JP2012039872A - Switchgear - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize downsizing of switchgear that uses aerial insulation.SOLUTION: Switchgear of the present invention includes: a vacuum valve that includes a fixed electrode and a movable electrode and has a vacuum inside; and an aerial grounding disconnection part that has a movable electrode for the grounding disconnection part, a bus-side fixed electrode positioned on a bus side, an intermediate fixed electrode electrically coupled to an electrode in the vacuum valve, and a grounding-side fixed electrode having a grounding potential. The movable electrode for the grounding disconnection part can come in contact with the bus-side fixed electrode, the intermediate fixed electrode, and the grounding-side fixed electrode. The movable electrode for the grounding disconnection part is linearly moved between three positions: a close position, a disconnecting position, and a grounding position.

Description

The present invention relates to Suitchigi ya comprise aerial earthing and disconnecting switch which performs the air-insulated grounding-disconnector.

  An example of a conventional switchgear will be described using the configuration of a cubicle type gas insulated switchgear described in Patent Document 1. The switch gear is provided with a three-position ground disconnection portion having a contactor as a rotor in a metal container, and a vacuum valve. One end of the three-position ground disconnection portion is connected to a vacuum valve, and the other end is connected to a high voltage cable via a bushing bus and a bushing. The other end of the vacuum valve that is not connected to the three-position ground disconnection is connected to the bus via the bushing bus and the bushing, and is electrically connected to the adjacent switchboard.

  In this configuration, by inserting the rotor of the three-position ground disconnection portion to the bus bar side and further turning on the vacuum valve, the bus bar and the cable are electrically connected, and power is supplied from the bus bar to the cable.

JP-A-6-12948

However, in the conventional cubicle type gas-insulated switchgear, the vacuum valve and the three-position ground disconnection are provided inside the metal container filled with SF ₆ gas. High epoxy resin bushings are required. In addition, an O-ring or an O-ring groove for maintaining airtightness between the bushing and the metal container is required, and the number of parts is large and the configuration is complicated. Furthermore, since SF ₆ gas having a high global warming potential is used as an insulating medium, there is a problem that environmental compatibility is low.

In addition, when air insulation is adopted, SF ₆ gas has good insulation performance, so even a method of switching with a rotor is unlikely to cause an increase in size, but the air insulation performance is lower than that of SF ₆ gas. In this case, if the method of switching with a rotor is adopted, the size of the disconnection portion becomes large, and there is a problem that the entire apparatus becomes large.

The present invention has been made based on the above-described matters, and an object of the present invention is to provide a switchgear that can be downsized even if air insulation is employed .

The switchgear according to the present invention includes a fixed electrode and a movable electrode, and a vacuum valve having a vacuum inside, a ground disconnection portion movable electrode, a busbar side fixed electrode disposed on the busbar side, and a vacuum valve in the vacuum valve. an intermediate fixed electrode electrically connected to the electrode, and an aerial earthing and disconnecting switch and a ground side fixed electrode is the ground potential, the earthing and disconnecting switch movable electrode the bus side fixed electrode, the intermediate fixed electrode The grounding disconnecting portion movable electrode is linearly displaced to three positions of a closed position, a disconnecting position, and a grounding position.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the switchgear which does not enlarge even if it uses an air ground disconnection part .

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front sectional view showing a first embodiment of a switchgear of the present invention and is a diagram showing a voltage / current application state. It is a single phase connection diagram for demonstrating operation | movement of the switchgear of this invention shown in FIG. FIG. 2 is a front sectional view for explaining the operation of the switchgear of the present invention shown in FIG. FIG. 2 is a front sectional view for explaining an operation in a disconnected state of the switchgear of the present invention shown in FIG. 1. FIG. 2 is a front sectional view for explaining the operation of the switchgear of the present invention shown in FIG. FIG. 2 is a front sectional view for explaining the operation of the switchgear of the present invention shown in FIG. 1 in a grounded state. FIG. 2 is a front sectional view for explaining a bus side conductor arrangement of the switchgear of the present invention shown in FIG. 1. It is a top view of the switching apparatus for 3 phase 3 circuits comprised with the switchgear of this invention shown in FIG. It is a front view of the switching apparatus for three-phase three-circuits comprised with the switchgear of this invention shown in FIG. The front sectional view of a 2nd embodiment of the switchgear of the present invention. The top view of 2nd Embodiment of the switchgear of this invention. It is a single phase connection diagram for demonstrating operation | movement of 2nd Embodiment of the switchgear of this invention. FIG. 11 is a front sectional view for explaining the operation of the switchgear of the present invention shown in FIG. FIG. 11 is a front sectional view for explaining an operation of the switchgear of the present invention shown in FIG. 10 in a disconnected state. FIG. 11 is a front sectional view for explaining an operation of the switchgear of the present invention shown in FIG. 10 in a grounded state. The side sectional view of a 3rd embodiment of the switchgear of the present invention. The top view of 3rd Embodiment of the switchgear of this invention. The front view of 3rd Embodiment of the switchgear of this invention. The front sectional view of the 4th embodiment of the switchgear of the present invention. The perspective view of the switching apparatus for 3 phase 3 circuits comprised with the switchgear of this invention shown in FIG. FIG. 10 is a front cross-sectional view of the fifth embodiment of the switchgear of the present invention in a closing state. The front sectional view of the ground state of the 5th embodiment of the switchgear of the present invention.

A first embodiment of a switchgear according to the present invention will be described below with reference to FIGS.
The switchgear switch unit according to the present embodiment includes a vacuum valve 1, a ground disconnection unit 10, a bus bushing 40, which are integrally cast with a solid insulator 30 such as epoxy, in a grounded metal container 31. The cable bushing 42 is provided.

The vacuum valve 1 includes a fixed side electrode 6A, a movable side electrode 6B, and a fixed side in a vacuum container composed of a fixed side ceramic insulating cylinder 2A, a movable side ceramic insulating cylinder 2B, a fixed side end plate 3A and a movable side end plate 3B. A fixed side holder 7A connected to the side electrode 6A, a movable side holder 7B connected to the movable side electrode 6B, and an arc shield 5 for protecting the ceramic insulating cylinder from an arc are provided, and the fixed side holder 7A is a cable. The bushing central conductor 43 is connected to supply power to the load side. Moreover, the bellows 9 for implement | achieving the movement of the movable side holder 7B is arrange | positioned at the movable side. The vacuum valve 1 is turned off by allowing the movable side electrode 6B and the movable side holder 7B to move in the axial direction while maintaining the internal vacuum by the bellows 9 connected to the movable side end plate 3B and the movable side holder 7B. Is switched. In addition, a bellows shield 8 is provided in the vicinity of the connection portion between the bellows 9 and the movable electrode 6B to protect the bellows 9 from an arc or the like during opening and closing, and at the same time, the concentration of the electric field at the end of the bellows is reduced. You can also. A fixed-side electric field relaxation shield 4A is arranged around the fixed-side ceramic insulating cylinder 2A to alleviate electric field concentration at the connection portion with the fixed-side end plate 3A. A movable- side end is arranged around the movable-side ceramic insulating cylinder 2B. It is placed at the movable side electric field relaxation shield 4 B to reduce the electric field concentration at the connecting portion between the plate 3 B.

  The ground disconnection portion 10 is located between the bushing-side fixed electrode 11 connected to the bus bar via the bus-bushing central conductor 41, the ground-side fixed electrode 14 having the ground potential, and a flexible conductor. 15 is provided with an intermediate fixed electrode 13 that is electrically connected to the movable side holder 7B on the vacuum valve side via 15 and is internally insulated in the air. These fixed electrodes are arranged in a straight line, and the inner diameters are all equal. The ground disconnection portion movable electrode 12 moves linearly in the ground disconnection portion 10 with respect to each of these fixed electrodes, thereby enabling switching to three positions of closed, disconnection, and ground. The ground disconnection section movable electrode 12 is connected to a ground disconnection section operating rod 21 connected to an operation mechanism (not shown), and can be moved. In the ground disconnection section movable electrode 12, the contact portion with each of the fixed contacts is constituted by the spring contact 16, thereby preventing the ground disconnection section movable electrode 12 from moving and reliably realizing contact by an elastic force. I can do it.

  The switchgear switch unit of FIG. 1 includes a vacuum valve 1 having at least a pair of contacts that can be contacted and separated, a ground disconnecting portion movable electrode 12 that is provided in the atmosphere and is linearly displaced in three positions, and a movable The bushing side fixed electrode 11 and the intermediate fixed electrode 13 electrically connected through the movable electrode in the closed position, and the ground side fixed electrode in which the movable electrode is connected to the intermediate fixed electrode 13 through the movable electrode in the ground position 14, a cable bushing 42 connected to the fixed side of the vacuum valve 1, a bus bushing 40 connected to the bushing-side fixed electrode 11 of the ground disconnection part 10, and the ground disconnection part 10. A flexible conductor 15 that connects the intermediate fixed electrode 13 and the movable side of the vacuum valve 1, and a vacuum bar that is mechanically connected to the movable side electrode 7B of the vacuum valve. The operation rod 20 for the bushing and the operation rod 21 for the grounding disconnection portion mechanically connected to the movable electrode 12 of the grounding disconnection portion, the vacuum valve 1, the bushing side fixed electrode 11 for the grounding disconnection portion, and the bushing 40 for the busbar. And the cable bushing 42 were integrally cast with the solid insulator 30.

  The bus bushing 40 is configured by covering the periphery of the bus bushing center conductor 41 with the solid insulator 30, and the cable bushing 42 is configured by covering the periphery of the cable bushing center conductor 43 with the solid insulator 30. Is done.

  The operation of the first embodiment of the switchgear of the present invention configured as described above will be described with reference to FIGS.

  FIG. 2 is a single-phase connection diagram for explaining the operation of the first embodiment of the switchgear of the present invention, in which three switch units having the configuration of FIG. 1 are connected by a common bus 50. . By connecting the common bus 50 to the bus bushing 40, a three-circuit switching switch is configured. 2, the ground disconnection portion bushing side fixed electrode 11 of FIG. 1 is connected to the ground disconnection portion fixed contacts 51A, 51B, 51C, and the ground disconnection portion movable electrode 12 of FIG. 1 is connected to the ground disconnection portion movable contacts 53A, 53B, 53C. The ground disconnection portion ground side fixed electrode 14 of FIG. 1 is connected to the ground disconnection portion ground contacts 52A, 52B, 52C, and the fixed side electrode 6A of the vacuum valve 1 of FIG. 1 is connected to the current switching portion fixed contacts 54A, 54B, 54C. The electrode 6B corresponds to the current switching unit movable contacts 55A, 55B, and 55C, and the cable bushings 42 are connected to the cable heads 56A, 56B, and 56C. After switching the ground disconnection section movable contacts 53A, 53B, 53C to the closed position, the common bus 50 and the cable heads 56A, 56B, 56C are connected by turning the current switching section movable contacts 55A, 55B, 55C into the closed position. Each is electrically connected, and for example, power on the bus side can be supplied to the load side. At the time of disconnection, the current is first interrupted by the current opening / closing portion movable contacts 55A, 55B, 55C, and thereafter the ground disconnection portion movable contacts 53A, 53B, 53C are switched to the disconnect position. The grounding can be achieved by switching the ground disconnection part movable contacts 53A, 53B, 53C to the grounding position from the disconnection and setting the current switching part movable contact to the closing position.

  FIG. 3 shows a cut-off state. In the input state shown in FIG. 1, a load current is passed from the bus bushing 40 to the cable bushing 42 via the ground disconnection portion 10 and the vacuum valve 1. In this state, when a short circuit occurs on the load side connected to the cable bushing and a large accident current flows, the accident current is interrupted by shutting off the vacuum valve 1 as shown in FIG.

  FIG. 4 shows a disconnected state. Both the ground disconnection part movable electrode 12 and the bushing side fixed electrode 11, the ground disconnection part movable electrode 12 and the ground side fixed electrode 14 are not conductive, and the gap between the ground disconnection part movable electrode 12 and the bushing side fixed electrode 11 is large. Thus, the ground disconnection section movable electrode 12 is driven downward to the position of the drawing sheet until the gap between the ground disconnection section movable electrode 12 and the ground side fixed electrode 14 becomes small.

  At this time, since the bus bushing 40 and the cable bushing 42 are disconnected at two points, that is, the vacuum valve 1 and the ground disconnection portion 10, the reliability is high. In addition, by designing the withstand voltage between the ground disconnection part movable electrode 12 and the ground side fixed electrode 14 to be lower than the withstand voltage between the fixed side electrode 6A and the movable side electrode 6B of the vacuum valve 1, the ground fault is given priority. A highly reliable structure can be obtained.

  FIG. 5 shows the state of ground contact. As shown in the figure, the ground disconnection section movable electrode 12, the flexible conductor 15, and the movable conductor 12 are driven by driving the ground disconnection section movable electrode 12 down to the position where the ground disconnection section movable electrode 12 and the ground side fixed electrode 14 are in contact with each other. The side electrode 6B becomes a ground potential, and a potential difference from the load side is applied between the electrodes in the vacuum valve 1.

  FIG. 6 shows a grounding state. When the vacuum valve 1 is further turned on from the state shown in FIG. 5, the cable bushing 42 passes through the vacuum valve 1, the flexible conductor 15, the intermediate fixed electrode 13, the ground disconnection portion movable electrode 12, and the ground side fixed electrode 14. To be grounded. At this time, even if the cable bushing 42 is in the power-applied state, the final closing operation is performed by the vacuum valve 1, so that no short-circuit current input capacity is required for the ground disconnection unit 10.

  In order to return from the grounding state to the closing state again, the inside of the vacuum valve 1 is shut off, and then the grounding disconnecting portion movable electrode 12 is moved so that the spring contact 16 contacts the bushing side fixed electrode 11, and then the vacuum valve 1, the movable side electrode 6B is inserted.

  As described above, in the present embodiment, the insulation is configured with an insulation best mix in which air, vacuum, and solid insulation are optimally combined, and no fluorocarbon is used. Therefore, downsizing can be realized while reducing environmental burden. . In addition, by providing the metal container with solid insulation and insulation with the atmosphere, there is no need to provide a sealing member, the number of parts can be reduced, and the configuration is simplified. Furthermore, each fixed electrode is arranged in a straight line, and by using the ground disconnection part 10 that operates in a straight line, although it becomes a little longer in the height direction where there is a relatively large space for installing the switchgear, This is practical in that the area can be prevented from increasing. In addition, since the earthing disconnection part 10 is not provided with a closing function and the short-circuit current charging capacity is borne by the vacuum valve 1, it is possible to prevent the apparatus from being enlarged even if the grounding disconnection part 10 is used. Moreover, it is configured to be slidable by using a spring contact, and can be switched between closing, disconnection, and grounding by a linear operation.

  In the present embodiment, even if a vacuum leak occurs for some reason, the ground disconnection portion 10 is configured separately from the vacuum valve 1, so that the disconnection state can be maintained by the ground disconnection portion 10. Can be improved. In addition, since the ground disconnection portion is air-insulated, the cost can be reduced as compared with the case of vacuum insulation. Further, the current interruption is not performed in the air, but all can be performed in the vacuum valve 1, and the ground disconnection portion 10 in the air does not need to have the interruption performance, and the entire apparatus can be downsized. realizable.

  Moreover, in this embodiment, the electric shock of the operator is prevented by covering the periphery of the switch unit cast with the solid insulator 30 with the grounded metal container 31. In addition, instead of covering with a grounded metal container 31 as described later, safety can be ensured by setting the surface to the ground potential by applying a conductive paint having the ground potential.

  In this embodiment, the voltage and current are turned on and off in the vacuum valve 1 by a pair of contacts, but a plurality of pairs of contacts such as two pairs of contacts may be used.

  In the present embodiment, the flexible conductor 15 is used. However, instead of the flexible conductor 15, a normal conductor is used, and a slidable contactor is disposed between the movable side holder 7B and the like. It can also be made into a simple structure.

  In the present embodiment, the spring contact is disposed on the ground disconnection portion movable electrode 12, but a spring contact can be disposed on the fixed electrode side instead.

  Further, in this embodiment, the three positions of closed / disconnected / grounded are switched at the ground disconnecting part, but it may be possible to serve as the disconnecting state in the previous grounding state depending on the installation location of the switchgear. It is also possible to switch between two positions: closed and grounded.

  In the present embodiment, the ground disconnection part 10 is used together with the vacuum valve 1, but the ground disconnection part 10 itself can be applied to other than the vacuum valve 1.

  Next, an example in which the first embodiment of the switchgear of the present invention is applied to a three-phase, three-circuit circuit switching switchgear will be described with reference to FIGS.

  In order to construct a switch unit in which three switch units for three phases of alternating current are arranged adjacently and connect the rows of panels with solid insulation buses, a bus bushing 40A is provided for each AC phase as shown in FIG. , 40B, 40C are displaced so that the buses of the respective phases do not overlap, and the bushing side fixed electrode 11 and the bus bushing are connected by the internal bus 70, respectively. In FIG. 7, the insulating sealant 35 is disposed to prevent the entry of high-humidity air and fouling substances that may deteriorate the insulation characteristics of the portion.

  In addition, as shown in FIG. 7, if the solid insulator 30B is combined with the solid insulator 30 after casting the solid insulator 30 as a structure different from the solid insulator 30, the casting workability of the solid insulator 30 is improved. To do.

  FIG. 8 shows an example in which the switch unit shown in FIG. 7 is the switch unit 61A, 61B, 61C, and the same phase is connected by the solid insulated buses 60A, 60B, 60C to form a switch circuit for switching three-phase three circuits. Is shown.

  FIG. 9 is a front view of the three-phase three-circuit switching switchgear configured in FIG. Since a switch unit for switching between three phases and three circuits is configured by combining small and lightweight switch units of similar structure, the assembly workability is excellent.

  A second embodiment of the switchgear of the present invention will be described with reference to FIGS. In the present embodiment, the two ground disconnecting portions 10 and 10A and the vacuum valve 1 are combined to constitute a bus bar dividing board. Specifically, a second ground disconnection portion 10A is provided on the opposite side of the ground disconnection portion 10 of the vacuum valve 1 of the first embodiment shown in FIG. A connecting conductor 17 is provided for electrically connecting the intermediate fixed electrode 13A of the ground disconnecting part 10A. The first grounding disconnecting part 10 and the second grounding disconnecting part 10A can be operated individually, and can be switched to the three positions of closing, disconnecting and grounding independently. FIG. 11 is a plan view of the structure shown in FIG. The first ground disconnection portion 10, the vacuum valve 1, and the second ground disconnection portion 10 </ b> A are molded together with a solid insulator 30. As shown in FIG. 11, the vacuum valve 1 and the second ground disconnection portion 10A are bent into the space in the switch unit and connected with a conductor, so that the connection conductor 17 that is at a high voltage can be sufficiently connected from the air. The switch unit is prevented from increasing in size while being separated.

  The operation of the second embodiment of the switchgear of the present invention configured as described above will be described with reference to FIGS.

  In FIG. 12, the first bushing side fixed electrode 11 is connected to the ground disconnection portion fixed contact 51A, the first ground disconnection portion movable electrode 12 is connected to the ground disconnection portion movable contact 53A, and the first ground side fixed electrode 14 is connected to the ground disconnection. The fixed side electrode 6A of the vacuum valve 1 corresponds to the partial ground contact 52A, and the current switching unit fixed contact 54A, and the cable bushing 42 is connected to the cable head 56A. The second bushing side fixed electrode 11A is connected to the ground disconnection portion fixed contact 51B, the second ground disconnection portion movable electrode 12A is connected to the ground disconnection portion movable contact 53B, and the second ground side fixed electrode 14A is connected to the ground disconnection portion ground. This corresponds to the contact 52B. As shown in the figure, the first ground disconnection portion 10 and the second ground disconnection portion 10A can be independently switched to the ground and disconnection positions.

  FIG. 13 shows a blocking state. In the input state shown in FIG. 10, a load current is passed from the bus bushing 40 to the bus bushing 40A via the ground disconnection portion 10, the vacuum valve 1, and the ground disconnection portion 10A. In this state, when a short circuit occurs on the bus side connected to the bus bushing 40 and a large accident current flows, the accident current is interrupted by shutting off the vacuum valve 1 as shown in FIG.

  FIG. 14 shows a disconnected state. The second ground disconnection part movable electrode 12A, the second bushing side fixed electrode 11A, and the second ground side fixed electrode 14A are not conductive, and the second ground disconnection part movable electrode 12A The second grounding disconnecting portion movable electrode 12A is moved to the position where the gap between the second bushing side fixed electrode 11A is large and the gap between the second grounding disconnecting portion movable electrode 12A and the second grounding side fixed electrode 14A is small. It becomes a disconnection state by driving downward.

  At this time, since the bus bushing 40 and the second bus bushing 40A are disconnected at two points of the vacuum valve 1 and the second ground disconnection portion 10A, the reliability is high. Further, the withstand voltage between the second ground disconnection portion movable electrode 12A and the second ground side fixed electrode 14A is designed to be lower than the withstand voltage between the fixed side electrode 6A of the vacuum valve 1 and the movable side electrode 6B. As a result, a highly reliable structure with a priority on ground fault can be obtained.

FIG. 15 shows a grounding state. First, the second ground disconnection part movable electrode 12A is driven downward in the drawing to the position where the second ground disconnection part movable electrode 12A and the second ground side fixed electrode 14A come into contact with each other.
Next, when the vacuum valve 1 is turned on, the first bus bushing 40 has the ground disconnection part 10, the vacuum valve 1, the connection conductor 17, the second intermediate fixed electrode 13A, the ground disconnection part movable electrode 12A, It is grounded via the ground side fixed electrode 14A. At this time, even if the bus bushing 40 is in the power-applied state, since the final closing operation is performed by the vacuum valve 1, no short-circuit current input capacity is required for the second ground disconnection portion 10A.

  When the second bus bushing is grounded, the first ground disconnecting portion and the second ground disconnecting portion may be reversed and the same process may be performed. That is, first, the state shown in FIG. 10 is shifted to the shut-off state shown in FIG. 13, and then the first ground disconnection portion movable electrode 12 is driven downward in the drawing to contact the ground-side fixed electrode 14, and then the vacuum valve 1, the bus bushing 40 passes through the ground disconnection portion 10 </ b> A, the vacuum valve 1, the flexible conductor 15, the first intermediate fixed electrode 13, the ground disconnection portion movable electrode 12, and the ground side fixed electrode 14. Grounded.

  Next, a third embodiment of the switchgear of the present invention will be described with reference to FIGS. In this embodiment, as shown in FIG. 16, the bushing-side fixed electrodes 11 of the ground disconnection portion 10 are electrically connected as a high-voltage conductor in place of the switchgear bus bushing according to the first embodiment of the present invention. The common bus bar conductor 50 is provided, and a plurality of these units are casted together with a solid insulator. By using the common bus conductor 50, the bus bushing is not required, the amount of molding can be reduced as a whole, and no bus is required. Therefore, the entire switch gear can be miniaturized, and the number of parts is reduced, leading to cost reduction.

  FIG. 17 and FIG. 18 show an example in which a three-circuit switching switchgear unit for three-phase AC and one-phase is configured by using the third embodiment, and grounding disconnecting portions 10A, 10B, 10C, vacuum valves 1A, 1B, 1C. , Flexible conductors 15A, 15B, 15C and the like were cast together with solid insulator 30, and cable bushings 42A, 42B, 42C were formed at the same time. By being able to perform batch casting, the overall mold amount is reduced and the cost is reduced.

  Further, in this embodiment, since the switch unit of the same phase can be molded integrally, the number of castings can be reduced.

  19 and 20 show a fourth embodiment of the switchgear of the present invention. In the present embodiment, the bus bushing 40 and the cable bushing 42 are pulled out in the same direction. 20, one switch unit 61D shown in FIG. 19 is used, and the switch unit assembly for three circuits in which the bus bushes 40 are connected to each other by solid-insulated buses 60A, 60B, and 60C. Three phases were arranged parallel to the direction (in the same plane). Such an arrangement leads to space saving as a whole as compared with the case of the linear arrangement, and the length of the bus bar to be used is also shortened, thereby reducing the cost. Also, by molding in units of switch units, the amount of molding per switch gear can be reduced as compared with the case of molding a plurality of switch units integrally, leading to weight reduction and cost reduction. Furthermore, in this embodiment, an operation mechanism (not shown) can be provided for each circuit in the left-right direction on the paper surface, and no unnecessary space is generated, and opening and closing operations are performed by collectively opening and closing the three phases across the switch unit assembly. The installation area of the vessel can be greatly reduced.

  A fifth embodiment of the switchgear of the present invention will be described with reference to FIGS. FIG. 21 shows a case where the ground disconnecting portion 10 is in the on state, and FIG. 22 shows a case where the ground disconnecting portion 10 is in the ground state. In FIG. 21 and FIG. 22, it replaces with the metal container 31 and comprises by providing the conductive coating 32 on the outer surface of the solid insulator 30. In order to reduce the weight of the solid insulator 30 as much as possible, in the ground disconnection portion 10, the bus bar side shield 71, the vacuum valve side shield 72, and the operation rod side shield 73 are embedded in the solid insulator 30, and the ground disconnection portion 10 and the same axis. In FIG. 21, the bus-side shield 71 and the vacuum valve-side shield 72 are a high electric field portion 74 in the air at the time of turning on when the ground disconnecting portion movable electrode 12 is turned on and the vicinity of the center between the electrodes filled with air. By reducing the electric field of the part, the insulation performance is ensured and the thickness of the solid insulator is reduced. In FIG. 22, a large voltage is applied between the intermediate fixed electrode 13 that is at the ground potential and the bushing-side fixed electrode 11 connected to the bus side, and in the air in the vicinity of the tips of both fixed electrodes. Electric field concentrates. Therefore, by arranging the bus bar side shield 71 and the vacuum valve side shield 72 so as to surround the intermediate fixed electrode 13 and the bushing side fixed electrode 11 serving as the electric field concentration portion, the electric field concentration is alleviated and the insulation performance is ensured. Furthermore, in FIG. 21, the operation rod side shield 73 reduces the electric field on the operation rod side of the flexible conductor 15 and the intermediate fixed electrode 13 to ensure the insulation performance around the operation rod. The above configuration can be applied in common to the above-described embodiments. Moreover, by burying and arranging these shields, the insulation performance can be maintained even when the thickness of the mold member is reduced, and downsizing of the device particularly in the radial direction can be realized.

  21 and 22 show an example of the guide 81 arranged so that the radial position of the ground disconnection portion movable electrode 12 is not shifted. By arranging the guide 81 inside the ground disconnection portion intermediate fixed electrode, the positional accuracy of the ground disconnection portion movable electrode 12 is enhanced.

  In each of the above embodiments, a configuration that is inverted in the vertical direction is shown, but in each embodiment, it is possible to invert the top and bottom.

1, 1A, 1B, 1C Vacuum valve 2A Fixed ceramic insulating cylinder 2B Movable ceramic insulating cylinder 3A Fixed end plate 3B Movable end plate 4A Fixed electric field relaxation shield 4B Movable electric field relaxation shield 5 Arc shield 6A Fixed electrode 6B Movable side electrode 7A Fixed side holder 7B Movable side holder 8 Bellows shield 9 Bellows 10, 10A, 10B, 10C Ground disconnection portion 11, 11A Bushing side fixed electrode 12, 12A Ground disconnection portion movable electrode 13, 13A Intermediate fixed electrode 14, 14A Ground side fixed electrode 15 Flexible conductor 16 Spring contact 17 Connection conductor 20 Vacuum valve operation rods 21, 21A Ground disconnection portion operation rods 30, 30A, 30B Solid insulator 31 Metal container 35 Insulation sealant 40, 40A, 40B , 40C Bus Bushing 41 Bus Bushing Conductor 42, 42A, 42B, 42C Cable bushing 43 Cable bushing center conductor 50 Common bus conductors 51A, 51B, 51C Ground disconnection portion fixed contact 52A, 52B, 52C Ground disconnection portion ground contact 53A, 53B, 53C Ground disconnection portion movable Contact 54A, 54B, 54C Current switching unit fixed contact 55A, 55B, 55C Current switching unit movable contact 56A, 56B, 56C Cable head 60A, 60B, 60C Solid insulation bus 61A, 61B, 61C, 62D Switch unit 70 Internal bus 71 Bus-side shield 72 Vacuum valve-side shield 73 Operating rod-side shield 74 High-in-air section 75 in the air at the time of introduction 75 High-in-air section 81 in the ground at the time of guide

Claims (8)

A vacuum valve having a fixed electrode and a movable electrode, the inside of which is a vacuum;
Air having a ground disconnection portion movable electrode, a bus-side fixed electrode arranged on the bus-bar side, an intermediate fixed electrode electrically connected to an electrode in the vacuum valve, and a ground-side fixed electrode that is a ground potential and a grounding disconnector unit,
The ground disconnection part movable electrode can contact the bus-side fixed electrode, the intermediate fixed electrode and the ground-side fixed electrode,
The switch gear is characterized in that the ground disconnection portion movable electrode is linearly displaced at three positions of a closed position, a disconnect position, and a ground position. The switchgear according to claim 1,
An operating rod for a vacuum valve that transmits an operating force from an operating device to the movable electrode of the vacuum valve;
An operation rod for a ground disconnection part that transmits an operation force from an operating device to the ground disconnection part movable electrode,
A solid insulator covering the vacuum valve and the ground disconnection part;
A second solid insulator covering the periphery of the vacuum rod operating rod and the ground disconnection portion operating rod;
The switchgear further comprising a third solid insulator connected to the second solid insulator and the ground-side fixed electrode. The switchgear according to claim 2,
A switchgear characterized in that an insulating sealant is disposed between the solid insulator and the second solid insulator. The switchgear according to claim 1,
A solid insulator covering the vacuum valve and the ground disconnection part;
A switchgear further comprising a metal container covering the periphery of the solid insulator. The switchgear according to claim 4,
The switchgear characterized in that the metal container collectively covers the solid insulators for three phases arranged adjacent to each other. The switchgear according to any one of claims 2 to 5,
A movable side holder connected to each of the movable electrode of the vacuum valve and the operating rod for the vacuum valve;
A flexible conductor,
The switch gear, wherein the intermediate fixed electrode is electrically connected to the movable side holder via the flexible conductor. The switchgear according to claim 6, wherein
The switchgear is characterized in that the flexible conductor is disposed inside an operation rod side shield embedded in the solid insulator. The switchgear according to claim 7,
The switch gear, wherein the intermediate fixed electrode is disposed inside the operation rod side shield.

Images