JP2527774Y2 - Gas insulated current transformer with protection device - Google Patents
Gas insulated current transformer with protection deviceInfo
- Publication number
- JP2527774Y2 JP2527774Y2 JP5750591U JP5750591U JP2527774Y2 JP 2527774 Y2 JP2527774 Y2 JP 2527774Y2 JP 5750591 U JP5750591 U JP 5750591U JP 5750591 U JP5750591 U JP 5750591U JP 2527774 Y2 JP2527774 Y2 JP 2527774Y2
- Authority
- JP
- Japan
- Prior art keywords
- protection device
- electrode
- current transformer
- primary
- conductor
- 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.)
- Expired - Lifetime
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- Regulation Of General Use Transformers (AREA)
- Transformers For Measuring Instruments (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本考案は、サージ吸収用の保護装
置を備えたガス絶縁変流器に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas-insulated current transformer having a surge absorbing protection device.
【０００２】[0002]
【従来の技術】ＳＦ6 ガス等の絶縁ガスを封入した容器
内に変流器本体を収納したガス絶縁変流器では、落雷時
等に発生するサージ電流による絶縁破壊を防止するため
に、サージ吸収用保護装置が設けられている。2. Description of the Related Art A gas-insulated current transformer in which a current transformer main body is housed in a container filled with an insulating gas such as SF 6 gas is used to prevent a dielectric breakdown due to a surge current generated during a lightning strike or the like. An absorption protection device is provided.
【０００３】図４は従来の保護装置付きガス絶縁変流器
の一例を示したもので、この変流器では、容器１の開口
部を気密に閉じるように取付けられた絶縁スペーサ２を
貫通させて第１の１次導体（Ｋ側導体）３Ｋ及び第２の
１次導体（Ｌ側導体）３Ｌと保護装置取付け用電極５と
を設け、導体３Ｋ，３Ｌに１次コイル６の一端及び他端
を接続している。１次コイル６と鎖交するように配置さ
れた環状の鉄心７に２次コイル８が巻回され、２次コイ
ル８の両端は容器１の側面に設けられた図示しない端子
盤に接続されている。FIG. 4 shows an example of a conventional gas-insulated current transformer with a protection device. In this current transformer, an insulating spacer 2 attached so as to hermetically close an opening of a container 1 is penetrated. To provide a first primary conductor (K-side conductor) 3K, a second primary conductor (L-side conductor) 3L, and a protective device mounting electrode 5, and to the conductors 3K and 3L, one end of a primary coil 6 and other components. The ends are connected. A secondary coil 8 is wound around an annular iron core 7 arranged so as to link with the primary coil 6, and both ends of the secondary coil 8 are connected to a terminal board (not shown) provided on a side surface of the container 1. I have.
【０００４】電極５にサージ吸収用保護装置９´が取付
けられ、該保護装置９´の両電極が１次コイル６の両端
に接続されている。容器１内にはＳＦ6 ガス１０が所定
の圧力で封入されている。A surge absorbing protection device 9 ′ is attached to the electrode 5, and both electrodes of the protection device 9 ′ are connected to both ends of the primary coil 6. An SF 6 gas 10 is sealed in the container 1 at a predetermined pressure.
【０００５】図５ないし図７は上記保護装置９´の構造
を示したもので、これらの図において、１０は酸化亜鉛
等から構成された円板状のサージ吸収素子である。複数
のサージ吸収素子１０，１０，…が積層されて対向配置
された２つの電極１１，１１間に配置され、絶縁材料か
らなる複数のスタッドボルト１２及びナット１３からな
る締め付け手段により電極１１，１１が相互に締め付け
られて、両電極間にサージ吸収素子１０，１０，…の積
層体が保持されている。サージ吸収素子の積層体の両端
と電極１１，１１との間にはそれぞれ鉛板等からなる緩
衝材１４，１４が挿入され、これらの緩衝材により、サ
ージ吸収素子１０に応力の集中が生じるのが防止されて
いる。電極１１，１１は金属ボルト１５により絶縁板１
６に固定され、絶縁板１６は金属ボルト１７により図４
の保護装置取付け用電極５に固定されている。FIGS. 5 to 7 show the structure of the protection device 9 '. In these figures, reference numeral 10 denotes a disc-shaped surge absorbing element made of zinc oxide or the like. A plurality of surge absorbing elements 10, 10,... Are disposed between two electrodes 11, 11 which are stacked and opposed to each other, and are fastened by fastening means including a plurality of stud bolts 12 and nuts 13 made of an insulating material. Are mutually fastened, and a stacked body of the surge absorbing elements 10, 10,... Is held between both electrodes. Buffer members 14, 14 made of a lead plate or the like are inserted between both ends of the stacked body of the surge absorbing element and the electrodes 11, 11, respectively. Has been prevented. The electrodes 11 are connected to the insulating plate 1 by metal bolts 15.
6 and the insulating plate 16 is fixed by metal bolts 17 in FIG.
Is fixed to the protective device mounting electrode 5.
【０００６】上記の変流器においては、落雷等によるサ
ージが進入してＫ導体４及びＬ導体５間に大きな電位差
が生じたときに、サージ吸収素子１０の抵抗値が低くな
るため、保護装置９によりサージ電流が吸収され、サー
ジによる１次コイルの絶縁破壊が防止される。In the above current transformer, when a surge due to a lightning strike enters and a large potential difference is generated between the K conductor 4 and the L conductor 5, the resistance value of the surge absorbing element 10 becomes low. 9, the surge current is absorbed, and the dielectric breakdown of the primary coil due to the surge is prevented.
【０００７】[0007]
【考案が解決しようとする課題】従来の保護装置付きガ
ス絶縁変流器では、保護装置を組み立てるために多数の
ボルトを用いていたため、組立が面倒であった。またの
金属ボルト１５，１７はその頭部が電界を乱す原因にな
るため、多数のボルトを用いると、絶縁の信頼性が低く
なるのを避けられなかった。In the conventional gas-insulated current transformer with a protection device, a large number of bolts are used for assembling the protection device, so that the assembly is troublesome. In addition, since the metal bolts 15 and 17 cause the head to disturb the electric field, using a large number of bolts inevitably lowers the reliability of insulation.
【０００８】本考案の目的は、サージ吸収用保護装置の
構造を簡単にして組立を簡単にするとともに、金属ボル
トの使用を廃して絶縁の信頼性を高めた保護装置付きガ
ス絶縁変流器を提供することにある。An object of the present invention is to provide a gas-insulated current transformer with a protection device which has a simplified structure of a surge absorbing protection device, simplifies assembly, and eliminates the use of metal bolts to enhance insulation reliability. To provide.
【０００９】[0009]
【課題を解決するための手段】本考案は、その実施例を
示す図１に見られるように、絶縁スペーサ２を貫通させ
て設けられた第１の１次導体（Ｋ側導体）３Ｋ及び第２
の１次導体（Ｌ側導体）３Ｌに、１次コイル６の一端及
び他端がそれぞれ接続され、第１の１次導体３Ｋ及び第
２の１次導体３Ｌにサージ吸収用保護装置９が接続され
ている保護装置付きガス絶縁変流器に係わるものであ
る。According to the present invention, as shown in FIG. 1 showing an embodiment of the present invention, a first primary conductor (K-side conductor) 3K and a first primary conductor (K-side conductor) provided through an insulating spacer 2 are provided. 2
One end and the other end of the primary coil 6 are connected to the primary conductor (L side conductor) 3L, respectively, and the surge absorbing protection device 9 is connected to the first primary conductor 3K and the second primary conductor 3L. The present invention relates to a gas-insulated current transformer with a protective device as described above.
【００１０】本考案においては、上記保護装置９が、絶
縁スペーサ２に固定した保護装置取付け用電極２０と、
該電極２０に対向配置されて該電極２０に絶縁ボルトに
より固定されたシールド電極２６と、保護装置取付け用
電極２０とシールド電極２６との間に挟みこまれたサー
ジ吸収素子１０とを備えており、保護装置取付け用電極
２０及びシールド電極２６の電位がそれぞれ第１及び第
２の１次導体３Ｋ及び３Ｌの電位に固定されている。In the present invention, the protection device 9 includes a protection device mounting electrode 20 fixed to the insulating spacer 2,
The shield electrode 26 is disposed opposite to the electrode 20 and is fixed to the electrode 20 by an insulating bolt. The surge absorbing element 10 is sandwiched between the protective device mounting electrode 20 and the shield electrode 26. The potentials of the protection device mounting electrode 20 and the shield electrode 26 are fixed to the potentials of the first and second primary conductors 3K and 3L, respectively.
【００１１】[0011]
【作用】上記のように、保護装置取付け用電極にシール
ド電極を対向配置して、両電極間にサージ吸収素子を挟
み込んだ状態でシールド電極を保護装置取付け用電極に
絶縁ボルトで固定する構造にすると、必要最小限の絶縁
ボルトで保護装置を組み立てることができるため、保護
装置の構造を簡単にしてその組立を容易にすることがで
きる。しかも電界を乱す原因となる金属ボルトを用いる
必要がないため、絶縁の信頼性を向上させることができ
る。As described above, the shield electrode is disposed opposite to the protective device mounting electrode, and the shield electrode is fixed to the protective device mounting electrode with insulating bolts with the surge absorbing element sandwiched between the two electrodes. Then, since the protection device can be assembled with the minimum necessary insulating bolts, the structure of the protection device can be simplified and the assembly can be facilitated. In addition, since it is not necessary to use a metal bolt that causes a disturbance in the electric field, the reliability of insulation can be improved.
【００１２】[0012]
【実施例】図１ないし図３は本考案の一実施例を示した
もので、図１は本考案に係わる保護装置付きガス絶縁変
流器の要部を一部断面して示した正面図、図２及び図３
はそれぞれ同実施例で用いる保護装置を一部断面して示
した正面図及び底面図である。1 to 3 show one embodiment of the present invention. FIG. 1 is a front view showing a main part of a gas insulated current transformer with a protection device according to the present invention in a partially sectional view. , FIGS. 2 and 3
3A and 3B are a front view and a bottom view, respectively, showing a protection device used in the embodiment in partial cross section.
【００１３】図１において、２はエポキシ樹脂からなる
絶縁スペーサで、この絶縁スペーサは図４に示した従来
の変流器と同様に、容器の開口部を気密に閉じるように
取り付けられる。絶縁スペーサ２を貫通させて第１及び
第２の１次導体３Ｋ及び３Ｌが設けられ、これらの１次
導体の間に保護装置取付け用電極２０が設けられてい
る。保護装置取付け用電極２０はその両端面を絶縁スペ
ーサの両面に露出させた状態で絶縁スペーサ内に埋設さ
れ、絶縁スペーサ内で導体２１により第１の１次導体３
Ｋ（Ｋ側導体）に電気的に接続されている。In FIG. 1, reference numeral 2 denotes an insulating spacer made of epoxy resin. This insulating spacer is attached so as to hermetically close the opening of the container, similarly to the conventional current transformer shown in FIG. First and second primary conductors 3K and 3L are provided so as to penetrate the insulating spacer 2, and a protection device mounting electrode 20 is provided between these primary conductors. The protection device mounting electrode 20 is buried in the insulating spacer with both end surfaces exposed on both surfaces of the insulating spacer, and the first primary conductor 3 is formed by the conductor 21 in the insulating spacer.
It is electrically connected to K (K-side conductor).
【００１４】１次コイル６は１ターンないし数ターン巻
回されて、エポキシ樹脂等の絶縁樹脂２２によりモール
ドされるとともに、シールド２３Ｋ及び２３Ｌにより覆
われ、シールド２３Ｋ，２３Ｌの間は絶縁リング２４及
び２５により絶縁されている。１次コイル６の一端及び
他端はそれぞれ１次導体３Ｋ及び３Ｌに接続され、シー
ルド２３Ｋ及び２３Ｌの電位はそれぞれ１次導体３Ｋ及
び３Ｌに固定されている。The primary coil 6 is wound one or several turns and molded with an insulating resin 22 such as an epoxy resin, and is covered with shields 23K and 23L. An insulating ring 24 and a shield are provided between the shields 23K and 23L. 25 for insulation. One end and the other end of the primary coil 6 are connected to the primary conductors 3K and 3L, respectively, and the potentials of the shields 23K and 23L are fixed to the primary conductors 3K and 3L, respectively.
【００１５】保護装置取付け用電極２０に、ほぼカップ
状に形成されたシールド電極２６が対向配置され、電極
２０，２６間に酸化亜鉛からなる複数（図示の例では２
個）のサージ吸収素子１０，１０の積層体が配置されて
いる。サージ吸収素子の積層体と保護装置取付け用電極
２０との間及びサージ吸収素子の積層体とシールド電極
２６との間にはそれぞれ鉛板からなる緩衝材１４，１４
が挿入されている。シールド電極２６は４本の絶縁ボル
ト２７により保護装置取り付け用電極２０に締め付け固
定され、これらのボルト２７の締め付け力により、サー
ジ吸収素子１０，１０がシールド電極２６と保護装置取
付け用電極２０との間に挟み込まれた状態で保持されて
いる。サージ吸収素子の積層体の両端に配置された緩衝
材１４，１４により、サージ吸収素子に応力の集中が生
じて該素子が破損するのが防止されている。A shield electrode 26 formed substantially in a cup shape is disposed opposite to the protective device mounting electrode 20, and a plurality of zinc oxide (in the illustrated example, two electrodes) are formed between the electrodes 20, 26.
) Of the surge absorbing elements 10 are arranged. Buffer members 14 and 14 made of a lead plate are provided between the stacked body of the surge absorbing element and the protection device mounting electrode 20 and between the stacked body of the surge absorbing element and the shield electrode 26, respectively.
Is inserted. The shield electrode 26 is fastened and fixed to the protection device mounting electrode 20 by four insulating bolts 27, and the surge absorbing elements 10, 10 are connected between the shield electrode 26 and the protection device mounting electrode 20 by the tightening force of these bolts 27. It is held in a state sandwiched between. The shock absorbers 14 arranged at both ends of the stacked body of the surge absorbing element prevent the surge absorbing element from being stressed and damaged.
【００１６】各絶縁ボルト２７の頭部２７ａが電界分布
に影響を与えることがないようにするため、シールド電
極２６に設けた凹部内に、各絶縁ボルトの頭部２７ａが
収容されている。シールド電極２６は接続導体２８によ
りＬ側のシールド２３Ｌに電気的に接続され、これによ
りシールド電極２３Ｌの電位が１次導体３Ｌの電位に固
定されている。また保護装置取付け用電極２０の電位は
絶縁スペーサ内に埋設された前述の導体２１を介して１
次導体３Ｋの電位に固定されている。In order to prevent the head 27a of each insulation bolt 27 from affecting the electric field distribution, the head 27a of each insulation bolt is housed in a recess provided in the shield electrode 26. The shield electrode 26 is electrically connected to the L-side shield 23L by a connection conductor 28, whereby the potential of the shield electrode 23L is fixed to the potential of the primary conductor 3L. The potential of the protection device mounting electrode 20 is set to 1 through the above-described conductor 21 embedded in the insulating spacer.
It is fixed to the potential of the next conductor 3K.
【００１７】図１には図示してないが、実際には環状鉄
心にトロイダル状に巻回された２次コイルが設けられ、
該２次コイルの環状鉄心が１次コイル６と鎖交するよう
に配置される。Although not shown in FIG. 1, a secondary coil wound in a toroidal shape on an annular core is actually provided.
The annular core of the secondary coil is arranged so as to link with the primary coil 6.
【００１８】上記実施例の変流器において、落雷等によ
り高周波サージが侵入すると、通常はほとんど電位差が
ない１次導体３Ｋ，３Ｌ間に電位差が生じる。この電位
差はシールド電極２６と保護装置取付け用電極２０との
間にかかるため、サージ吸収素子１０の抵抗値が低下し
て、該サージ吸収素子を通して電流が流れる。これによ
り１次導体６に高いサージ電圧が印加されるのが防止さ
れ、１次コイルの絶縁破壊が防止される。In the current transformer of the above-described embodiment, when a high-frequency surge enters due to a lightning strike or the like, a potential difference is generated between the primary conductors 3K and 3L, which have almost no potential difference. Since this potential difference is applied between the shield electrode 26 and the protection device mounting electrode 20, the resistance value of the surge absorbing element 10 is reduced, and a current flows through the surge absorbing element. This prevents a high surge voltage from being applied to the primary conductor 6 and prevents dielectric breakdown of the primary coil.
【００１９】上記の実施例では、４本の絶縁ボルト２７
を用いてシールド電極２６を保護装置取付け用電極２０
に固定しているが、絶縁ボルトは少なくとも３本設けれ
ば良く、その数は任意である。また上記の実施例ではサ
ージ吸収素子１０として酸化亜鉛からなるものを用いた
が、本考案では他の材料からなるサージ吸収素子を用い
ることを何等妨げない。In the above embodiment, four insulating bolts 27 are used.
To the protective device mounting electrode 20 by using
However, it is sufficient that at least three insulating bolts are provided, and the number thereof is arbitrary. Although the surge absorbing element 10 is made of zinc oxide in the above embodiment, the present invention does not hinder the use of a surge absorbing element made of another material.
【００２０】[0020]
【考案の効果】以上のように、本考案によれば、保護装
置取付け用電極にシールド電極を対向配置して、両電極
間にサージ吸収素子を挟み込んだ状態でシールド電極を
保護装置取付け用電極に絶縁ボルトで固定する構造にし
たので、必要最小限の絶縁ボルトで保護装置を組み立て
ることができ、保護装置の構造を簡単にしてその組立を
容易にすることができる利点がある。また本考案では、
電界を乱す原因となる金属ボルトを用いる必要がないた
め、絶縁の信頼性を向上させることができる利点があ
る。As described above, according to the present invention, according to the present invention, the shield electrode is disposed opposite to the protective device mounting electrode, and the surge absorbing element is sandwiched between both electrodes, and the shield electrode is connected to the protective device mounting electrode. The structure is such that the protection device can be assembled with the minimum necessary number of insulation bolts, and there is an advantage that the structure of the protection device can be simplified and the assembly can be facilitated. In the present invention,
Since it is not necessary to use metal bolts that disturb the electric field, there is an advantage that the reliability of insulation can be improved.
【図１】本考案の実施例の要部を一部断面して示した正
面図である。FIG. 1 is a front view partially showing a main part of an embodiment of the present invention.
【図２】図１の実施例で用いる保護装置を一部断面して
示した正面図である。FIG. 2 is a front view partially showing a protection device used in the embodiment of FIG. 1;
【図３】図１の実施例で用いる保護装置の底面図であ
る。FIG. 3 is a bottom view of the protection device used in the embodiment of FIG.
【図４】従来の保護装置付きガス絶縁変流器の一例の構
造を概略的に示した断面図である。FIG. 4 is a sectional view schematically showing the structure of an example of a conventional gas-insulated current transformer with a protection device.
【図５】図４の変流器で用いている保護装置の底面図で
ある。FIG. 5 is a bottom view of a protection device used in the current transformer of FIG.
【図６】図４の変流器で用いている保護装置の正面図で
ある。FIG. 6 is a front view of a protection device used in the current transformer of FIG.
【図７】図４の変流器で用いている保護装置の側面図で
ある。FIG. 7 is a side view of a protection device used in the current transformer of FIG.
２…絶縁スペーサ、３Ｋ…第１の１次導体、３Ｌ…第２
の１次導体、６…１次コイル、９…サージ吸収用保護装
置、１０…サージ吸収素子、２０…保護装置取付け用電
極、２１…導体、２６…シールド電極、２８…接続導
体。2 ... insulating spacer, 3K ... first primary conductor, 3L ... second
Primary conductor, 6 ... Primary coil, 9 ... Surge absorbing protection device, 10 ... Surge absorbing element, 20 ... Protection device mounting electrode, 21 ... Conductor, 26 ... Shield electrode, 28 ... Connection conductor.
Claims (1)
１及び第２の１次導体に１次コイルの両端が接続され、
前記第１の１次導体及び第２の１次導体にサージ吸収用
保護装置が接続されている保護装置付きガス絶縁変流器
において、 前記保護装置は、 前記絶縁スペーサに埋設して設けた保護装置取付け用電
極と、 前記保護装置取付け用電極に対向配置されて該保護装置
取付け用電極に絶縁ボルトにより固定されたシールド電
極と、 前記保護装置取付け用電極とシールド電極との間に挟み
こまれたサージ吸収素子とを具備し、 前記保護装置取付け用電極及びシールド電極の電位がそ
れぞれ前記第１及び第２の１次導体の電位に固定されて
いることを特徴とする保護装置付きガス絶縁変流器。1. Both ends of a primary coil are connected to first and second primary conductors provided through an insulating spacer,
In a gas-insulated current transformer with a protection device in which a surge absorbing protection device is connected to the first primary conductor and the second primary conductor, the protection device is provided with protection provided by being embedded in the insulating spacer. An electrode for mounting the device, a shield electrode which is arranged opposite to the electrode for mounting the protective device and is fixed to the electrode for mounting the protective device by an insulating bolt; and is sandwiched between the electrode for mounting the protective device and the shield electrode. Wherein the potential of the protective device mounting electrode and the potential of the shield electrode are fixed to the potentials of the first and second primary conductors, respectively. Sink.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5750591U JP2527774Y2 (en) | 1991-07-23 | 1991-07-23 | Gas insulated current transformer with protection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5750591U JP2527774Y2 (en) | 1991-07-23 | 1991-07-23 | Gas insulated current transformer with protection device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0511425U JPH0511425U (en) | 1993-02-12 |
| JP2527774Y2 true JP2527774Y2 (en) | 1997-03-05 |
Family
ID=13057592
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5750591U Expired - Lifetime JP2527774Y2 (en) | 1991-07-23 | 1991-07-23 | Gas insulated current transformer with protection device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2527774Y2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5174344U (en) * | 1974-12-10 | 1976-06-11 | ||
| JPS5176159U (en) * | 1974-12-12 | 1976-06-15 | ||
| JPH10149789A (en) * | 1996-11-18 | 1998-06-02 | Nissin Electric Co Ltd | Ion source device |
| JP6847749B2 (en) * | 2017-04-19 | 2021-03-24 | 株式会社東芝 | coil |
-
1991
- 1991-07-23 JP JP5750591U patent/JP2527774Y2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0511425U (en) | 1993-02-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19961015 |
|
| EXPY | Cancellation because of completion of term |