JP6175295B2 - Tank type vacuum circuit breaker - Google Patents

Description

  Embodiments of the present invention relate to a tank-type vacuum circuit breaker in which external insulation of a vacuum valve is reinforced and an insulating medium in a tank is an insulating gas suitable for the environment.

  Conventionally, in a tank type vacuum circuit breaker, an insulating gas such as SF6 gas is sealed in a tank at a predetermined pressure to reinforce the external insulation of the vacuum valve. However, in the environment, the SF6 gas must be strictly managed, which makes maintenance and inspection work difficult (for example, see Patent Document 1).

  On the other hand, with the increase in the voltage of the vacuum valve, it is known that the outer periphery is molded with an insulating material such as an epoxy resin to reinforce external insulation. This resin-molded vacuum valve is provided with an interface connecting portion for bringing the insulators into close contact with each other, and an indoor specification power cable and an insulating bus are connected (for example, see Patent Document 2).

  For these reasons, if the vacuum valve is molded with an insulating material to reinforce external insulation and housed in a tank, an insulating gas such as SF6 gas can be dispensed with. However, the main circuit is connected to an indoor power cable or insulated bus, and cannot receive power from an overhead line, which is one of the characteristics of the tank type. For this reason, it has been desired to reinforce the external insulation of the vacuum valve and draw it from the overhead wire.

JP2011-229195A JP 2012-243581 A

  The problem to be solved by the present invention is to provide a tank type vacuum circuit breaker that can reinforce the external insulation of a vacuum valve and enclose an insulating gas suitable for the environment in the tank and draw it from an overhead wire. It is in.

In order to solve the above problems, a tank-type vacuum circuit breaker according to an embodiment includes a tank, a vacuum valve having a pair of contacts provided in the tank, an outer periphery of the vacuum valve, and a fixed-side interface. An insulating layer having a connecting portion and a movable side interface connecting portion; a grounding layer provided on an outer periphery of the insulating layer; a fixed side bushing having an interface connecting portion connected to the fixed side interface connecting portion; and the fixed side A fixed side insulator tube for storing the bushing, a movable side bushing having an interface connection portion connected to the movable side interface connection portion, a movable side insulator tube for storing the movable side bushing, the tank, and the fixed side insulator. tube, wherein an insulating gas sealed in substantially atmospheric pressure to the movable side gavage the stationary bushing, the dielectric constant of the insulating layer of the movable-side bushing, the fixed side gavage movable Characterized by being larger than the outer tube.

Sectional drawing which shows the structure of the tank type vacuum circuit breaker which concerns on Example 1 of this invention. Sectional drawing which shows the structure of the tank type vacuum circuit breaker which concerns on Example 2 of this invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  First, a tank type vacuum circuit breaker according to Embodiment 1 of the present invention will be described with reference to FIG. 1 is a cross-sectional view showing a configuration of a tank-type vacuum circuit breaker according to Embodiment 1 of the present invention.

  As shown in FIG. 1, a vacuum valve 2 having a pair of contacts that can be contacted and separated in the axial direction is provided in a metal cylindrical tank 1. A fixed side electrode 4 having a concave fixed side connection portion 3 is fixed to the fixed side of the vacuum valve 2. On the movable side, a contact 6 that slides with the movable shaft 5 is provided on the inner periphery, and a movable electrode 8 having a concave movable-side connection portion 7 on the outer periphery is fixed.

  An insulating layer 9 formed by molding an epoxy resin is provided around the vacuum valve 2, the fixed side electrode 4, the movable side electrode 8, and the like. The fixed-side connection portion 3 is a tapered fixed-side interface connection portion 10 with an electrode exposed at the center, and the movable-side connection portion 7 is also a tapered movable-side interface connection portion 11 with an electrode exposed at the center. The end of the movable insulating layer 9 is a hollow portion, and an insulating operation rod 12 having one end connected to the end of the movable shaft 5 is provided. The other end passes through a flange 13 that closes one end opening of the tank 1 and is connected to the operation mechanism 14.

  The movable side end of the insulating layer 9 is fixed to the flange 13, and the fixed side is fixed to the inner surface of the tank 1 in the lower part of the figure. On the outer periphery of the insulating layer 9, a ground layer 15 to which a conductive paint is applied is provided in a portion indicated by a dotted line excluding the fixed-side interface connecting portion 10 and the movable-side interface connecting portion 11. The other end opening of the tank 1 is closed by a flange 16.

  A fixed-side central conductor 17 is connected to the fixed-side connecting portion 3 and penetrates through the fixed-side insulating pipe 18. The fixed side insulating pipe 18 is attached to the opening hole in the upper left portion of the tank 1 in an inclined manner. Around the fixed-side central conductor 17, a fixed-side insulating layer 19 molded with epoxy resin is provided, and the fixed-side connecting portion 3 side is a convex fixed-side interface connecting portion 20. It comes to adhere to. Around the fixed-side insulating layer 19, a fixed-side ground layer 21 in which a conductive paint is applied to a portion indicated by a dotted line is provided. In the portion where the fixed-side insulating layer 19 is opposed to the flange portion of the fixed-side insulating pipe 18, the fixed-side insulating layer 19 is formed in an annular shape with a curved cross section, and a fixed-side ground layer 21 is provided on the inner surface (at the end of the fixed-side ground layer 21). Electric field relaxation means). A portion of the fixed side insulating layer 19 in the fixed side insulating pipe 18 is creeping insulation. A fixed-side external electrode 22 connected to the overhead wire is provided at the tip of the fixed-side insulating tube 18.

  A movable side central conductor 23 is connected to the movable side connecting portion 7 and penetrates through the movable side insulating pipe 24. The movable side insulating pipe 24 is attached to the opening hole in the upper right portion of the tank 1 in an inclined manner. A movable insulating layer 25 molded with an epoxy resin is provided around the movable central conductor 23, the movable connecting portion 7 side is a convex movable connecting portion 26, and the movable connecting portion 11 is connected. It comes to adhere to. Around the movable insulating layer 25, there is provided a movable ground layer 27 in which a conductive paint is applied to a portion indicated by a dotted line. In the portion where the movable side ground layer 27 is opposed to the flange portion of the movable side insulating tube 24, the movable side ground layer 27 is formed in an annular shape with a curved cross section, and the movable side ground layer 27 is provided on the inner surface (at the end of the movable side ground layer 27). Electric field relaxation means). The movable-side insulating layer 25 portion in the movable-side insulation tube 24 becomes creeping insulation. At the distal end of the movable side insulation tube 24, a movable side external electrode 28 connected to the overhead wire is provided.

  In the tank 1, any insulating gas suitable for the environment such as dry air, nitrogen gas, and carbon dioxide gas is sealed at a positive pressure of approximately atmospheric pressure. A similar insulating gas is sealed in the cavity that houses the insulating operation rod 12. Note that a through-type current transformer may be provided on the outer periphery of the fixed side insulating pipe 18 and the movable side insulating pipe 24.

  Here, a member composed of the fixed-side center conductor 17, the fixed-side insulating layer 19, the fixed-side interface connecting portion 20, the fixed-side ground layer 21 and the like is defined as a fixed-side bushing having an interface connecting portion. Further, a member composed of the movable-side center conductor 23, the movable-side insulating layer 25, the movable-side interface connection portion 26, the movable-side ground layer 27, and the like is defined as a movable-side bushing having an interface connection portion.

  As a result, the external insulation of the vacuum valve 2 can be reinforced. Further, the fixed-side bushing and the movable-side bushing are accommodated in the fixed-side insulation pipe 18 and the movable-side insulation pipe 24, whereby the drawing from the overhead wire can be performed. In the fixed-side bushing and the movable-side bushing, since the electric field relaxation means is provided in a portion facing the fixed-side insulation tube 18 and the movable-side insulation tube 24, the fixed-side bushing, the movable-side bushing itself, and the fixed-side insulation are provided. The electric field relaxation of the ground side of both the tube 18 and the movable side insulating tube 24 can be performed simultaneously.

  If the dielectric constant of the fixed-side insulating layer 19 and the movable-side insulating layer 25 is made larger than that of the fixed-side insulating tube 18 and the movable-side insulating tube 24, the electric field distribution extending in the outer peripheral direction becomes gentle, and the electric field of the creeping insulating portion is increased. Mitigation can be achieved. The withstand voltage characteristics can be improved even if an insulating gas suitable for an environment having a low dielectric strength is generally enclosed in the stationary side insulating pipe 18 and the movable side insulating pipe 24 at a substantially atmospheric pressure. When the fixed side insulating layer 19 and the movable side insulating layer 25 are made of epoxy resin, the dielectric constant can be 4-6, and when the fixed side insulating tube 18 and the movable side insulating tube 24 are made of polymer, the dielectric constant can be made 2-3.

  Further, when the gaps between the fixed-side insulating layer 19, the movable-side insulating layer 25 and the fixed-side insulating tube 18, and the movable-side insulating tube 24 are larger than the insulating thicknesses of the fixed-side insulating tube 18 and the movable-side insulating tube 24, respectively, An increase in electric field due to a short gap including a minute gap can be prevented.

  Further, the ground-side electric field relaxation means may be set to the ground potential by embedding an annular buried shield in the fixed-side insulating layer 19 and the movable-side insulating layer 25.

  According to the tank-type vacuum circuit breaker of the first embodiment, the insulating layer 9 having the fixed-side interface connecting portion 10 and the movable-side interface connecting portion 11 is provided on the outer periphery of the vacuum valve 2, and the fixed-side insulating pipe 18 and the movable side are provided. Since the fixed-side bushing and the movable-side bushing respectively housed in the insulator tube 24 are connected, the external insulation of the vacuum valve 2 can be reinforced, and the tank 1 is filled with an insulating gas suitable for the environment. In addition, good withstand voltage characteristics can be obtained. Furthermore, the molded vacuum valve 2 can receive power from an overhead wire. Since the tank 1 is a non-pressure vessel, a simple and lightweight structure can be achieved.

  Next, a tank type vacuum circuit breaker according to Embodiment 2 of the present invention will be described with reference to FIG. FIG. 2 is a cross-sectional view showing a configuration of a tank-type vacuum circuit breaker according to Embodiment 2 of the present invention. The second embodiment is different from the first embodiment in that a connecting conductor is provided between the vacuum valve and the insulator tube. In FIG. 2, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  As shown in FIG. 2, the fixed side connecting portion 3 is connected with a bent fixed side connecting conductor 30 and connected to the fixed side central conductor 17. The fixed-side connecting conductor 30 is provided with a fixed-side connecting insulating layer 31 on the outer periphery and a fixed-side connecting ground layer 32 on the outer periphery. Both ends are interface connection portions, and one end is in close contact with the fixed-side interface connection portion 10 and the other end is in close contact with the fixed-side interface connection portion 20. The fixed-side bushing composed of the fixed-side center conductor 17, the fixed-side insulating layer 19, the fixed-side interface connecting portion 20, the fixed-side grounding layer 21, etc. is housed entirely in the fixed-side insulation tube 18. .

  A bent movable side connecting conductor 33 is connected to the movable side connecting portion 7 and is connected to the movable side central conductor 23. The movable connection conductor 33 is provided with a movable connection insulating layer 34 on the outer periphery and a movable connection ground layer 35 on the outer periphery. Both ends are interface connection portions, and one end is in close contact with the movable side interface connection portion 11 and the other end is in close contact with the movable side interface connection portion 26. The movable-side bushing composed of the movable-side center conductor 23, the movable-side insulating layer 25, the movable-side interface connecting portion 26, the movable-side ground layer 27, and the like is entirely housed in the movable-side insulation tube 24. .

  Thereby, in Example 1, although the elongate fixed side center conductor 17 and the movable side center conductor 23 were bent, it can be made into linear form. Since the fixed side connecting conductor 30 and the movable side connecting conductor 33 that are bent are short, the manufacturing is easy and the assemblability can be improved.

  In addition, if a fixed side connection conductor 30 and a movable side connection conductor 33 are used with a wire, and the fixed side connection insulation layer 31 and the movable side connection insulation layer 34 are made of rubber, polyethylene or the like, flexibility can be obtained. Assemblability can be further improved.

  According to the tank type vacuum circuit breaker of the second embodiment, in addition to the effects of the first embodiment, the assemblability can be improved.

  According to the embodiment as described above, the vacuum valve molded with the insulating material is accommodated in the tank, the fixed-side bushing having the interface connection portion and the movable-side bushing are connected, and the main circuit is connected to the outside via the insulator tube. Therefore, the external insulation of the vacuum valve can be reinforced and the overhead wire can be drawn. Moreover, a gas suitable for the environment can be sealed in the tank to form a non-pressure vessel.

  Although several embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

DESCRIPTION OF SYMBOLS 1 Tank 2 Vacuum valve 4 Fixed side electrode 8 Movable side electrode 9 Insulating layer 10, 20 Fixed side interface connection part 11, 26 Movable side interface connection part 17 Fixed side center conductor 18 Fixed side insulator pipe 19 Fixed side insulating layer 23 Movable side Center conductor 24 Movable side insulation tube 25 Movable side insulating layer 30 Fixed side coupling conductor 33 Movable side coupling conductor

Claims (4)

A tank,
A vacuum valve having a pair of contacts provided in the tank;
An insulating layer provided on the outer periphery of the vacuum valve, and having a fixed-side interface connecting portion and a movable-side interface connecting portion;
A grounding layer provided on the outer periphery of the insulating layer;
A fixed-side bushing having an interface connection connected to the fixed-side interface connection;
A fixed side insulator tube for storing the fixed side bushing;
A movable-side bushing having an interface connection portion connected to the movable-side interface connection portion;
A movable side insulator tube that houses the movable side bushing;
The tank, the fixed side insulation pipe, the movable side insulation pipe and an insulating gas sealed at approximately atmospheric pressure ,
A tank-type vacuum circuit breaker characterized in that the dielectric constant of the insulating layer of the fixed-side bushing and the movable-side bushing is larger than that of the fixed-side insulating tube and the movable-side insulating tube .   The electric field relaxation means is provided in the said fixed side bushing and the said movable side bushing in the part which opposes the flange part of the said fixed side insulator pipe and the said movable side insulator pipe. Tank type vacuum circuit breaker.   3. The bent connection conductor is connected to the fixed-side interface connecting portion and the movable-side interface connecting portion, respectively, and connected to the fixed-side bushing and the movable-side bushing. Tank type vacuum circuit breaker.   The tank type vacuum circuit breaker according to any one of claims 1 to 3, wherein the insulating gas is any one of dry air, nitrogen gas, and carbon dioxide gas.

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