028] When a driving device (not shown) moves the rod 14 in a direction to pull it out of the tank 1, the first driving force input link 311 moves together with the rod 14, and one end 312a of the first intermediate link 312 is pulled by the rod 14 and moves in a direction away from the central axis of the tank 1. As a result, the other end 312b of the first intermediate link 312 rotates so that it approaches the axial center of the tank 1. The first driving force output link 313 connected to the first intermediate link 312 moves in a direction approaching the axial center of the tank 1 as the first intermediate link 312 rotates. As the first driving force output link 313 moves in a direction approaching the axial center of the tank 1, the first connecting piece 314 and the first movable electrode 110 connected to the first driving force output link 313 also move in a direction approaching the axial center of the tank 1. In this way, a driving device (not shown) moves the rod 14 in the direction of pulling it out of the tank 1, and an interrupting operation is performed in the first interrupter 10 to separate the first movable side electrode 110 from the first fixed side electrode 130.

[0029] During the breaking operation, the gap between the bottom surface 112a of the first puffer cylinder 112 and the first puffer piston 113a narrows, thereby reducing the volume of the first puffer chamber 114 and forcing the insulating gas in the first puffer chamber 114 out of the chamber. The insulating gas forced out of the first puffer chamber 114 is sprayed onto the first fixed-side electrode 130 through the first nozzle 111. As a result, the arc generated between the first movable-side electrode 110 and the first fixed-side electrode 130 during the breaking operation is cooled and extinguished by the insulating gas sprayed out from the first nozzle 111.

[0030] When a driving device (not shown) moves the rod 14 in a direction to pull it out of the tank 1, the second driving force input link 321 moves together with the rod 14, and one end 322a of the second intermediate link 322 is pulled by the rod 14 and moves in a direction away from the central axis of the tank 1. As a result, the other end 322b of the second intermediate link 322 rotates so that it approaches the axial center of the tank 1. The second driving force output link 323 connected to the second intermediate link 322 moves in a direction toward the axial center of the tank 1 as the second intermediate link 322 rotates. As the second driving force output link 323 moves in a direction toward the axial center of the tank 1, the second connecting piece 324 and the second movable-side electrode 210 connected to the second driving force output link 323 also move in a direction toward the axial center of the tank 1. In this way, a driving device (not shown) moves the rod 14 in the direction of pulling it out of the tank 1, and an interrupting operation is performed in the second interrupter 20 to separate the second movable side electrode 210 from the second fixed side electrode 230.

[0031] During the breaking operation, the gap between the bottom surface portion 212a of the second puffer cylinder 212 and the second puffer piston 213a narrows, thereby reducing the volume of the second puffer chamber 214 and forcing the insulating gas in the second puffer chamber 214 out of the chamber. The insulating gas forced out of the second puffer chamber 214 is sprayed onto the second fixed-side electrode 230 through the second nozzle 211. As a result, the arc generated between the second movable-side electrode 210 and the second fixed-side electrode 230 during the breaking operation is cooled and extinguished by the insulating gas sprayed from the second nozzle 211.

[0032] The closing operation of the gas-insulated switchgear 100 will be described. At the start of the closing operation, the first circuit breaker 10 and the second circuit breaker 20 are both in the circuit-breaking state, as shown in FIG. 2. When a driving device (not shown) applies a force to the rod 14 in a direction that pushes the rod 14 into the tank 1, the direction of the force is converted by the first link mechanism 31 and the second link mechanism 32, and the first movable-side electrode 110 and the second movable-side electrode 210 each move in a direction away from the center of the axial direction of the tank 1. Because the gap between the first movable-side electrode 110 and the first fixed-side electrode 130 is narrower than the gap between the second movable-side electrode 210 and the second fixed-side electrode 230, the first circuit breaker 10 enters the closed state first. FIG. 3 is a cross-sectional view of the gas-insulated switchgear according to the first embodiment when the first circuit breaker is in the closed state and the second circuit breaker is in the circuit-breaking state. In this state, the DC current input from the first outer conductor 15 flows to the second outer conductor 16 via the first fixed-side shield 120, the first fixed-side electrode 130, the first movable-side electrode 110, the first guide 113, the movable-side shield 33, the resistor 70, and the second fixed-side shield 220. That is, the current input from the first outer conductor 15 flows to the second outer conductor 16 via the resistor 70 installed in parallel with the second interrupter 20.

[0033] When the rod 14 is further pushed into the tank 1, the second movable-side electrode 210 comes into contact with the second fixed-side electrode 230, and both the first circuit breaker 10 and the second circuit breaker 20 are in the closed state. FIG. 4 is a cross-sectional view of the gas-insulated switchgear according to the first embodiment when the first circuit breaker and the second circuit breaker are in the closed state. In this state, a direct current input from the first outer conductor 15 flows to the second outer conductor 16 via the first fixed-side shield 120, the first fixed-side electrode 130, the first movable-side electrode 110, the first guide 113, the movable-side shield 33, the second guide 213, the second movable-side electrode 210, the second fixed-side electrode 230, and the second fixed-side shield 220. That is, the current input from the first outer conductor 15 flows to the second outer conductor 16 without passing through the resistor 70 installed in parallel with the second circuit breaker 20. In this way, in the closing operation, only the first circuit breaking unit 10 is first closed, and after a preset time has elapsed, the first circuit breaking unit 10 and the second circuit breaking unit 20 are closed. Note that the preset time here is a time set by the user, manufacturer, or other setter in accordance with the specifications of the DC power transmission system 500 and the characteristics of each device of the gas insulated switchgear 100, and is not limited to a specific time.

[0034] The interrupting operation of the gas-insulated switchgear 100 will now be described. At the start of the interrupting operation, the first interrupting unit 10 and the second interrupting unit 20 are both in the closed state, as shown in Fig. 4. When a driving device (not shown) applies a force to the rod 14 in a direction to pull the rod 14 out of the tank 1, the direction of the force is converted by the first link mechanism 31 and the second link mechanism 32, and the first movable-side electrode 110 and the second movable-side electrode 210 each move toward the center of the tank 1 in the axial direction. Because the gap between the first movable-side electrode 110 and the first fixed-side electrode 130 is narrower than the gap between the second movable-side electrode 210 and the second fixed-side electrode 230, the second interrupting unit 20 enters the interrupted state first, as shown in Fig. 3. In this state, the DC current input from the first outer conductor 15 flows to the second outer conductor 16 via the first fixed-side shield 120, the first fixed-side electrode 130, the first movable-side electrode 110, the movable-side shield 33, the resistor 70, and the second fixed-side shield 220. That is, the DC current input from the first outer conductor 15 flows to the second outer conductor 16 via the resistor 70 installed in parallel with the second interrupter 20. An arc generated between the second movable-side electrode 210 and the second fixed-side electrode 230 is extinguished by the insulating gas blown from the second nozzle 211.

[0035] When the rod 14 is further pulled out from the tank 1, the first movable-side electrode 110 separates from the first fixed-side electrode 130, and both the first interrupter 10 and the second interrupter 20 enter an interrupting state, as shown in Fig. 2. The arc generated between the first movable-side electrode 110 and the first fixed-side electrode 130 is extinguished by the insulating gas blown out from the first nozzle 111.

[0036] In the gas-insulated switchgear 100 according to the first embodiment, the second circuit breaker 20 functions as a bypass switch that switches between a current path in which a direct current flows via the resistor 70 and a current path in which a direct current flows without passing through the resistor 70. Therefore, the gas-insulated switchgear 100 according to the first embodiment starts, during a closing operation, the flow of current through a current path in which a direct current flows via the resistor 70, and after a preset time has elapsed since the start of the flow of current, can switch to a current path in which the direct current flows without passing through the resistor 70. Furthermore, during a breaking operation, the first circuit breaker 10 can quickly extinguish an arc that occurs between the first movable-side electrode 110 and the first fixed-side electrode 130, and can quickly extinguish an arc that occurs between the second movable-side electrode 210 and the second fixed-side electrode 230. Furthermore, in the gas-insulated switchgear 100 according to embodiment 1, the first circuit-breaking unit 10 that cuts off residual current when an accident occurs and the second circuit-breaking unit 20 that enables trial charging in a current path that includes the resistor 70 are installed in a common tank 1, thereby enabling the installation area of ​​the equipment that cuts off current during trial charging and when an accident occurs to be reduced.

[0037] In the above explanation, an example was given of a configuration in which the distance between the first movable side electrode 110 and the first fixed side electrode 130 is narrower than the distance between the second movable side electrode 210 and the second fixed side electrode 230, but it is also possible to configure the first link mechanism 31 and the second link mechanism 32 so that the movement distance of the first movable side electrode 110 and the movement distance of the second movable side electrode 210 are different.

[0038] Embodiment 2 5 is a cross-sectional view of the gas-insulated switchgear according to embodiment 2 when the first and second circuit-breaking units are in a circuit-breaking state. The gas-insulated switchgear 100 according to embodiment 2 differs from the gas-insulated switchgear 100 according to embodiment 1 in that the second circuit-breaking unit 20 has a configuration similar to that of a general disconnecting switch.

[0039] The closing operation and the breaking operation are similar to those of the gas-insulated switchgear 100 according to the first embodiment. The force of a drive device (not shown) pushing the rod 14 into the tank 1 or the force of a drive device pulling the rod 14 out of the tank 1 is converted into a force along the axial direction of the tank 1 by the first link mechanism 31 and the second link mechanism 32. Note that there may be one or more drive devices (not shown). As with the gas-insulated switchgear 100 according to the first embodiment, during the closing operation, only the first breaking unit 10 is first brought into the closed state, and after a preset time has elapsed, both the first breaking unit 10 and the second breaking unit 20 are brought into the closed state. Also, as with the gas-insulated switchgear 100 according to the first embodiment, during the breaking operation, only the second breaking unit 20 is brought into the broken state, and after a preset time has elapsed, both the first breaking unit 10 and the second breaking unit 20 are brought into the broken state.

[0040] Like the gas-insulated switchgear 100 according to the first embodiment, the gas-insulated switchgear 100 according to the second embodiment starts energization through a current path through which a DC current flows via the resistor 70 during a closing operation, and can switch to a current path through which the DC current does not flow via the resistor 70 after a preset time has elapsed since the start of energization. Furthermore, during an interrupting operation, an arc generated between the first movable-side electrode 110 and the first fixed-side electrode 130 in the first interrupting unit 10 can be quickly extinguished. Furthermore, in the gas-insulated switchgear 100 according to the second embodiment, the first interrupting unit 10 that interrupts residual current when an accident occurs and the second interrupting unit 20 that enables test charging through a current path including the resistor 70 are installed in a common tank 1, thereby making it possible to reduce the installation area of ​​devices that interrupt current during test charging and when an accident occurs. Furthermore, since disconnectors are generally smaller and lighter than circuit breakers, the gas-insulated switchgear 100 of embodiment 2, in which the second circuit-breaking section 20 has the same configuration as a general disconnector, can be made smaller and lighter than the gas-insulated switchgear 100 of embodiment 1, in which a circuit breaker is used for the second circuit-breaking section 20.

[0041] Embodiment 3 6 is a cross-sectional view of a gas-insulated switchgear according to embodiment 3 when the first and second circuit-breaking units are in a circuit-breaking state. In the gas-insulated switchgear 100 according to embodiment 3, the second movable-side electrode 210 has a contact portion 216 provided at the other end 210a facing the second fixed-side electrode 230, and the contact portion 216 is connected to a main body portion 217 including one end 210b of the second movable-side electrode 210 via a spring 215. A recess 24 is formed in the contact portion 216. A protrusion 25 is formed in the second fixed-side electrode 230.

[0042] When no external force is applied to the spring 215, the distance between the second movable-side electrode 210 and the second fixed-side electrode 230 is wider than the distance between the first movable-side electrode 110 and the first fixed-side electrode .

[0043] The closing operation of the gas-insulated switchgear 100 will be described. At the start of the closing operation, both the first circuit breaker 10 and the second circuit breaker 20 are in the circuit breaker state. When a driving device (not shown) applies a force to the rod 14 in a direction that pushes the rod 14 into the tank 1, the direction of the force is converted by the first link mechanism 31 and the second link mechanism 32, and the first movable-side electrode 110 and the second movable-side electrode 210 each move in a direction away from the axial center of the tank 1. Because the gap between the first movable-side electrode 110 and the first fixed-side electrode 130 is narrower than the gap between the second movable-side electrode 210 and the second fixed-side electrode 230 when no external force is applied to the spring 215, the first circuit breaker 10 enters the closed state first. FIG. 7 is a cross-sectional view of the gas-insulated switchgear according to the third embodiment when the first circuit breaker is in the closed state and the second circuit breaker is in the circuit breaker state. In this state, the DC current input from the first outer conductor 15 flows to the second outer conductor 16 via the first fixed-side shield 120, the first fixed-side electrode 130, the first movable-side electrode 110, the movable-side shield 33, the resistor 70, and the second fixed-side shield 220. That is, the current input from the first outer conductor 15 flows to the second outer conductor 16 via the resistor 70 installed in parallel with the second interrupter 20.

[0044] When the rod 14 is further pushed into the tank 1, the second movable-side electrode 210 comes into contact with the second fixed-side electrode 230, and both the first circuit breaker 10 and the second circuit breaker 20 are in the closed state. FIG. 8 is a cross-sectional view of the gas-insulated switchgear according to the third embodiment when the first circuit breaker and the second circuit breaker are in the closed state. In this state, a direct current input from the first outer conductor 15 flows to the second outer conductor 16 via the first fixed-side shield 120, the first fixed-side electrode 130, the first movable-side electrode 110, the movable-side shield 33, the second movable-side electrode 210, the second fixed-side electrode 230, and the second fixed-side shield 220. That is, the current input from the first outer conductor 15 flows to the second outer conductor 16 without passing through the resistor 70 installed in parallel with the second circuit breaker 20. When the second circuit breaker 20 is in the closed state, the recess 24 of the contact portion 216 and the protrusion 25 of the second fixed-side electrode 230 are engaged. When the second blocking unit 20 is in the closed state, the spring 215 is compressed.

[0045] The interrupting operation of the gas-insulated switchgear 100 will now be described. At the start of the interrupting operation, the first interrupting unit 10 and the second interrupting unit 20 are both in the closed state, as shown in FIG. 8 . When a driving device (not shown) applies a force to the rod 14 in a direction to pull the rod 14 out of the tank 1, the direction of the force is converted by the first link mechanism 31 and the second link mechanism 32, and the main body portions 217 of the first movable-side electrode 110 and the second movable-side electrode 210 each move toward the center of the tank 1 in the axial direction. FIG. 9 is a cross-sectional view of the gas-insulated switchgear according to the third embodiment, when the first interrupting unit is in the interrupted state and the second interrupting unit is in the closed state. Because the recessed portion 24 of the contact portion 216 and the protruding portion 25 of the second fixed-side electrode 230 are engaged, the spring 215 is extended. Therefore, when the first interrupting unit 10 transitions to the interrupted state, the second interrupting unit 20 maintains the closed state, and the first interrupting unit 10 transitions to the interrupted state first. The arc generated between the first movable electrode 110 and the first fixed electrode 130 is extinguished by the insulating gas blown out from the first nozzle 111 .

[0046] 10 is a cross-sectional view of the gas-insulated switchgear according to embodiment 3 when the first and second circuit breakers are in a circuit breaker state. When the rod 14 is further pulled out from the tank 1 and the elastic force of the spring 215 becomes stronger than the engagement force between the recessed portion 24 and the protruding portion 25, the contact portion 216 disengages from the second fixed-side electrode 230, and the contact portion 216 of the second movable-side electrode 210 and the second fixed-side electrode 230 are separated from each other. As a result, both the first circuit breaker 10 and the second circuit breaker 20 are in a circuit breaker state.

[0047] Note that a damping mechanism may be provided in the second movable-side electrode 210 to suppress expansion and contraction of the spring 215 caused by disengagement between the recessed portion 24 and the protruding portion 25. By providing a damping mechanism in the second movable-side electrode 210, it is possible to suppress re-ignition of an arc between the second movable-side electrode 210 and the second fixed-side electrode 230 caused by expansion and contraction of the spring 215.

[0048] In the gas-insulated switchgear 100 according to the third embodiment, the first circuit breaking unit 10, which uses a circuit breaker, transitions to the circuit breaking state first during the circuit breaking operation, and therefore, at the timing when the second circuit breaking unit 20, which is configured similarly to a general disconnecting switch, transitions to the circuit breaking state, no current flows through the second circuit breaking unit 20. Therefore, during the circuit breaking operation of the second circuit breaking unit 20, no arc is generated between the second movable-side electrode 210 and the second fixed-side electrode 230. This makes it possible to suppress wear of the second movable-side electrode 210 and the second fixed-side electrode 230 during current interruption.

[0049] Embodiment 4 11 is a cross-sectional view of the gas-insulated switchgear according to embodiment 4 when the first and second circuit-breaking units are in a circuit-breaking state. In the gas-insulated switchgear 100 according to embodiment 4, the second fixed-side electrode 230 has a contact portion 236 facing the second movable-side electrode 210, which is connected to the second fixed-side shield 220 via a spring 235.

[0050] When no external force is applied to the spring 235, the distance between the second movable-side electrode 210 and the second fixed-side electrode 230 is wider than the distance between the first movable-side electrode 110 and the first fixed-side electrode .

[0051] The closing operation of the gas-insulated switchgear 100 will now be described. At the start of the closing operation, both the first circuit breaker 10 and the second circuit breaker 20 are in the circuit breaker state. When a driving device (not shown) applies a force to the rod 14 in a direction that pushes the rod 14 into the tank 1, the direction of the force is converted by the first link mechanism 31 and the second link mechanism 32, and the first movable-side electrode 110 and the second movable-side electrode 210 each move in a direction away from the center of the axial direction of the tank 1. Because the gap between the first movable-side electrode 110 and the first fixed-side electrode 130 is narrower than the gap between the second movable-side electrode 210 and the second fixed-side electrode 230 when no external force is applied to the spring 235, the first circuit breaker 10 enters the closed state first. In this state, the DC current input from the first outer conductor 15 flows to the second outer conductor 16 via the first fixed-side shield 120, the first fixed-side electrode 130, the first movable-side electrode 110, the movable-side shield 33, the resistor 70, and the second fixed-side shield 220. That is, the current input from the first outer conductor 15 flows to the second outer conductor 16 via the resistor 70 installed in parallel with the second interrupter 20.

[0052] When the rod 14 is further pushed into the tank 1, the second movable-side electrode 210 comes into contact with the second fixed-side electrode 230, and both the first circuit breaker 10 and the second circuit breaker 20 are in the closed state. In this state, a direct current input from the first outer conductor 15 flows to the second outer conductor 16 via the first fixed-side shield 120, the first fixed-side electrode 130, the first movable-side electrode 110, the movable-side shield 33, the second movable-side electrode 210, the second fixed-side electrode 230, and the second fixed-side shield 220. In other words, the current input from the first outer conductor 15 flows to the second outer conductor 16 without passing through the resistor 70 installed in parallel with the second circuit breaker 20. When the second circuit breaker 20 is in the closed state, the recess 24 of the second movable-side electrode 210 and the protrusion 25 of the contact portion 236 are engaged. When the second circuit breaker 20 is in the closed state, the spring 235 is compressed.

[0053] The interrupting operation of the gas-insulated switchgear 100 will now be described. At the start of the interrupting operation, both the first interrupting unit 10 and the second interrupting unit 20 are in the closed state. When a driving device (not shown) applies a force to the rod 14 in a direction to pull the rod 14 out of the tank 1, the direction of the force is converted by the first link mechanism 31 and the second link mechanism 32, and the first movable-side electrode 110 and the second movable-side electrode 210 each move toward the center of the tank 1 in the axial direction. Because the recess 24 of the second movable-side electrode 210 and the protrusion 25 of the contact portion 236 are engaged, the spring 235 expands. When the first interrupting unit 10 transitions to the interrupted state, the second interrupting unit 20 remains in the closed state, and the first interrupting unit 10 transitions to the interrupted state first. An arc generated between the first movable-side electrode 110 and the first fixed-side electrode 130 is extinguished by insulating gas blown from the first nozzle 111.

[0054] When the rod 14 is further pulled out from the tank 1 and the elastic force of the spring 235 becomes stronger than the engagement force between the recessed portion 24 and the protruding portion 25, the second movable-side electrode 210 comes off the contactor portion 236, and the second movable-side electrode 210 and the second fixed-side electrode 230 are separated from each other. As a result, both the first circuit breaker 10 and the second circuit breaker 20 are in the circuit breaking state.

[0055] It is also possible to provide a damping mechanism in the second fixed-side electrode 230 to suppress expansion and contraction of the spring 235 caused by disengagement between the recessed portion 24 and the protruding portion 25. By providing a damping mechanism in the second fixed-side electrode 230, it is possible to suppress the re-ignition of an arc between the second movable-side electrode 210 and the second fixed-side electrode 230 caused by expansion and contraction of the spring 235.

[0056] In the gas-insulated switchgear 100 according to the fourth embodiment, the first circuit breaking unit 10, which uses a circuit breaker, transitions to the circuit breaking state first during the circuit breaking operation, and therefore, at the timing when the second circuit breaking unit 20, which is configured similarly to a general disconnecting switch, transitions to the circuit breaking state, no current flows through the second circuit breaking unit 20. Therefore, during the circuit breaking operation of the second circuit breaking unit 20, no arc is generated between the second movable-side electrode 210 and the second fixed-side electrode 230. This makes it possible to suppress wear of the second movable-side electrode 210 and the second fixed-side electrode 230 during current interruption.

[0057] Embodiment 5. 12 is a cross-sectional view of a gas-insulated switchgear according to embodiment 5 when the first and second circuit breakers are in a circuit breaker state. In the gas-insulated switchgear 100 according to embodiment 5, driving forces are input separately to the first link mechanism 31 and the second link mechanism 32. One end 311a of a first driving force input link 311 of the first link mechanism 31 is rotatably connected to one end 141a of a first rod 141. One end 321a of a second driving force input link 321 of the second link mechanism 32 is rotatably connected to one end 142a of a second rod 142. A first driving force is input to the first link mechanism 31 via the first rod 141. A second driving force is input to the second link mechanism 32 via the second rod 142. The rest is the same as that of the gas-insulated switchgear 100 according to embodiment 1.

[0058] In the gas-insulated switchgear 100 according to the fifth embodiment, the distance between the first movable-side electrode 110 and the first fixed-side electrode 130 and the distance between the second movable-side electrode 210 and the second fixed-side electrode 230 are set arbitrarily.

[0059] In the closing operation and the breaking operation, the first driving force and the second driving force are input to the first link mechanism 31 and the second link mechanism 32 at different times. That is, in the closing operation, the first driving force is input to the first link mechanism 31 first, and after a preset time has elapsed, the second driving force is input to the second link mechanism 32. As a result, in the closing operation, only the first breaking unit 10 is first brought into the closed state, and after a preset time has elapsed, both the first breaking unit 10 and the second breaking unit 20 are brought into the closed state. In the breaking operation, the second driving force is input to the second link mechanism 32 first, and after a preset time has elapsed, the first driving force is input to the first link mechanism 31. As a result, in the breaking operation, only the second breaking unit 20 is first brought into the broken state, and after a preset time has elapsed, both the first breaking unit 10 and the second breaking unit 20 are brought into the broken state.

[0060] In the gas-insulated switchgear 100 according to the fifth embodiment, similarly to the gas-insulated switchgear 100 according to the first embodiment, the second circuit breaker 20 functions as a bypass switch that switches between a current path in which a DC current flows via the resistor 70 and a current path in which a DC current flows without passing through the resistor 70. Therefore, the gas-insulated switchgear 100 according to the fifth embodiment starts current flow through the current path in which a DC current flows via the resistor 70 during a closing operation, and can switch to a current path in which a DC current flows without passing through the resistor 70 after a preset time has elapsed since the start of current flow. Furthermore, during a breaking operation, an arc generated between the first movable-side electrode 110 and the first fixed-side electrode 130 in the first circuit breaker 10 can be quickly extinguished, and an arc generated between the second movable-side electrode 210 and the second fixed-side electrode 230 in the second circuit breaker 20 can be quickly extinguished. Furthermore, in the gas-insulated switchgear 100 according to embodiment 5, the first circuit-breaking unit 10 that cuts off residual current when an accident occurs and the second circuit-breaking unit 20 that enables trial charging in a current path that includes the resistor 70 are installed in a common tank 1, thereby enabling the installation area of ​​the equipment that cuts off current during trial charging and when an accident occurs to be reduced.

[0061] Here, we have described a gas-insulated switchgear 100 that is similar to embodiment 1 except that driving forces are input separately to the first link mechanism 31 and the second link mechanism 32. However, it is also possible to implement a gas-insulated switchgear 100 that is similar to embodiment 2, embodiment 3, or embodiment 4 except that driving forces are input separately to the first link mechanism 31 and the second link mechanism 32.

[0062] The configurations shown in the above embodiments are merely examples of the content, and may be combined with other known technologies, or parts of the configurations may be omitted or modified without departing from the spirit of the invention. [Explanation of symbols]

[0063] 1 tank, 10 first interrupting part, 11 tank body, 12, 13 lid part, 14 rod, 14a, 110b, 141a, 142a, 210b, 311a, 312a, 313a, 314a, 321a, 322a, 323a, 324a one end part, 15 first outer conductor, 16 second outer conductor, 20 second interrupting part, 24 recess, 25 protrusion, 30 power transmission part, 31 first link mechanism, 32 second link mechanism, 33 moving side shield, 33a first cylinder support part, 33b second cylinder support part, 40 first insulating support member, 50 second insulating support member, 70 resistor, 100 gas insulated switchgear, 110 First movable-side electrode, 110a, 210a, 311b, 312b, 313b, 314b, 321b, 322b, 323b, 324b Other end, 111 First nozzle, 112 First puffer cylinder, 112a Bottom surface portion, 112b Cylindrical surface portion, 113 First guide, 113a First puffer piston, 114 First puffer chamber, 120 First fixed-side shield, 130 First fixed-side electrode, 140, 150, 240, 250 Electric field relaxation shield, 141 First rod, 142 Second rod, 210 Second movable-side electrode, 211 Second nozzle, 212 Second puffer cylinder, 212a Bottom surface portion, 212b Cylindrical surface portion, 213 Second guide, 213a Second puffer piston, 214 Second puffer chamber, 215, 235 springs, 216, 236 contact portions, 217 main body portion, 220 second fixed side shield, 230 second fixed side electrode, 311 first driving force input link, 312 first intermediate link, 313 first driving force output link, 314 first connecting piece, 321 second driving force input link, 322 second intermediate link, 323 second driving force output link, 324 second connecting piece, 500 DC transmission system, 600 receiving side DC equipment, 700 core breaking device, 800 transmitting side DC equipment.

Claims

1. a tank filled with insulating gas and having a current path therein connecting a first outer conductor to which a direct current is input and a second outer conductor to which the direct current is output; a first interrupting unit and a second interrupting unit installed on the current path within the tank; a resistor disposed in parallel with the second interrupter, The first interrupting unit is a circuit breaker, and the second interrupting unit is a disconnecting switch, a gas-insulated switchgear characterized in that, in a closing operation, only the first circuit breaking unit is first brought into a closed state, and after a preset time has elapsed, the first circuit breaking unit and the second circuit breaking unit are brought into a closed state.

2. a tank filled with insulating gas and having a current path therein connecting a first outer conductor to which a direct current is input and a second outer conductor to which the direct current is output; a first interrupting unit and a second interrupting unit installed on the current path within the tank; a resistor disposed in parallel with the second interrupter, the first interrupter includes a first fixed electrode fixed in the tank and a first movable electrode that contacts the first fixed electrode in a closing operation and moves away from the first fixed electrode in a breaking operation, the second interrupter includes a second fixed electrode fixed within the tank and a second movable electrode that contacts the second fixed electrode in the closing operation and moves away from the second fixed electrode in the breaking operation, In the closing operation, only the first breaking unit is first put into a closing state, and after a preset time has elapsed, the first breaking unit and the second breaking unit are put into a closing state, the second movable-side electrode has a contact portion provided at one end thereof facing the second fixed-side electrode, the contact portion being connected via a spring to a main body portion including the other end of the second movable-side electrode; the contact portion is engaged with the second fixed electrode in a closed state, a gas-insulated switchgear characterized in that, during the breaking operation, the spring is extended, so that the second breaking unit maintains the closed state when the first breaking unit transitions to the broken state.

3. a tank filled with insulating gas and having a current path therein connecting a first outer conductor to which a direct current is input and a second outer conductor to which the direct current is output; a first interrupting unit and a second interrupting unit installed on the current path within the tank; a resistor disposed in parallel with the second interrupter, the first interrupter includes a first fixed electrode fixed in the tank and a first movable electrode that contacts the first fixed electrode in a closing operation and moves away from the first fixed electrode in a breaking operation, the second interrupter includes a second fixed electrode fixed within the tank and a second movable electrode that contacts the second fixed electrode in the closing operation and moves away from the second fixed electrode in the breaking operation, In the closing operation, only the first breaking unit is first put into a closing state, and after a preset time has elapsed, the first breaking unit and the second breaking unit are put into a closing state, a contact portion provided at one end of the second fixed electrode facing the second movable electrode is connected via a spring to a fixed shield to which the second outer conductor is connected; the contact portion is engaged with the second movable-side electrode in a closed state, a gas-insulated switchgear characterized in that, during the breaking operation, the spring is extended, so that the second breaking unit maintains the closed state when the first breaking unit transitions to the broken state.

4. a first link mechanism that transmits a driving force to the first interrupting unit, and a second link mechanism that transmits the driving force to the second interrupting unit, the first movable electrode is moved by the driving force transmitted via the first link mechanism, and comes into contact with the first fixed electrode in the closing operation and separates from the first fixed electrode in the breaking operation; the second movable electrode is moved by the driving force transmitted via the second link mechanism, and comes into contact with the second fixed electrode in the closing operation and separates from the second fixed electrode in the breaking operation; 4. The gas-insulated switchgear according to claim 2, wherein a distance between the first movable electrode and the first fixed electrode is narrower than a distance between the second movable electrode and the second fixed electrode.

5. a first link mechanism that transmits a first driving force to the first interrupter, and a second link mechanism that transmits a second driving force to the second interrupter; the first movable electrode is moved by the first driving force transmitted via the first link mechanism, and comes into contact with the first fixed electrode in the closing operation and separates from the first fixed electrode in the breaking operation; the second movable electrode is moved by the second driving force transmitted via the second link mechanism, and comes into contact with the second fixed electrode in the closing operation and separates from the second fixed electrode in the breaking operation; In the closing operation, the second driving force is input to the second link mechanism after a preset time has elapsed since the first driving force was input to the first link mechanism, 4. The gas-insulated switchgear according to claim 2, wherein, in the breaking operation, the first driving force is input to the first link mechanism after a predetermined time has elapsed since the second driving force was input to the second link mechanism.

6. 4. The gas-insulated switchgear according to claim 2, wherein the first circuit-breaking unit is a circuit breaker, and the second circuit-breaking unit is a disconnecting switch.

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