JP6094028B2 - Vacuum circuit breaker - Google Patents

Description

  The present invention relates to a vacuum circuit breaker, and more particularly to a vacuum circuit breaker that houses a vacuum valve in an insulating case.

  The structure of an insulating case (Patent Document 1) in a conventional vacuum circuit breaker is shown in FIGS. As shown in FIG. 8, this patent document discloses an insulating case 13 in which a vacuum valve 14 is accommodated in a form sandwiched between two insulating frames 11a and 11b. The movable electrode rod 27 connected to the vacuum valve 14 is connected to a driving device (not shown) via an insulating rod 19. One end of a flexible conductor (not shown) is connected between the insulating rod 19 and the movable electrode rod 27 toward a conductor disposed outside the insulating case, and the periphery thereof is covered with a conductor cover 18.

  In addition, as shown in FIG. 9, the insulating case 13 includes a first insulating frame 11a having a substantially U-shaped cross section perpendicular to the longitudinal direction and a second insulating frame 11b having the same shape as the first insulating frame 11b with an interval therebetween. It arrange | positions so that the opening side of may oppose. In this way, the insulating case 13 is given mechanical strength against electromagnetic force acting on the single pole portion of the circuit breaker. Further, in another embodiment of Patent Document 1, as shown in FIG. 10, notches are formed in the insulating frames 24a and 24b in order to convect the gas heated by the heat generated during energization and improve the cooling performance. The structure provided with the part 21 is disclosed. These insulating cases 13 are arranged in parallel for three phases.

  Further, in Patent Document 2 (not shown), a member that supports the stationary terminal portion of the vacuum valve and a pair of insulating barrier members that are arranged substantially in parallel and insulate the space between the phases on both sides of the vacuum valve are integrated. A mold frame cast or molded is disclosed. By making the both sides of this pair of insulating barrier members open, it becomes possible to connect the conductor connected to the single pole part of the vacuum valve from either of the open parts, and connect the conductor at the shortest distance to make the conductor A configuration for minimizing the length is described.

WO2009 / 125467 JP2008-277139

  In the configuration in which two insulating frames are arranged above and below the vacuum valve as in Patent Document 1, the other end of the conductor having one end connected to the movable electrode rod is placed at the shortest distance from the circuit arranged outside the insulating case. In order to connect, it is necessary to provide a through hole or a notch through which the conductor passes in the insulating case, and the strength of the insulating case may be weakened. In addition, when a conductor is routed horizontally from the vacuum valve so as to pass through the gap between the insulating frames and is connected to a main circuit arranged above and below the vacuum valve, the distance between the insulating frames arranged for three phases in the horizontal direction. Must be taken for conductor routing, and there is a concern that the conductor length also becomes longer.

  In addition, in the configuration in which the notch portions are provided on the movable electrode rod side and the fixed electrode rod side, the mechanical strength of the frame may be lowered, and the notch portion is local, so that gas convection is smooth. It is difficult to occur and there is a concern that a sufficient cooling effect cannot be obtained.

  Further, in Patent Document 2, since the mold frame is made of one member integrally cast with an insulator, the vacuum valve is fixed in a state where the entire vacuum valve is housed inside the mold frame, so that the assemblability is deteriorated. There are concerns. In addition, when applied to a large-capacity vacuum circuit breaker, it is necessary to have a structure that also takes into account the strength of the mold frame.

  In order to solve the above-described problems, a vacuum circuit breaker according to the present invention has a vacuum valve disposed horizontally in a tank sealed with an insulating gas, and the movable side terminal and the fixed side terminal of the vacuum valve are respectively connected to the movable side. The vacuum valve is housed in an insulating case, connected to a conductor and a fixed-side conductor. The insulating case includes a first insulating frame having a substantially U-shaped cross section, and a second insulating frame symmetrical to the first insulating frame. In the vacuum circuit breaker in which each of the two insulating frames is opposed to each other with an opening having a substantially U-shaped cross-section facing each other, the two insulating frames are substantially in cross-section. A cutout portion for passing the movable side conductor and the fixed side conductor is provided on one or both sides of the upper and lower ends of the U-shape, and the movable side conductor is machined by a bolt on the two insulating frames. For fixing A rib, a mounting end surface for mechanically fixing the stationary conductor with a bolt, and a tank mounting portion for mechanically fixing the insulating frame to the tank with a bolt. To do.

  Further, a reinforcing rib is formed over the entire circumference of the upper and lower end portions of the two insulating frames having a substantially U-shaped cross section.

  Further, the two insulating frames are characterized in that a through-hole portion is provided in the central side of the substantially U-shaped cross section.

  Since the horizontally disposed vacuum valve is covered with two symmetrical, half-divided insulating frames from the left and right, and there is also a gap between the upper and lower sides of the vacuum valve and the inner periphery of the insulating frame and the outer periphery of the vacuum valve, When a heat source is placed below the vacuum valve, or even if heat is generated by the movable conductor, fixed conductor, vacuum valve, etc., the heated insulating gas flows upward in the two insulating frames, so natural convection Is likely to occur, and the cooling performance is improved.

  In addition, because the cutouts are provided on the two sides of the upper and lower ends of the substantially U-shaped cross section of the insulating frame, the movable side and fixed side conductors are connected to the main circuit arranged above and below the vacuum valve at the shortest distance. it can. In addition, a mounting rib for mechanically fixing the movable side conductor to the insulating frame, a mounting end surface for mechanically fixing the fixed side conductor, and a tank mounting portion for mechanically fixing the insulating frame to the tank are provided. Thus, since each conductor and tank are integrated with the insulating frame, the mechanical strength can be maintained even if the insulating frame has a notch.

  Further, since the two insulating frames are attached to the movable side conductor, the fixed side conductor, and the vacuum valve in a preassembled state so as to be fitted from the left and right sides of the vacuum valve, the attachment position can be easily adjusted and the assemblability is improved.

  Further, since the reinforcing rib is provided on the entire periphery of the insulating frame, the mechanical strength of the insulating frame can be further improved.

  Further, by providing the through hole in the central side of the substantially U-shaped cross section of the insulating frame, the convection of the insulating gas is more likely to occur around the insulating frame, and the cooling performance can be further improved. .

It is side sectional drawing which shows the vacuum circuit breaker which concerns on this invention, and the gas insulated switchgear which accommodated this. It is an enlarged view of the vacuum circuit breaker periphery of FIG. 1 is an external perspective view of a vacuum circuit breaker according to the present invention. FIG. 3 is a cross-sectional view taken along the line AA of FIG. 2 in which only the insulating case is cut and the vacuum valve is shown by a virtual circle. FIG. 3 is a cross-sectional view taken along the line B-B of FIG. 2, showing only an insulating case, showing an insulating rod in a virtual circle, and showing a movable conductor and mounting ribs. It is a top view of the insulation frame concerning the present invention. It is a side view of the insulation frame concerning the present invention. It is a sectional side view of the conventional vacuum circuit breaker. It is a perspective view which shows only the insulation frame of FIG. It is a perspective view which shows the other Example of the insulation frame of FIG.

  A vacuum circuit breaker embodying the present invention and a gas insulated switchgear using the same will be described with reference to the drawings as appropriate. In FIG. 1, a gas-insulated switchgear 30 has a tank 31 divided into a bus room 33 and an equipment room 34, and each is sealed with an insulating gas.

  From this, the main circuit structure in the tank 31 is demonstrated along an electricity supply path | route. On the bus bar chamber 33 side, first, the current applied from the bus bar conductor 35 passes through the conductor 36 and flows to the fixed side contact 37a of the disconnector 37 with a grounding mechanism. Furthermore, the spacer conductor 41 passing through the three-phase spacer 39 through the blade 37b (current “off” state in the drawing) of the disconnector 37 with a grounding mechanism and the spacer upper conductor 38 is energized from the fixed contact 37a.

  On the equipment chamber 34 side, current flows from the spacer conductor 41 through the conductor 42 and is energized to the movable conductor 44 and the vacuum valve 46 of the vacuum circuit breaker 43. Furthermore, it is configured to be connected to the fixed-side conductor 48, the current transformer 49, and the cable socket 50. Here, both side surfaces (in the depth direction of the paper surface) of the vacuum valve 46 are covered by two insulating frames 52 having the same shape, which will be described later, but the insulating frame 52 on one side (front side of the paper surface) is illustrated for convenience of explanation of the structure. Omitted.

  Next, the structure of the vacuum circuit breaker 43, which is the main part of the present invention, will be described. In FIG. 2, a vacuum valve 46, which is a blocking part of the vacuum circuit breaker 43, has fixed and movable electrodes (not shown) that can be contacted and separated. The movable lead 45 connected to the movable electrode is mechanically connected to a driving device (not shown) via an insulating rod 56 and a bellows 64.

  The movable lead 45 is mechanically and electrically connected to a movable conductor 44 in which a movable contact is accommodated. The movable conductor 44 is fixed to a mounting rib 55 provided on an insulating frame 52 described later by bolts 57. Further, the insulating frame 52 has a tank mounting portion 59 and is fixed to the tank flange 31 a by a bolt 60.

  On the other hand, a fixed-side conductor 48 is mechanically and electrically connected to a fixed-side lead 47 connected to a fixed-side electrode (not shown) by a bolt 63. Further, the fixed-side conductor 48 is fixed to the mounting end surface 61 of the insulating frame 52 with bolts 62.

  As shown in FIG. 5, the vacuum valve 46 is accommodated in an insulating case 51 including two insulating frames 52 having a substantially U-shaped cross section and a symmetrical shape. Here, the “substantially U-shaped cross section” refers to a shape including an upper end side 52a, a central side 52b, a lower end side 52c, and a reinforcing rib 52d of the insulating frame 52. Further, as shown in FIG. 3, the two insulating frames 52 are arranged so that the openings having a substantially U-shaped cross section face each other with a gap therebetween. In other words, the both sides of the vacuum valve 46 are configured to be covered with the insulating frames 52 that are halved from the left and right. The insulating frame 52 is formed of, for example, an epoxy resin.

  Next, the detailed structure of the insulating frame 52 will be described. Although the two insulating frames 52 have a symmetrical shape, their basic shapes are the same, so only the structure of one insulating frame will be described here.

  As shown in FIG. 4, a gap for convection of the insulating gas is provided between the inner periphery of the insulating frame 52 and the outer periphery of the vacuum valve 46. Further, the sides 52a and 52c are formed in an arc shape, and a gas is introduced between the insulating frame 52 and the vacuum valve 46 by providing a through hole 65 in the central side 52b having a substantially U-shaped cross section of the insulating frame 52. The convection is further improved.

  In this embodiment, the side 52b is formed on a straight line. By doing so, the distance between the phases of the vacuum valves 46 arranged in the horizontal direction for three phases is reduced. However, the shape of the side 52b is not limited to this, and may be formed in an arc shape, for example.

  As shown in FIGS. 3 and 5, a notch 53 for allowing the movable conductor 44 to pass is formed in the side 52 a at the upper end and the side 52 c at the lower end of the substantially U-shaped cross section. In the present embodiment, the movable conductor 44 is connected to the main circuit through the notch 53 formed in the upper end side 52a. By providing a notch 53 in the lower end side 52c having a substantially U-shaped cross section of the insulating frame 52, the position of the insulating rod 56, bellows 64, and movable lead 45 during assembly can be adjusted, as will be described later. The fastening operation by the bolts 57 of the movable conductor 44 and the mounting rib 55 can be easily performed.

  A cutout portion 54 for allowing the fixed-side conductor 48 to pass therethrough is formed on the side 52 c at the lower end of the insulating frame 52. In addition, the reinforcing rib 52d is formed in the perimeter of the edge | side 52a and the edge | side 52c of the insulation frame 52 with a notch part.

  As shown in FIGS. 5 to 7, the insulating frame 52 is provided with mounting ribs 55 for mechanically fixing the movable conductor 44 and the insulating frame 52. Further, as shown in FIGS. 3, 6, and 7, a mounting end surface 61 for mechanically fixing the stationary conductor 48 and the insulating frame 52, and a tank for mechanically fixing the insulating frame 52 to the tank flange 31a. A mounting portion 59 is formed. By doing so, the insulating frame 52 is structured to be integrally fixed at three locations, that is, the movable side conductor 44, the fixed side conductor 48, and the tank flange 31a. Since the movable conductor 44 and the fixed conductor 48 are mechanically firmly fixed to the insulating frame 52, it is necessary to use a rigid conductor. In this embodiment, a plate-like conductor is used.

  Next, an assembly procedure for housing the vacuum valve 46 in the insulating case 11 as shown in FIG. 3 will be described. First, with respect to the movable side conductor 44, the fixed side conductor 48, and the vacuum valve 46 in a pre-assembled state, one of the two insulating frames 52 is fitted from either the left or right side of the vacuum valve 46 as shown in FIG. 48 and the attachment end surface 61 of the insulating frame 52 are brought into contact with each other. Then, the fixed side conductor 48 and the mounting end surface 61 of the insulating frame 52 are fixed by tightening from the outside of the insulating frame 52 with two bolts 62.

  On the other hand, the insulating frame 52 and the movable conductor 44 are fixed by tightening two bolts 57 in the direction of the movable conductor 44 from the mounting rib 55 side, as shown in FIGS. At this time, since the left and right side surfaces of the vacuum valve 46 are still open spaces, the bolts 57 can be easily fastened.

  Similarly, as shown in FIG. 2, the other insulating frame 52 is brought into contact with the fixed side conductor 48 so as to be fitted from either the left or right side of the vacuum valve 46, and the fixed side conductor 48 and the mounting end surface 61 are connected to the insulating frame 52. It is fixed by two bolts 62 from the outside. By doing so, the vacuum valve 46 is covered with the insulating case 51 including the two insulating frames 52 as shown in FIG.

  As shown in FIGS. 3 and 5, the notch 53 is provided in the insulating frame 52, so that the movable side conductor 44 and the mounting rib 55 of the other insulating frame 52 can be fitted with a tool from the notch 53. It is fixed by inserting and fastening with bolts 57. At this time, the space on the tank mounting portion 59 side in the insulating frame 52 is not closed but opened by the tank flange 31a shown in FIG. Therefore, the movable conductor 44 and the mounting rib 55 can be fastened by the bolts 57 from the tank mounting portion 59 side of the insulating frame 52.

  After the fixing side conductor 44 and the mounting rib 55 are fixed, the tank mounting portions 59 of the two insulating frames 52 are finally fixed to the tank flange 31a with a total of four bolts 60 as shown in FIG.

  With such a procedure, as shown in FIG. 3, one fixed-side conductor 48 and two attachment end surfaces 61 of the insulating frame 52 are fixed with a total of four bolts 62. Further, as shown in FIG. 5, one movable-side conductor 44 and the mounting ribs 55 of the two insulating frames 52 are fixed with a total of four bolts 57. Further, as shown in FIG. 2, the tank mounting portion 59 of the tank flange 31 a and the two insulating frames 52 is fixed by a total of four bolts 60.

  As described above, since the insulating frame 52 is mechanically fixed integrally at the three positions of the movable side conductor 44, the fixed side conductor 48, and the tank flange 31a, the mechanical strength of the insulating frame 52 is improved.

  As described above, in the vacuum circuit breaker according to the present invention, the horizontally disposed vacuum valve 46 is covered from the left and right by the two symmetrical halves of the insulating frame 52, the upper and lower sides of the vacuum valve 46 and the inner periphery of the insulating frame 52. Since there is a gap between the vacuum valve 46 and the outer periphery of the vacuum valve 46, even when a heat source is disposed below the vacuum valve 46, or when heat is generated by the movable conductor 44, the fixed conductor 48, the vacuum valve 46, etc. When the heated insulating gas flows upward in the two insulating frames 52, natural convection is easily generated, and the cooling performance is improved.

  In addition, since the notches 53 and 54 are provided in the two sides 52a and 52c of the upper and lower ends of the substantially U-shaped cross section of the insulating frame 52, the movable side conductor 44 and the fixed side conductor 48 are connected to the vacuum valve 46. It can be connected to the main circuit arranged above and below at the shortest distance. Further, a mounting rib 55 for mechanically fixing the movable conductor 44 to the insulating frame 52, a mounting end surface 61 for mechanically fixing the fixed conductor 48, and a mechanism for mechanically fixing the insulating frame 52 to the tank 31. Since the tank mounting portions 59 are provided and the conductors and the tank are integrated with the insulating frame, the mechanical strength can be maintained even if the insulating frame has a notch.

  Further, since the two insulating frames 52 are attached to the movable side conductor 44, the fixed side conductor 48, and the vacuum valve 46 in a preassembled state so as to be fitted from the left and right sides of the vacuum valve 46, the attachment position can be easily adjusted. Improves.

  Further, since the reinforcing ribs 52d are provided on the entire circumference of the sides 52a and 52c of the insulating frame 52 where the notches 53 and 54 are provided, the mechanical strength of the insulating frame 52 can be further improved.

  Further, by providing the through-hole portion 65 in the central side 52b having a substantially U-shaped cross section of the insulating frame, the convection of the insulating gas is more easily generated around the insulating frame 52, and the cooling performance is further improved. be able to.

  As described above, the vacuum circuit breaker according to the present invention has a configuration capable of simultaneously improving the cooling characteristics, assembling property and strength.

43 Vacuum circuit breaker 44 Movable side conductor 46 Vacuum valve 48 Fixed side conductor 51 Insulating case 52 Insulating frame 53, 54 Notch 55 Mounting rib 59 Tank mounting part 61 Mounting end face

Claims (2)

A vacuum valve is horizontally arranged in a tank sealed with an insulating gas, the movable side terminal and the fixed side terminal of the vacuum valve are connected to the movable side conductor and the fixed side conductor, respectively, and the vacuum valve is stored in an insulating case. The insulating case includes two insulating frames, a first insulating frame having a substantially U-shaped cross section and a second insulating frame symmetrical to the first insulating frame, and the two insulating frames are spaced apart from each other. In a vacuum circuit breaker that accommodates the vacuum valve with the substantially U-shaped opening of each cross section facing each other,
A cutout portion for passing the movable-side conductor and the fixed-side conductor is provided on one or both sides of the upper and lower ends of the substantially U-shaped cross section of the two insulating frames, and the cross-section of the two insulating frames is substantially A through hole is provided in the center of the U-shape,
Furthermore, the two insulating frames include
A mounting rib for mechanically fixing the movable conductor with a bolt;
An attachment end face that is fixed mechanically by a bolt by contacting the fixed-side conductor; and
Furthermore, a tank mounting part for mechanically fixing the insulating frame to the tank with a bolt is provided,
The two insulating frames are attached so as to cover the movable side conductor, the fixed side conductor, and the vacuum valve assembled in advance so as to face the opening from the left and right sides,
A vacuum circuit breaker, wherein the movable side conductor, the fixed side conductor, and the tank mounting portion are integrally fixed at three locations. The vacuum circuit breaker according to claim 1, wherein reinforcing ribs are formed over the entire circumference of the upper and lower ends of the two insulating frames.

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