JP5408551B2 - Gas insulated switchgear - Google Patents

Description

  The present invention relates to a gas insulated switchgear, and more particularly to a composite insulation structure between electrodes.

  Conventionally, in a gas insulated switchgear, downsizing of the device has been achieved by improving the withstand voltage performance between the electrodes of the switchgear using a composite insulating shield in which a metal shield is coated with an insulator.

  For example, in the gas insulated switchgear described in Patent Document 1, a disconnector having a movable electrode portion and a fixed electrode portion is housed in a grounded container filled with an insulating gas, and is opened so as to cover both electrode portions. Describes a structure in which a metal / dielectric integrated composite insulation shield provided with a dielectric coating is provided on the surface of a high electric field near the tip of the part. Further, Patent Document 1 describes a configuration in which the above-described composite insulating shield is provided on the movable electrode portion and only the metal shield is provided on the fixed electrode portion. As a result, an arc is generated only between the fixed-side metal shield and the movable contact provided on the movable-side electrode portion, thereby preventing damage to the dielectric due to the arc and improving the reliability of the apparatus.

JP 2004-222483 A

  However, in the above-described gas insulated switchgear, the movable and fixed electrodes and the composite insulation shield that covers the electrodes are connected so as to protrude perpendicularly to the main circuit conductor, respectively. There is a problem that the axial dimension of the switchgear is increased by the size of the electrode and the shield, and as a result, the overall size of the gas insulated switchgear is increased.

  Also, if the opposing movable side and fixed side shields are configured in the same shape, if a dielectric is provided only on the movable side shield, there will be a difference in the electric field strength between the movable side and the fixed side shield, and the entire gap The effect of reducing the electric field cannot be obtained. For this reason, in order to obtain the withstand voltage performance between the poles equivalent to the case where a dielectric is provided on the movable side and fixed side shields, it is necessary to increase the distance between the poles, and the device becomes larger in size. was there.

  The present invention has been made to solve the above-described problems, and provides a gas insulated switchgear that is smaller in size and improved in economy and reliability.

  In order to solve the above-mentioned problem, the invention according to claim 1 is a gas provided with any one switchgear of a disconnector, a ground switch, or a lightning arrester switch accommodated in a grounded container filled with an insulating gas. In the insulated switchgear, the switchgear includes a movable electrode formed in a hollow shape, a mover that linearly moves in the movable side electrode while maintaining electrical contact with the movable electrode, and the mover A fixed-side electrode that contacts and separates from the movable-side electrode, and a composite insulating shield in which a metal is coated with an insulator is provided around the movable-side electrode, and the fixed-side electrode is perpendicular to the moving direction of the mover. Arranged in the extended cylindrical conductor, an arc electrode is provided inside the fixed side electrode, a flat portion is formed on the surface of the cylindrical conductor facing the movable side electrode, and the flat portion is provided with the flat portion. Fixed side through which the mover is inserted Characterized in that the formation of the hole.

  The invention according to claim 2 includes a disconnector, a ground switch, and a lightning arrester switch that are housed in a grounded container filled with an insulating gas and arranged in a row at a predetermined interval in the vertical direction. In the gas-insulated switchgear, each of the disconnect switch, the ground switch, and the lightning arrester switch is configured such that the movable side electrode formed in a hollow shape and the movable side electrode are kept in electrical contact with the movable side electrode. A movable element that linearly moves in a horizontal direction, and a fixed-side electrode that is in contact with and away from the movable element, and a composite insulating shield that is coated with an insulator on a metal is provided around the movable-side electrode, and the fixed side The electrodes are respectively arranged at a predetermined interval in a common cylindrical conductor extending in a direction perpendicular to the moving direction of the mover, an arc electrode is provided inside the fixed side electrode, and the cylindrical shape is further provided. The movable side power of the conductor A flat portion is formed on a surface facing the pole, and a fixed side insertion hole through which the movable element is inserted is formed in the flat portion.

  The invention according to claim 3 is characterized in that, in the invention according to claim 2, the disconnecting switch is disposed above the ground switch and the lightning arrester switch.

  The invention according to claim 4 is the invention according to any one of claims 1 to 3, wherein the arc electrode is retracted from the fixed side insertion hole during the insertion operation of the mover, and the mover The tip of the arc electrode is returned to the same plane as the surface of the flat portion by a spring provided at the rear portion of the arc electrode during the separation operation from the fixed side electrode.

  According to the gas insulated switchgear of the present invention, the movable side electrode is provided with the metal / insulator shield, and the fixed side electrode is disposed in the cylindrical conductor also serving as the metal shield. The axial dimensions of the fixed-side electrode and the fixed-side shield covering the electrode are reduced, the withstand voltage performance between the electrodes is improved, and the overall gas-insulated switchgear can be reduced.

  Furthermore, since the cylindrical conductor that also serves as the fixed shield is shared by the disconnect switch, the ground switch, and the lightning arrester switch, the cost can be reduced by downsizing the device and reducing the number of parts.

It is the block diagram which showed the gas insulated switchgear which concerns on this invention. It is a principal part expanded sectional view of the gas insulated switchgear shown in FIG. It is an enlarged view of the stationary-side electrode part of the disconnector shown in FIG. It is A-A 'sectional drawing of the disconnector shown in FIG. FIG. 4 is a B-B ′ sectional view of the disconnector shown in FIG. 3. It is sectional drawing which shows the open circuit state of the disconnector shown in FIG. It is the characteristic view which compared the axial direction dimension of the conventional structure and the switchgear of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the entire gas insulated switchgear according to the present invention. Reference numeral 1 denotes an equipment tank. A bus tank 2 is connected above the equipment tank 1.

  In the bus tank 2, a bus 4 for three phases passes through the bus tank 2 in a direction perpendicular to the paper surface through a three-phase insulating spacer 3. The bus 4 is led into the equipment tank 1 through the main circuit conductor 5, the bus-side disconnector 6, and the penetrating main circuit conductor 7.

  The bus-side disconnector 6 includes a movable electrode 6a, a movable element 6b that is slidably inserted into the movable electrode 6a, and a fixed electrode 6c that contacts and separates from the movable element 6b. A disconnector operating portion 8 for operating the bus-side disconnector 6 is attached to the outside of the mounting plate 9, and the disconnector operating portion 8 and the mover 6b are connected via an insulating rod (not shown) that penetrates the mounting plate 9 in an airtight manner. Are connected.

  A movable side electrode 6 a of the busbar side disconnector 6 is attached to the inside of the attachment plate 9. The movable side electrode 6a is electrically connected to the main circuit conductor 5 and the bus bar 4 via the movable element 6b and the fixed side electrode 6c.

  Further, a penetrating main circuit conductor 7 is connected to the movable side electrode 6a. The penetrating main circuit conductor 7 is connected to a device in the device tank 1 through a communication hole that penetrates the bus tank 2 and the device tank 1 and an insulating spacer 10 that closes the communication hole.

  Inside the device tank 1, a main circuit conductor 11 and a cylindrical conductor 12 are fixed to the device tank 1 via insulators. Furthermore, the circuit breaker 13, the main circuit conductor 14 having one end connected to the lower part of the circuit breaker 13, and the line side disconnector 15 connected to the other end of the main circuit conductor 14 (hereinafter, the line side disconnector is simply referred to as DS). And a grounding switch 16 (hereinafter referred to as “ES”) and a lightning arrester switching device 17 (hereinafter referred to as “LA”). These devices are detachably attached to the device tank 1 as follows.

  The circuit breaker 13 is attached to the inside of the mounting plate 18, and the circuit breaker operation unit 20 is attached to the outside of the mounting plate 18.

  DS 15 and ES 16 are attached to the inside of the attachment plate 22, and a DS / ES operation section 23 for operating both is attached to the outside of the attachment plate 22. Further, an LA opening / closing device 17 is attached to the attachment plate 22 and is connected to an LA opening / closing device operating section 24 attached to the outside of the equipment tank 1.

  Behind the device tank 1 is a cable storage section 25, and a cable head 27 is attached to the upper end of the cable 26 stored in the cable storage section 25. The cable head 27 is connected to the main circuit conductor 11 via the connection portion 28. Further, a current transformer 29 is attached to the cable 26.

  FIG. 2 is an enlarged cross-sectional view of the main part of the gas insulated switchgear in FIG. 1 and shows details of the structure between the DS15, ES16 and LA switchgear 17 between the electrodes. In the equipment tank 1, DS 15, ES 16, and the LA opening / closing device 17 are arranged in this order from the top in a row with a predetermined insulation distance in the vertical direction. In addition, although the structure for one phase is described in the drawing, each of the three phases of DS15, ES16 and LA switchgear 17 is arranged with a predetermined insulation distance in the direction perpendicular to the paper surface.

  Each of the DS 15, ES 16, and LA switchgear 17 includes a movable side electrode part and a fixed side electrode part arranged to face the movable side electrode part. The movable electrode portion is electrically insulated in the open state, and forms an energization path in the closed state. On the other hand, each fixed side electrode part is connected to the common cylindrical conductor 12, and is in an electrically integrated state.

  Next, the movable side electrode part of DS15, ES16, and LA switchgear 17 will be described in detail. In the DS movable side electrode section 150, 150 a is a DS movable side electrode formed in a hollow shape, and is connected to the lower end of the main circuit conductor 14. The DS movable side slider 30 is connected to the right end of the DS movable side electrode 150a. Further, an annular spring 31 is wound around the DS movable slider 30 in a tensioned state. In addition, by arranging the DS 15 above the ES 16 and the LA switchgear 17 as in the present embodiment, the main circuit conductor 14 and the DS 15 are brought close to each other, and the layout is superior.

  The DS movable-side electrode 150a has an insulating operating rod 32 and a DS movable element 150b connected to the right end of the insulating operating rod 32 so as to pass through its axial center. The DS movable element 150 b is electrically connected to the DS movable side slider 30. A metal shield 33 is attached to the outer periphery of the DS movable electrode 150a. Further, an insulator coating 34 made of epoxy resin or the like is applied to the surface of the high electric field portion near the opening tip of the metal shield 33. The DS movable side electrode 150a is fixed to the wall surface of the equipment tank 1 via the DS support insulator 35 and the support fitting 36.

  Below the DS movable side electrode portion 150, an ES movable side electrode portion 160 is disposed with a predetermined insulation distance maintained. A ground conductor 38 is connected to the ES movable electrode 37 and is connected to a ground terminal (not shown). Since other configurations are the same as those of the DS movable side electrode unit 150, description thereof is omitted.

  An LA switchgear movable electrode portion 170 is disposed below the ES movable electrode portion 160 while maintaining a predetermined insulation distance. The LA movable side electrode 39 is fixed to the bottom of the equipment tank 1 via the LA support insulator 40. An LA element 41 is connected to the LA movable side electrode 39. Since other configurations are the same as those of the DS movable side electrode unit 150, description thereof is omitted.

  Next, the fixed electrode portions of the DS15, ES16, and LA switchgear 17 will be described in detail. The fixed side electrode portions are respectively arranged inside the cylindrical conductors 12 arranged in the vertical direction. The cylindrical conductor 12 is fixed to the bottom of the equipment tank 1 via a conductor support insulator 42. As described above, the cylindrical conductor 12 has a structure in which the high electric field portion is not provided in the gas by accommodating the lower end portion serving as the high electric field portion in the conductor support insulator 42. Since the configuration of the fixed-side electrode portion is the same for the DS15, ES16, and LA switchgear 17, only the fixed-side electrode portion 151 of the DS15 will be described here.

  FIG. 3 is an enlarged detailed view of the fixed side electrode portion 151 of the DS 15 shown in FIG. 2, and shows a closed state here. The cylindrical conductor 12 includes two members, a fixed shield part 12a and an electrode support part 12b. The DS fixed electrode 151a is fixed to the convex portion 12c of the electrode support portion 12b via a bolt. The DS fixed side slider 43 is connected to the left end of the DS fixed side electrode 151a. Further, an annular spring 44 is wound around the DS fixed side slider 43 in a tensioned state.

  An arc electrode 45 is disposed inside the DS fixed electrode 151a. At this time, the arc electrode 45 is disposed on the same axis as the DS mover 150b. A coil spring 46 is connected behind the arc electrode 45.

  FIG. 4 is a cross-sectional view taken along the line A-A ′ of the fixed electrode portion 151 of the DS 15 shown in FIG. 3. The fixed shield part 12a is provided with a flat part 47 on the surface facing the movable electrode part 150 to reduce the electric field.

  FIG. 5 is a B-B ′ cross-sectional view of the fixed electrode portion 151 of the DS 15 shown in FIG. 3, and the DS 15 is in a closed state in the drawing. At this time, the DS mover 150 b is inserted into the cylindrical conductor 12 while compressing the coil spring 46 so as to push the arc electrode 45. Further, the DS mover 150b and the DS fixed side slider 43 are in contact with each other and are in an electrically connected state.

  Next, the operation from the closed state of the DS 15 to the open state of the DS 15 shown in FIG. 6 will be described. When the DS mover 150b is moved to the left in the drawing by an operating device (not shown), the DS mover 150b and the DS fixed side slider 43 are separated, and the electrical connection is cut off. Immediately after the DS mover 150b and the DS fixed side slider 43 are separated, the arc electrode 45 follows the DS mover 150b in a contacted state by the bias of the coil spring 46 in the left direction. For this reason, no arc is generated between the DS mover 150 b and the DS fixed side slider 43.

  Thereafter, the DS mover 150 b further moves leftward, and an arc is ignited between the DS mover 150 b and the arc electrode 45 when the DS mover 150 b is separated from the arc electrode 45. At this time, the arc electrode 45 returns to a position on the same plane as the fixed side insertion hole 48 formed in the flat portion 47 of the fixed side shield portion 12a by the bias of the coil spring 46, and in the vicinity of the fixed side insertion hole 48 To reduce the electric field. By the operation as described above, the DS 15 reaches the open circuit state shown in FIG.

  FIG. 7 is a characteristic diagram showing the axial dimensions of the switchgear in the conventional example and the present invention (hereinafter, the switchgear refers to any one of DS15, ES16, or LA switchgear 17). In the conventional examples shown on the horizontal axis, (a) is a metal shield on both the movable side and the fixed side, (b) is a metal / insulator shield on both the movable side and the fixed side, and (c) is a metal / insulator on the movable side. The shield has a metal shield on the fixed side.

  Each of the conventional examples (a) to (c) has a metal shield having the same shape on the movable side and the fixed side, and further has an electrode (not shown) inside the metal shield. In addition, the right side in the figure is the fixed side, and a conductor is connected behind the fixed side shield. In contrast, in the present invention (d), as described above, the metal / insulator shield is arranged on the movable side, and the cylindrical conductor also serving as the metal shield is arranged on the fixed side. Further, a flat portion is formed on the surface of the cylindrical conductor facing the movable side, and a fixed electrode and an arc electrode are provided in the cylindrical conductor.

  Here, the distance between the electrodes of each component is L1. Also, L2 is obtained by adding L1 to the axial dimension of the fixed shield and the radial dimension of the fixed conductor, and this is indicated on the vertical axis.

  In comparing L2 in each configuration, when the dimension is normalized with L2 = 100 based on the conventional example (a), an inter-electrode distance L1 = 55 is obtained. Further, in the conventional example (b), the insulator coating applied to the movable side and fixed side metal shields reduces the electric field strength at the shield end and improves the withstand voltage performance, so that it is reduced to L1 = 22. As a result, L2 = 66 is obtained.

  In the conventional example (c), both the movable and fixed electrode portions and the shield facing each other are configured in the same shape, and the metal / insulator shield is used only on the movable side. Differences in the electric field strength occur, and the entire electric field reduction effect between the electrodes cannot be obtained. As a countermeasure, it is necessary to make L1 = 50 as large as possible in order to ensure the withstand voltage performance between the poles equivalent to (a) and (b). For this reason, L2 = 94, and as a result, the effect of improving the withstand voltage performance by the insulator coating provided on the movable side is not sufficiently exhibited.

  On the other hand, in the present invention (d), the electric field strength is reduced by a metal / insulator shield on the left movable side in the drawing, and a cylindrical conductor also serving as a metal shield is arranged on the fixed side. As a result, the axial dimension of the shield that has conventionally been provided separately from the conductor is reduced.

  In addition, since there is no conventional metal shield end portion on the fixed side and a flat portion is formed on the surface facing the movable side of the cylindrical conductor, the electric field strength is greatly reduced. Furthermore, since the left end of the movable arc electrode arranged in the cylindrical conductor returns to the same plane as the fixed insertion hole formed in the flat part when the switchgear is opened, the electric field strength on the fixed side Is further reduced. In other words, the electric field strength is reduced on the fixed side without the insulator and only the metal shield and on the movable side having the metal / insulator shield.

  As a result, L1 = 22 equivalent to the conventional example (b) having the metal / insulator shield on the movable side and the fixed side can be obtained. As a result, L2 = 44 can be obtained, and the axial dimension of the switchgear can be reduced as compared with the conventional configuration. As a result, the overall size of the gas-insulated switchgear can be reduced.

  Further, in this embodiment, only the cylindrical conductor serving as a metal shield on the fixed side, or the cylindrical conductor is coated with an insulator coating having a thickness of 1 mm or less, thereby reducing the usage of the insulator. Therefore, it is possible to reduce the cost and damage due to the arc of the insulator, and to improve the reliability of the apparatus.

  Furthermore, in this embodiment, since the cylindrical conductor that also serves as the fixed shield is shared by the DS15, ES16, and LA switchgear 17, the fixed shield is arranged separately for each switchgear as in the prior art. Cost reduction can be achieved by downsizing the equipment and reducing the number of parts.

1 equipment tank 2 bus tank 3 three-phase insulating spacer 4 bus 5 main circuit conductor 6 bus side disconnector 7 penetrating main circuit conductor 8 disconnector operation section 9 mounting plate 10 insulating spacer 11 main circuit conductor 12 cylindrical conductor 12a fixed shield Part 12b electrode support part 12c convex part 13 circuit breaker 14 main circuit conductor 15 DS
150 DS movable side electrode portion 150a DS movable side electrode 150b DS mover 151 DS fixed side electrode portion 151a DS fixed side electrode 16 ES
17 LA switchgear 18 Mounting plate 20 Circuit breaker operation part 22 Mounting plate 23 DS / ES operation part 24 LA switchgear operation part 25 Cable storage part 26 Cable 27 Cable head 28 Connection part 29 Current transformer 30 DS movable side slider Reference Signs List 31 Annular Spring 32 Insulating Operation Rod 33 Metal Shield 34 Insulator Cover 35 DS Support Insulator 36 Support Bracket 160 ES Movable Side Electrode 37 ES Movable Side Electrode 38 Ground Conductor 170 LA Movable Side Electrode 39 LA Movable Side Electrode 40 LA Support Insulator 41 LA element 42 Conductor support insulator 43 DS fixed side slider 44 Annular spring 45 Arc electrode 46 Coil spring 47 Flat part 48 Fixed side insertion hole

Claims (4)

  In a gas-insulated switchgear having any one switchgear of a disconnector, a ground switch, or a lightning arrester switch housed in a grounded container filled with an insulating gas, the switchgear is formed in a hollow shape A movable side electrode; a movable element that linearly moves in a horizontal direction while maintaining electrical contact with the movable side electrode in the movable side electrode; and a fixed side electrode that is in contact with and away from the movable element. A composite insulation shield in which an insulator is coated on a metal is provided around the fixed electrode, and the fixed side electrode is disposed in a cylindrical conductor extending in a direction perpendicular to the moving direction of the mover. An arc electrode is provided inside, a flat portion is formed on the surface of the cylindrical conductor facing the movable side electrode, and a fixed insertion hole through which the movable element is inserted is formed in the flat portion. Gas insulated opening and closing characterized by Location.   In a gas insulated switchgear having a disconnector, a grounding switch, and a lightning arrester switch, which are housed in a grounded container filled with an insulating gas and arranged in a line at a predetermined interval in the vertical direction, the disconnector Each of the ground switch and the lightning arrester switch includes a movable electrode formed in a hollow shape, and a mover that linearly moves in the movable side electrode in a horizontal direction while maintaining electrical contact with the movable electrode. The movable side electrode is provided with a fixed side electrode that is in contact with and separated from the movable element, and a composite insulating shield in which a metal is coated with an insulator is provided around the movable side electrode, and the fixed side electrode is moved in the moving direction of the movable element. Are arranged in a common cylindrical conductor extending in a vertical direction with a predetermined interval, an arc electrode is provided inside the fixed side electrode, and is opposed to the movable side electrode of the cylindrical conductor. Flat part on the surface A gas-insulated switchgear characterized in that a fixed-side insertion hole is formed in the flat part and into which the movable element is inserted.   The gas-insulated switchgear according to claim 2, wherein the disconnector is disposed above the ground switch and the lightning arrester switch.   The arc electrode is retracted from the fixed side insertion hole during the insertion of the mover, and the tip of the arc electrode is moved by a spring provided at the rear of the arc electrode during the separation operation of the mover from the fixed side electrode. The gas-insulated switchgear according to any one of claims 1 to 3, wherein the gas-insulated switchgear returns to the same plane as the plane of the flat portion.

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