JPH0562572A - Vacuum circuit breaker - Google Patents
Vacuum circuit breakerInfo
- Publication number
- JPH0562572A JPH0562572A JP22267691A JP22267691A JPH0562572A JP H0562572 A JPH0562572 A JP H0562572A JP 22267691 A JP22267691 A JP 22267691A JP 22267691 A JP22267691 A JP 22267691A JP H0562572 A JPH0562572 A JP H0562572A
- Authority
- JP
- Japan
- Prior art keywords
- insulation
- vacuum valve
- circuit breaker
- boat
- vacuum circuit
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
- H01H33/66—Vacuum switches
- H01H33/666—Operating arrangements
- H01H2033/6665—Details concerning the mounting or supporting of the individual vacuum bottles
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
- H01H33/60—Switches wherein the means for extinguishing or preventing the arc do not include separate means for obtaining or increasing flow of arc-extinguishing fluid
- H01H33/66—Vacuum switches
- H01H33/666—Operating arrangements
Landscapes
- Gas-Insulated Switchgears (AREA)
- High-Tension Arc-Extinguishing Switches Without Spraying Means (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、特に、絶縁ガス中で使
用される真空遮断器に関する。BACKGROUND OF THE INVENTION The present invention relates to a vacuum circuit breaker used especially in an insulating gas.
【０００２】[0002]
【従来の技術】図４は真空遮断器の従来例を示すもので
あり、遮断部として消弧室をなす真空バルブ１０１を支
持固定するために、ボート状絶縁支持物１０３が用いら
れ、その中に真空バルブ１が収納された構成で、例えば
キュービクル形開閉装置に収納されるものである。2. Description of the Related Art FIG. 4 shows a conventional example of a vacuum circuit breaker, in which a boat-shaped insulating support 103 is used to support and fix a vacuum valve 101 which constitutes an arc extinguishing chamber as a breaker. The vacuum valve 1 is housed in the housing, and is housed in, for example, a cubicle type opening / closing device.
【０００３】この真空遮断器においては、真空バルブ１
０１の他に、真空バルブ１０１の可動軸１０５に接続さ
れた可とう導体１０７、下部導体１０９などの高圧充電
部や、上部導体１１１などもボート状絶縁支持物１０３
の中に収納することで、相間や対接地間の絶縁性能が保
たれている。また、ボート状絶縁支持物１０３から突出
した上部導体１１１及び、下部導体１０９には、チュー
リップ形の接続導体１１３などで開閉装置の導体部に接
続され、同様に相間や対接地間の絶縁を保っている。In this vacuum circuit breaker, the vacuum valve 1
01, the flexible conductor 107 connected to the movable shaft 105 of the vacuum valve 101, the high-voltage charging portion such as the lower conductor 109, and the upper conductor 111 are also boat-shaped insulating supports 103.
The insulation performance between phases and ground is maintained by storing it inside the. Further, the upper conductor 111 and the lower conductor 109 protruding from the boat-shaped insulating support 103 are connected to the conductor portion of the switchgear by a tulip-shaped connecting conductor 113 or the like to similarly maintain insulation between phases and ground. ing.
【０００４】したがって、この真空遮断器にあっては、
気中絶縁のために、真空バルブ１０１をボート状絶縁支
持物１０３の中に収納することで、他相の真空バルブと
の間や接地電位との間に絶縁物が介在することになり、
絶縁距離を短縮でき、小形化が可能である。すなわち、
図５に示すように、気中での高圧充電部の電界ストレス
曲線をａとすると、絶縁物のない場合の絶縁寸法Ｓ１に
対して高圧充電部の電界ストレスがＥ１とすれば、絶縁
物が介在する時には、絶縁物の厚さ相当分絶縁距離が短
くなり、絶縁寸法Ｓ２に対して電界ストレスはＥ２に上
昇する。しかし、この電界ストレスの上昇に対し、絶縁
物を介在させた場合には、絶縁物の沿面距離が絶縁に寄
与することで、実質的な絶縁距離の増加につながり、換
言すれば許容電界ストレスの上昇をもたらし、絶縁寸法
Ｓ１における許容電界ストレスＥａ１に対して絶縁寸法
Ｓ２における許容電界ストレスＥａ２としてはＥａ２に
上昇する。そして、電界ストレスＥ１，Ｅ２は夫々の許
容電界ストレスＥａ１，Ｅａ２以下に抑えられている結
果、絶縁物を介在させた場合の方がバーリア効果で寸法
を縮小することができるのである。Therefore, in this vacuum circuit breaker,
By accommodating the vacuum valve 101 in the boat-shaped insulating support 103 for air insulation, the insulation is interposed between the vacuum valve of another phase and the ground potential,
Insulation distance can be shortened and miniaturization is possible. That is,
As shown in FIG. 5, when the electric field stress curve of the high voltage charging section in the air is a, the electric field stress of the high voltage charging section is E1 with respect to the insulation dimension S1 in the absence of the insulating material. When intervening, the insulation distance is reduced by the thickness of the insulator, and the electric field stress rises to E2 with respect to the insulation dimension S2. However, in the case of interposing an insulator against the increase in the electric field stress, the creepage distance of the insulator contributes to the insulation, which leads to a substantial increase in the insulation distance. As a result, the allowable electric field stress Ea1 in the insulating dimension S1 rises to Ea2 in comparison with the allowable electric field stress Ea1 in the insulating dimension S1. The electric field stresses E1 and E2 are suppressed below the allowable electric field stresses Ea1 and Ea2, respectively, and as a result, the size can be reduced by the Barrier effect when an insulator is interposed.
【０００５】[0005]
【発明が解決しようとする課題】ところで、定格電圧が
２４〜８４ｋＶの受電設備においては、最近、設置面積
の縮小化などを図るために、内部に６フッ化硫黄ガス
（以下、「絶縁ガス」という）などを封入した箱体の内
部に、真空遮断器や断路器などの主回路機器を収納し
た、キュービクル形ガス絶縁開閉装置の採用が増えてき
ている。By the way, in power receiving equipment having a rated voltage of 24 to 84 kV, recently, in order to reduce the installation area, etc., sulfur hexafluoride gas (hereinafter referred to as "insulating gas") is used. A cubicle-type gas-insulated switchgear, which houses main circuit equipment such as a vacuum circuit breaker and a disconnector, is increasingly being used inside a box that encloses such components.
【０００６】しかしながら、上述した真空遮断器をその
まま絶縁ガスが封入された開閉装置に適用し、ガス絶縁
の特性を生かそうと、より高電圧に適用すると、気中絶
縁の場合に有効であったバーリア効果が低減し、対接地
間距離や相間寸法の縮小化が難しくなるという問題を生
ずる。すなわち、図５に示すように、ガス中で気中の場
合より高電圧を印加した時の高圧充電部の電界ストレス
曲線をｂとすると、この曲線ｂにおいて、絶縁物のない
場合の絶縁寸法Ｓ１における電界ストレスはＥ１’とな
り、絶縁物の介在する場合の絶縁寸法Ｓ２における電界
ストレスはＥ２’となる。ところが、ガス絶縁の場合、
許容電界ストレスは気中の場合の約３倍であるが、絶縁
物の沿面絶縁に対しては絶縁ガスの効果が顕著には現れ
ないため、許容電界ストレスの上昇が絶対値で気中絶縁
の場合の（Ｅａ２−Ｅａ１）と大差なく、前述のバーリ
ア効果としては比較的小さなものとなる。このため、ガ
ス絶縁の場合、絶縁物のない場合の許容電界ストレスＥ
ｇ１に対し、絶縁物を介在させても許容電界ストレスの
上昇率が低く、Ｅｇ２のようになる結果、絶縁物を介在
させた場合、許容電界ストレスＥｇ２より高圧充電部の
電界ストレスＥ２’の方が高くなり、絶縁破壊を生じ、
対電圧性能が低下してしまうためである。言い替える
と、絶縁ガスの中では、気中の場合の絶縁距離に対して
印加される電圧が高くなるために、真空バルブの上下端
部の金属フランジ部分とボート状形絶縁支持物の間隙の
電界ストレスが高くなり、このため絶縁性能を低下させ
てしまうおそれがあり、ガス絶縁による開閉装置の小形
縮小化に制約が加わることになるのである。本発明は上
記に鑑みてなされたもので、その目的としては、ガス絶
縁による開閉装置の小形縮小化に寄与し得る真空遮断器
を提供することにある。However, if the above-mentioned vacuum circuit breaker is applied as it is to a switchgear in which an insulating gas is filled, and if it is applied to a higher voltage in order to make full use of the characteristics of gas insulation, it is effective in the case of air insulation. The barrier effect is reduced, and it becomes difficult to reduce the distance to ground and the dimension between phases. That is, as shown in FIG. 5, assuming that the electric field stress curve of the high-voltage charging section when a higher voltage is applied than in the case of the air in gas is b, in this curve b, the insulation dimension S1 when there is no insulator is The electric field stress at E is E1 ′, and the electric field stress at the insulation dimension S2 when an insulator is present is E2 ′. However, in the case of gas insulation,
The allowable electric field stress is about three times that in the air, but the effect of insulating gas does not significantly appear on the creeping insulation of insulators. In the case (Ea2-Ea1), there is no great difference, and the above-mentioned Barrier effect is relatively small. Therefore, in the case of gas insulation, the allowable electric field stress E in the absence of insulation is
The increase rate of allowable electric field stress is lower than that of g1 even when an insulator is interposed between them, resulting in Eg2. Higher, causing insulation breakdown,
This is because the withstand voltage performance is deteriorated. In other words, in the insulating gas, the voltage applied to the insulating distance in air is higher, so that the electric field between the metal flanges at the upper and lower ends of the vacuum valve and the boat-shaped insulating support is increased. The stress increases, which may reduce the insulation performance, which imposes restrictions on the downsizing of the switchgear by gas insulation. The present invention has been made in view of the above, and an object thereof is to provide a vacuum circuit breaker that can contribute to downsizing of a switchgear by gas insulation.
【０００７】[0007]
【課題を解決するための手段】上記目的を達成するた
め、絶縁ガスが封入された容器内に設けられ、ボート状
絶縁支持物の中に真空バルブを収納した真空遮断器にお
いて、本発明は前記ボート状絶縁支持物における真空バ
ルブの上下端部の金属フランジと対向する部分に開口部
を設けたことを要旨とする。In order to achieve the above object, a vacuum circuit breaker provided in a container in which an insulating gas is sealed and having a vacuum valve housed in a boat-shaped insulating support is provided. The gist is that an opening is provided in a portion of the boat-shaped insulating support facing the metal flanges at the upper and lower ends of the vacuum valve.
【０００８】[0008]
【作用】本発明に係る真空遮断器にあっては、絶縁ガス
が封入された容器内に設けられたボート状絶縁支持物内
に真空バルブを収納した場合に、真空バルブの高圧充電
部と絶縁物とのすき間を小さくしすぎると、このすき間
部分に電界ストレスが集中して相間絶縁性能が低下する
ことに着目してなされたもので、ボート状絶縁支持物に
おける真空バルブの上下端部の金属フランジと対向する
部分に開口部を設けることで、相間絶縁性能を高圧充電
部同士の耐圧性能によって決まるようにしている。In the vacuum circuit breaker according to the present invention, when the vacuum valve is housed in the boat-shaped insulating support provided in the container in which the insulating gas is sealed, it is insulated from the high-voltage charging section of the vacuum valve. This was done by paying attention to the fact that if the gap with the object is too small, the electric field stress concentrates in this gap and the interphase insulation performance deteriorates. By providing an opening at the portion facing the flange, the interphase insulation performance is determined by the pressure resistance performance of the high voltage charging parts.
【０００９】[0009]
【実施例】以下、図面を用いて本発明の実施例を説明す
る。図１は、本発明の一実施例に係る真空遮断器の構成
を示す図である。Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a configuration of a vacuum circuit breaker according to an embodiment of the present invention.
【００１０】図１において、絶縁ガスが封入された箱体
１にＯリング３を介して絶縁ガス中に気密に取り付けら
れた仕切板５に、ボート状絶縁支持物７を固定し、その
中に、真空バルブ９が収納されている。このボート状絶
縁支持物７には、他相方向に、真空バルブ９の上下端部
の金属フランジ１１，１３の対向する部分に開口部１
５，１７が設けられていると共に、真空バルブ９の可動
軸に接続されている摺動可能な通電導体１９や、上部導
体２１及び下部導体２３が収納されている。また、真空
バルブ９の可動軸２５には、絶縁操作棒２７が接続され
ていて、気密摺動部２９を介して、操作機構３１を用い
て真空バルブ９の主接点の開閉が可能となっている。In FIG. 1, a boat-shaped insulating support 7 is fixed to a partition plate 5 which is hermetically attached to an insulating gas via a O-ring 3 in a box body 1 in which the insulating gas is sealed. The vacuum valve 9 is housed. In the boat-shaped insulating support 7, the opening 1 is formed at the upper and lower end portions of the vacuum valve 9 facing the metal flanges 11 and 13 in the other phase direction.
5 and 17 are provided, and a slidable conducting conductor 19 connected to the movable shaft of the vacuum valve 9, an upper conductor 21 and a lower conductor 23 are housed. Further, an insulating operation rod 27 is connected to the movable shaft 25 of the vacuum valve 9, and the main contact of the vacuum valve 9 can be opened and closed by using the operation mechanism 31 via the airtight sliding portion 29. There is.
【００１１】図２は、図１の真空バルブ９及び、ボート
状絶縁支持物７を上から見た要部平面図である。ボート
状絶縁支持物７の底の部分３３は、高圧充電部から発生
する電荷を蓄える作用をし、そのため対接地間の耐電圧
性能の向上が図られている。また互いに他の相の高圧充
電部同士の相間絶縁に対しては、ボート状絶縁支持物７
の縁部３５が介在するが、高圧充電部の対向する個所に
は、開口部１５が設けられてあり、高圧充電部と開口部
の縁部との間の間隙Ｓ３を高圧充電部の絶縁寸法Ｓ４の
１／２より大きくすることで相間の耐電圧性能の向上が
図られている。すなわち、相間方向の絶縁を、絶縁物を
介さずに高圧充電部同士の対向によって決定されるよう
にすることで、絶縁物を介在させた場合よりも耐電圧性
能を向上させるようにしているのである。FIG. 2 is a plan view of the essential parts of the vacuum valve 9 and the boat-shaped insulating support 7 of FIG. 1 as seen from above. The bottom portion 33 of the boat-shaped insulating support 7 has a function of storing electric charges generated from the high-voltage charging section, so that the withstand voltage performance between the ground is improved. For interphase insulation between the high voltage charging parts of the other phases, the boat-shaped insulation support 7
Although an edge portion 35 of the high voltage charging portion is interposed, an opening portion 15 is provided at an opposite portion of the high voltage charging portion, and a gap S3 between the high voltage charging portion and the edge portion of the opening portion is formed by an insulating dimension By making it larger than 1/2 of S4, the withstand voltage performance between phases is improved. That is, since the insulation in the interphase direction is determined by the high-voltage charging units facing each other without an insulator, the withstand voltage performance is improved as compared with the case where an insulator is interposed. is there.
【００１２】したがって、本実施例に係る真空遮断器に
おいては、各真空バルブの各相の高圧充電部間には開口
部１５，１７によってその絶縁間隙すべてが絶縁ガス中
となるので、従来のボート状絶縁支持物に真空バルブが
収納された真空遮断器に比べて、高圧充電部の電界が緩
和されて絶縁性能を向上させることができる。また本実
施例によれば、真空バルブ９の相間寸法を減らすことが
できるので、外形寸法を減らすことができ、この真空遮
断器が収納されるガス絶縁開閉装置の設置床面積を減ら
すことができる。Therefore, in the vacuum circuit breaker according to the present embodiment, the insulation gap is entirely in the insulating gas due to the openings 15 and 17 between the high-voltage charging portions of the respective phases of the respective vacuum valves, so that the conventional boat As compared with a vacuum circuit breaker in which a vacuum valve is housed in a cylindrical insulating support, the electric field of the high-voltage charging unit is relaxed, and the insulating performance can be improved. Further, according to the present embodiment, since the inter-phase dimension of the vacuum valve 9 can be reduced, the outer dimension can be reduced, and the installation floor area of the gas insulated switchgear in which this vacuum circuit breaker is housed can be reduced. ..
【００１３】図３は、本発明の他の実施例に係る真空遮
断器の構成を示す図である。その特徴としては、ボート
状絶縁支持物３７の開口部３９を一体に構成したことに
あり、このようにすることによって、図１の実施例の効
果に加えてボート状絶縁支持物の制作が容易になるとい
う利点がある。FIG. 3 is a diagram showing the structure of a vacuum circuit breaker according to another embodiment of the present invention. The feature is that the opening 39 of the boat-shaped insulating support 37 is integrally configured, and by doing so, in addition to the effect of the embodiment of FIG. 1, it is easy to manufacture the boat-shaped insulating support. Has the advantage that
【００１４】[0014]
【発明の効果】以上説明したように本発明によれば、ボ
ート状絶縁支持物における真空バルブの上下端部の金属
フランジと対向する部分に開口部を設けることで、ガス
絶縁下の相間絶縁性能を真空バルブの高圧充電部同士の
耐圧性能によって決まるようにして、絶縁物を介在させ
た場合よりも相間絶縁の耐電圧性能を向上させるように
したので、ガス絶縁による開閉装置の小形縮小化に寄与
することができる。As described above, according to the present invention, by providing openings in the upper and lower end portions of the vacuum valve of the boat-shaped insulating support facing the metal flanges, the interphase insulating performance under gas insulation can be improved. Is determined by the withstand voltage performance of the high voltage charging parts of the vacuum valve, and the withstand voltage performance of the interphase insulation is improved compared to the case where an insulator is interposed, so the switchgear can be downsized by gas insulation. Can contribute.
【図１】本発明の一実施例の構成を示す図である。FIG. 1 is a diagram showing a configuration of an exemplary embodiment of the present invention.
【図２】当該一実施例の要部構成を示す図である。FIG. 2 is a diagram showing a configuration of a main part of the embodiment.
【図３】本発明の他の一実施例の構成を示す図である。FIG. 3 is a diagram showing the configuration of another embodiment of the present invention.
【図４】従来例の構成を示す図である。FIG. 4 is a diagram showing a configuration of a conventional example.
【図５】従来技術を説明するための図である。FIG. 5 is a diagram for explaining a conventional technique.
７ ボート状絶縁支持物 ９ 真空バルブ １１ 金属フランジ １３ 金属フランジ １５ 開口部 １７ 開口部 １９ 通電導体 ２１ 上部導体 ２３ 下部導体 ２５ 可動軸 ２７ 絶縁操作棒 ２９ 気密摺動部 ３１ 操作機構 ３７ ボート状絶縁支持物 ３９ 開口部 １０１ 真空バルブ １０３ ボート状絶縁支持物 １０５ 可動軸 １０７ 可とう導体 １０９ 下部導体 １１１ 上部導体 １１３ 接続導体 7 Boat-like Insulating Support 9 Vacuum Valve 11 Metal Flange 13 Metal Flange 15 Opening 17 Opening 19 Energizing Conductor 21 Upper Conductor 23 Lower Conductor 25 Movable Shaft 27 Insulation Operating Rod 29 Airtight Sliding Part 31 Operating Mechanism 37 Boat Insulating Supporting Object 39 Opening 101 Vacuum valve 103 Boat-like insulating support 105 Movable shaft 107 Flexible conductor 109 Lower conductor 111 Upper conductor 113 Connection conductor
Claims (1)
れ、ボート状絶縁支持物の中に真空バルブを収納した真
空遮断器において、前記ボート状絶縁支持物における真
空バルブの上下端部の金属フランジと対向する部分に開
口部を設けたことを特徴とする真空遮断器。1. A vacuum circuit breaker, which is provided in a container in which an insulating gas is sealed, and in which a vacuum valve is housed in a boat-shaped insulating support. A vacuum circuit breaker characterized in that an opening is provided in a portion facing the flange.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22267691A JP2941509B2 (en) | 1991-09-03 | 1991-09-03 | Vacuum circuit breaker |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22267691A JP2941509B2 (en) | 1991-09-03 | 1991-09-03 | Vacuum circuit breaker |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0562572A true JPH0562572A (en) | 1993-03-12 |
| JP2941509B2 JP2941509B2 (en) | 1999-08-25 |
Family
ID=16786182
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22267691A Expired - Fee Related JP2941509B2 (en) | 1991-09-03 | 1991-09-03 | Vacuum circuit breaker |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2941509B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006166651A (en) * | 2004-12-09 | 2006-06-22 | Mitsubishi Electric Corp | Switching device |
| EP2261941A1 (en) * | 2008-04-07 | 2010-12-15 | Mitsubishi Electric Corporation | Vacuum breaker and gas insulated switchgear using the same |
| JP2019192582A (en) * | 2018-04-27 | 2019-10-31 | 株式会社日立産機システム | Opening/closing device |
-
1991
- 1991-09-03 JP JP22267691A patent/JP2941509B2/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006166651A (en) * | 2004-12-09 | 2006-06-22 | Mitsubishi Electric Corp | Switching device |
| JP4606146B2 (en) * | 2004-12-09 | 2011-01-05 | 三菱電機株式会社 | Switchgear |
| EP2261941A1 (en) * | 2008-04-07 | 2010-12-15 | Mitsubishi Electric Corporation | Vacuum breaker and gas insulated switchgear using the same |
| EP2261941A4 (en) * | 2008-04-07 | 2014-01-01 | Mitsubishi Electric Corp | Vacuum breaker and gas insulated switchgear using the same |
| JP2019192582A (en) * | 2018-04-27 | 2019-10-31 | 株式会社日立産機システム | Opening/closing device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2941509B2 (en) | 1999-08-25 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |