JPH01186605A - Gas insulated induction apparatus - Google Patents
Gas insulated induction apparatusInfo
- Publication number
- JPH01186605A JPH01186605A JP486888A JP486888A JPH01186605A JP H01186605 A JPH01186605 A JP H01186605A JP 486888 A JP486888 A JP 486888A JP 486888 A JP486888 A JP 486888A JP H01186605 A JPH01186605 A JP H01186605A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic shield
- winding
- tank
- gas
- insulation
- 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.)
- Pending
Links
- 230000006698 induction Effects 0.000 title claims abstract description 13
- 230000005291 magnetic effect Effects 0.000 claims abstract description 48
- 238000004804 winding Methods 0.000 claims abstract description 25
- 239000011248 coating agent Substances 0.000 claims description 15
- 238000000576 coating method Methods 0.000 claims description 15
- 239000000843 powder Substances 0.000 claims description 11
- 239000004020 conductor Substances 0.000 claims description 3
- 238000009413 insulation Methods 0.000 abstract description 17
- 239000003973 paint Substances 0.000 abstract description 3
- 238000010433 powder painting Methods 0.000 abstract 3
- 238000010422 painting Methods 0.000 abstract 2
- 239000007789 gas Substances 0.000 description 16
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 7
- 229910052782 aluminium Inorganic materials 0.000 description 7
- 238000010586 diagram Methods 0.000 description 7
- 230000004907 flux Effects 0.000 description 6
- 229910000976 Electrical steel Inorganic materials 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000000354 decomposition reaction Methods 0.000 description 3
- 230000005684 electric field Effects 0.000 description 3
- 239000003822 epoxy resin Substances 0.000 description 3
- 238000009434 installation Methods 0.000 description 3
- 229920000647 polyepoxide Polymers 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- 229910052802 copper Inorganic materials 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 239000003302 ferromagnetic material Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 239000002480 mineral oil Substances 0.000 description 2
- 235000010446 mineral oil Nutrition 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 239000000112 cooling gas Substances 0.000 description 1
- 230000006378 damage Effects 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 230000002040 relaxant effect Effects 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
Landscapes
- Regulation Of General Use Transformers (AREA)
Abstract
Description
【発明の詳細な説明】
［発明の目的］
（産業上の利用分野）
本発明はガス絶縁誘導機器における磁気シールドの改良
に関する。DETAILED DESCRIPTION OF THE INVENTION OBJECTS OF THE INVENTION Field of Industrial Application The present invention relates to improvements in magnetic shielding in gas-insulated induction equipment.
（従来の技術）
従来、大容量の鉱油絶縁誘導機器などでは、漏洩磁束に
よるタンク壁の温度上昇を抑えるために、タンク壁内側
に磁気シールドを取付けるのが一般的である。(Prior Art) Conventionally, in large-capacity mineral oil insulated induction equipment, etc., a magnetic shield is generally attached to the inside of the tank wall in order to suppress the rise in temperature of the tank wall due to leakage magnetic flux.
一方、近年、防災形の不燃性変圧器として需要が高まっ
ているガス絶縁変圧器においては、冷却媒体として用い
ているＳＦ６等のガスの冷却特性が絶縁油に比べて劣る
ため、比較的小容量の機器でも磁気シールドを取付けて
いる。On the other hand, gas insulated transformers, which have been in increasing demand as non-combustible transformers for disaster prevention, have relatively small capacity because the cooling properties of the gas such as SF6 used as a cooling medium are inferior to that of insulating oil. Even some equipment is equipped with magnetic shields.
第３図は、従来のガス絶縁誘導機器への磁気シールドの
取付けを示す概念図である。鉄心１と巻線２がＳＦ８ガ
スを封入したタンク３内に収納されている。タンク３の
内面には、巻線間に生ずる漏洩磁束がタンク３に鎖交し
て渦電流損失を生じタンク３壁に局部的温度上昇が起こ
らぬように、例えば強磁性体よりなる磁気シールド４が
取付けられている。この磁気シールド４は巻線２に対向
するタンク４壁にギャップ５を介して取付けられ、その
ギャップ５内を絶縁ガスが流動することにより冷却され
るようになっている。（実公昭５０−１２８５１号公報
参照）
ところで、磁気シールド４を構成する強磁性体としては
ケイ素鋼板の薄板を用いるのが一般的であるが、このよ
うな場合には、ケイ素鋼板の磁歪振動による騒音を低減
するために、適当なピッチでボルト６等によりタンク３
に固定する必要がある。（特公昭５０−２８１２８号公
報参照）しかしながら、ガス絶縁においては、鉱油絶縁
に比べて絶縁強度の電界依存性が強いため、巻線２に対
向する部分のボルト６の先端を電界緩和形状に成形する
必要があるので製作コストの上昇を招き、しかも巻線２
との間の絶縁距離Ｌａを大きくとる必要があるので機器
の大形化を招く欠点があった。FIG. 3 is a conceptual diagram showing the attachment of a magnetic shield to a conventional gas-insulated induction device. An iron core 1 and a winding 2 are housed in a tank 3 filled with SF8 gas. A magnetic shield 4 made of, for example, a ferromagnetic material is installed on the inner surface of the tank 3 to prevent leakage magnetic flux generated between the windings from interlinking with the tank 3, causing eddy current loss and causing a local temperature rise on the tank 3 wall. is installed. This magnetic shield 4 is attached to the wall of the tank 4 facing the winding 2 through a gap 5, and is cooled by the flow of insulating gas within the gap 5. (Refer to Japanese Utility Model Publication No. 50-12851.) By the way, it is common to use a thin silicon steel plate as the ferromagnetic material constituting the magnetic shield 4. In such a case, magnetostrictive vibration of the silicon steel plate To reduce noise, tighten tank 3 with bolts 6, etc. at an appropriate pitch.
It needs to be fixed. (Refer to Japanese Patent Publication No. 50-28128.) However, in gas insulation, the electric field dependence of the insulation strength is stronger than in mineral oil insulation, so the tip of the bolt 6 facing the winding 2 is formed into an electric field relaxing shape. Since it is necessary to
Since it is necessary to take a large insulation distance La between the two, there is a drawback that the equipment becomes larger.
第４図は、他の従来例を示す概念図である。本例は、磁
気シールド７として食型導性のアルミニウム板または銅
板を用い、侵入する漏洩磁束により誘導電流を誘起し、
この誘導電流による反抗磁束により、タンク壁への磁束
の侵入を防止するようにしたものである。（実公昭５０
−１２６５１号公報参照）
この構成では、ケイ素鋼板のように磁歪振動に対する配
慮をしなくてよいので、図のように巻線２の絶縁に影響
の無いところで、ボルト６等によりタンク３に固定すれ
ばよく、前記の欠点を補うことができる。また、磁気シ
ールド７の電極形状が良くなるので、対巻線絶縁距離Ｌ
ｂをＬａより小さくすることができる。FIG. 4 is a conceptual diagram showing another conventional example. In this example, an eclipse-type conductive aluminum plate or copper plate is used as the magnetic shield 7, and an induced current is induced by the invading leakage magnetic flux.
The repulsive magnetic flux generated by this induced current prevents magnetic flux from entering the tank wall. (Jikko 50s
(Refer to Publication No. 12651) With this configuration, there is no need to take magnetostrictive vibrations into consideration as with silicon steel plates, so it can be fixed to the tank 3 with bolts 6 etc. in a place where the insulation of the winding 2 is not affected as shown in the figure. If possible, the above-mentioned drawbacks can be compensated for. In addition, since the electrode shape of the magnetic shield 7 is improved, the pair-winding insulation distance L
b can be made smaller than La.
（発明が解決しようとする課題）
しかしながら、上記で述べたいずれの例においても、磁
気シールド４，７の取付けによってタンク３寸法が大き
くなり、機器の軽量化、コンパクト化に反する。一般に
、ガス絶縁機器では、ガスの絶縁性を最大限に生かすた
めに、高い圧力でガスを封入している場合が多く、また
、タンク３を構成する補強に必要な剛性は、タンク寸法
の二゛乗に比例して大きくなることから、タンク寸法を
小さくすることが機器構成のうえで非常に重要である。(Problems to be Solved by the Invention) However, in any of the examples described above, the dimensions of the tank 3 increase due to the attachment of the magnetic shields 4 and 7, which is contrary to the desire to make the equipment lighter and more compact. Generally, in gas insulated equipment, gas is often sealed at high pressure in order to make the most of the insulating properties of the gas, and the rigidity required for reinforcing the tank 3 is equal to or smaller than the tank dimensions. Since the size increases in proportion to the power of 2, it is very important to reduce the size of the tank in terms of equipment configuration.
本発明は上記の課題を解決するためになされたもので、
タンク寸法ひいては機器の大きさ、重量を最少限にでき
、しかも信頼性の高い、ガス絶縁誘導機器の磁気シール
ド取付構成を提供するものである。The present invention was made to solve the above problems,
The present invention provides a magnetic shield mounting configuration for gas-insulated induction equipment that can minimize the tank size, and therefore the size and weight of the equipment, and has high reliability.
［発明の構成］
（課題を解決するための手段）
上記目的を達成するために、本発明は巻線と対向するタ
ンク壁内側に、ギャップを介して食型導性の材料よりな
る磁気シールドを配置したガス絶縁誘導機器において、
磁気シールドの少なくとも巻線対向面に絶縁性の粉体塗
装による塗膜を設けたことを特徴とする。[Structure of the Invention] (Means for Solving the Problem) In order to achieve the above object, the present invention provides a magnetic shield made of an edible conductive material through a gap on the inside of the tank wall facing the winding. In the gas insulated induction equipment installed,
The present invention is characterized in that at least the surface of the magnetic shield facing the windings is coated with an insulating powder coating.
（作用）
前述のように、ガス絶縁機器は絶縁強度の強い電界依存
性のために、磁気シールド表面の微少な突起といえども
絶縁の上では重大な弱点になる可能性が高い。そのため
、磁気シールド表面を絶縁性の塗料で平滑に塗装するこ
とによって、絶縁の強度および信頼性を著しく高めるこ
とができる。(Function) As mentioned above, since the insulation strength of gas-insulated equipment is highly dependent on the electric field, even a minute protrusion on the surface of the magnetic shield is likely to become a serious weak point in the insulation. Therefore, by coating the magnetic shield surface smoothly with an insulating paint, the strength and reliability of the insulation can be significantly increased.
中でも粉体塗装は、表面の突起に合せて表面が平滑に仕
上がるように粉状の塗料が付き、しかも厚膜塗装が容易
にできるという優れた特性を有しており最適である。こ
のため上記の手段により、巻線と磁気シールドとの絶縁
距離を小さくすることができ、タンク寸法を最少限にす
ることができる。Among these, powder coating is most suitable because it has the excellent properties of being able to apply a powdery paint so that the surface is finished smoothly according to the protrusions on the surface, and can be easily coated with a thick film. Therefore, by the above means, the insulation distance between the winding and the magnetic shield can be reduced, and the tank size can be minimized.
（実施例）
以下、本発明の一実施例にもとずき、図面を参照して説
明する。(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.
第１図は、本発明によるガス絶縁誘導機器の磁気シール
ド取付は構成を示す概念図である。鉄心１と巻線２がＳ
Ｆ８ガスを封入したタンク３内に収納されている。タン
ク３壁の内面には巻線間に生ずる漏洩磁束がタンク３壁
に鎖交して渦電流損失を生じタンク３壁に局部的゛温度
上昇が起こらぬように、例えばアルミニウム板でできた
磁気シールド８がボルト６によって取付けられている。FIG. 1 is a conceptual diagram showing the configuration of a magnetic shield installation for a gas-insulated induction device according to the present invention. Iron core 1 and winding 2 are S
It is housed in a tank 3 filled with F8 gas. On the inner surface of the tank 3 wall, a magnetic plate made of, for example, an aluminum plate is installed to prevent the leakage magnetic flux generated between the windings from interlinking with the tank 3 wall, causing eddy current loss, and causing a local temperature rise on the tank 3 wall. A shield 8 is attached by bolts 6.
この磁気シールド８は巻線２に対向するタンク３壁にタ
ンク３壁から所定寸法のギャップ５を介して取付けられ
ている。この磁気シールド８の巻線２に対向する面には
、予めエポキシ樹脂系の粉体塗装による塗膜９が施され
ている。巻線２と磁気シールド８との間には、巻線２の
電圧により決まる所定の絶縁距離Ｌｃが保たれている。This magnetic shield 8 is attached to the wall of the tank 3 facing the winding 2 through a gap 5 of a predetermined size from the wall of the tank 3. A coating film 9 made of epoxy resin powder coating is applied in advance to the surface of the magnetic shield 8 facing the winding 2 . A predetermined insulation distance Lc determined by the voltage of the winding 2 is maintained between the winding 2 and the magnetic shield 8.
このように構成したガス絶縁誘導機器では、前に述べた
ような優れた粉体塗装特有の特性ゆえに、アルミニウム
板表面に特別の機械加工を施すこと無しに、電気的にほ
ぼ完全な平面と言えるアース電極が得られ、電位傾度を
高くとることができる。In gas-insulated induction equipment configured in this way, due to the unique characteristics of the excellent powder coating mentioned above, the surface of the aluminum plate can be said to be electrically almost completely flat without any special machining. A ground electrode can be obtained and a high potential gradient can be obtained.
また、エポキシ樹脂は、耐熱性、絶縁性、密着性、耐Ｓ
Ｆ８分解ガス性のいずれにおいても極めて優れた特性が
得られる樹脂の一つであり、高い信頼性が保証できる。In addition, epoxy resin has heat resistance, insulation, adhesion, and S resistance.
It is one of the resins that can provide extremely excellent characteristics in both F8 decomposition gas properties, and high reliability can be guaranteed.
こめため絶縁距離Ｌｃ、すなわちタンク寸法を最少限に
でき、軽量、コンパクトな機器とすることができる。The insulation distance Lc, that is, the tank size, can be minimized, and the device can be lightweight and compact.
さらに、エポキシ樹脂の粉体塗装は、最も普及している
塗装であり、磁気シールド８をタンク３から自由に取外
して単板の状態で塗装を施すことができ、従ってコスト
の面でも有利となる。また、万一、巻線２から磁気シー
ルド８への地絡事故が起きた場合、アルミニウムの溶融
−５Ｆ６分解ガスとアルミニウム蒸気との反応−ガス状
化合物の生成−タンク内ガス圧力の上昇−タンク破壊と
言うような重大事故につながる危険性があるが、上記の
ように磁気シールド８の表面に粉体塗装による塗膜９が
施されていることによって地絡に対する絶縁性が向上し
、上述の重大事故を防止することができる。Furthermore, epoxy resin powder coating is the most popular type of coating, and the magnetic shield 8 can be freely removed from the tank 3 and coated as a single plate, which is advantageous in terms of cost. . In addition, in the event that a ground fault occurs from the winding 2 to the magnetic shield 8, melting of aluminum - reaction between 5F6 decomposition gas and aluminum vapor - production of gaseous compounds - increase in gas pressure in the tank - tank Although there is a risk of serious accidents such as destruction, the powder coating 9 on the surface of the magnetic shield 8 improves the insulation against ground faults, and the above-mentioned Serious accidents can be prevented.
なお、絶縁上は、粉体塗装の代わりに、絶縁板をあてる
方法も考えられるが、シールドと絶縁板の間にガスギャ
ップができることは避けられない。In terms of insulation, applying an insulating plate instead of powder coating may be considered, but it is inevitable that a gas gap will be created between the shield and the insulating plate.
このギャップは熱的絶縁層となって磁気シールドの放熱
を妨げるので好ましくない。This gap is undesirable because it acts as a thermal insulating layer and impedes heat dissipation from the magnetic shield.
第２図は、本発明の他の実施例を示す概念図である。本
例では、複数枚のアルミニウム板よりなる磁気シールド
１０．１０を、各々の間に冷却用ガスギャップを設けて
配置したものである。この場合粉体塗装置ニーよる塗膜
９は、巻線２に近い磁気シールド１０の巻線対向面のみ
に行えばよい。このようにすると、磁気シールド１０．
１０の冷却効率が良いので、比較的大容量器用の磁気シ
ールドとして最適である。FIG. 2 is a conceptual diagram showing another embodiment of the present invention. In this example, magnetic shields 10.10 made of a plurality of aluminum plates are arranged with a cooling gas gap provided between each magnetic shield. In this case, the coating film 9 by powder coating may be applied only to the surface of the magnetic shield 10 close to the winding 2 that faces the winding. In this way, the magnetic shield 10.
10 has good cooling efficiency, making it ideal as a magnetic shield for relatively large-capacity containers.
なお、以上の説明で磁気シールドの材料としてアルミニ
ウム板を用いたのは、価格、重量、耐ＳＦ６分解ガス性
等の特性が最も優れているからであるが、銅などの他の
良導電性材料を用いてもよいことは勿論である。また、
磁気シールドの巻線対向面のみに粉体塗装による塗膜を
設けたのは、経済性および冷却性を考慮してのことであ
るが、両面に設けても本発明の本質に差異のでるもので
はない。In the above explanation, aluminum plate was used as the material for the magnetic shield because it has the best properties such as price, weight, and resistance to SF6 decomposition gas, but other materials with good conductivity such as copper may also be used. Of course, it is also possible to use Also,
The powder coating was provided only on the surface facing the winding of the magnetic shield in consideration of economic efficiency and cooling efficiency, but even if it is provided on both surfaces, there will be no difference in the essence of the present invention. isn't it.
［発明の効果］
以上述べたように、本発明によればタンク寸法を最少限
にでき、かつ、信頼性も向上でき、さらに製作が簡単で
、取付けも容易な磁気シールド構成が得られ、安価、軽
量、コンパクトで信頼度の高いガス絶縁誘導機器を提供
することができる。[Effects of the Invention] As described above, according to the present invention, it is possible to minimize tank dimensions, improve reliability, and obtain a magnetic shielding structure that is easy to manufacture and install, and is inexpensive. We can provide gas-insulated induction equipment that is lightweight, compact, and highly reliable.
第１図は、本発明によるガス絶縁誘導機器の磁気シール
ド取付は構成を示す概念図、第２図は、本発明の他の実
施例を示す概念図、第３図は、従来のガス絶縁誘導機器
における磁気シールドの取付は構成を示す概念図、第４
図は、他の従来例を示す概念図である。
図中、１は鉄心、２は巻線、３はタンク、６はボルト、
８，１０は食型導性体の磁気シールド、９は粉体塗装に
よる塗膜である。
同 第 子 丸 健第１１１Ａ
第２！１１
Ｅｌ！′
□−１
第３ｍ
罰
／７FIG. 1 is a conceptual diagram showing the configuration of magnetic shield installation for gas insulated induction equipment according to the present invention, FIG. The installation of magnetic shields in equipment is shown in the conceptual diagram showing the configuration, Part 4.
The figure is a conceptual diagram showing another conventional example. In the figure, 1 is the iron core, 2 is the winding, 3 is the tank, 6 is the bolt,
8 and 10 are magnetic shields made of edible conductive material, and 9 is a powder coating film. Ken Maru No. 111A No. 2! 11 El! ' □-1 3rd m penalty/7
Claims (1)
電導性の材料よりなる磁気シールドを配置したガス絶縁
誘導機器において、磁気シールドの少なくとも巻線対向
面に絶縁性の粉体塗装による塗膜を設けたことを特徴と
するガス絶縁誘導機器。In gas-insulated induction equipment in which a magnetic shield made of a highly conductive material is placed on the inside of the tank wall facing the winding through a gap, at least the surface of the magnetic shield facing the winding is coated with an insulating powder coating. A gas insulated induction device characterized by being provided with.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP486888A JPH01186605A (en) | 1988-01-14 | 1988-01-14 | Gas insulated induction apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP486888A JPH01186605A (en) | 1988-01-14 | 1988-01-14 | Gas insulated induction apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01186605A true JPH01186605A (en) | 1989-07-26 |
Family
ID=11595652
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP486888A Pending JPH01186605A (en) | 1988-01-14 | 1988-01-14 | Gas insulated induction apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01186605A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009539243A (en) * | 2006-06-01 | 2009-11-12 | ヒュンダイ ヘビー インダストリーズ カンパニー リミテッド | Transformer outer box burst prevention device |
| JP2012146713A (en) * | 2011-01-07 | 2012-08-02 | Japan Ae Power Systems Corp | Non-magnetic shield with insulator |
| JP2016063100A (en) * | 2014-09-19 | 2016-04-25 | 株式会社日立製作所 | Stationary induction electric unit |
-
1988
- 1988-01-14 JP JP486888A patent/JPH01186605A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009539243A (en) * | 2006-06-01 | 2009-11-12 | ヒュンダイ ヘビー インダストリーズ カンパニー リミテッド | Transformer outer box burst prevention device |
| JP2012146713A (en) * | 2011-01-07 | 2012-08-02 | Japan Ae Power Systems Corp | Non-magnetic shield with insulator |
| JP2016063100A (en) * | 2014-09-19 | 2016-04-25 | 株式会社日立製作所 | Stationary induction electric unit |
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