JPH03112109A - Gas-filled transformer - Google Patents
Gas-filled transformerInfo
- Publication number
- JPH03112109A JPH03112109A JP24935289A JP24935289A JPH03112109A JP H03112109 A JPH03112109 A JP H03112109A JP 24935289 A JP24935289 A JP 24935289A JP 24935289 A JP24935289 A JP 24935289A JP H03112109 A JPH03112109 A JP H03112109A
- Authority
- JP
- Japan
- Prior art keywords
- tank
- gas
- wall
- cooler
- plate
- 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
- 238000004804 winding Methods 0.000 claims abstract description 19
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 16
- 238000001816 cooling Methods 0.000 claims description 12
- 229910052751 metal Inorganic materials 0.000 abstract description 9
- 239000002184 metal Substances 0.000 abstract description 9
- 238000013021 overheating Methods 0.000 abstract description 7
- 238000005192 partition Methods 0.000 abstract description 4
- 239000003921 oil Substances 0.000 description 6
- 230000004907 flux Effects 0.000 description 5
- 229910000976 Electrical steel Inorganic materials 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000012779 reinforcing material Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 150000003376 silicon Chemical class 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Landscapes
- Transformer Cooling (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ＳＦ６ガスのような絶縁性のガスを絶縁および
冷却の媒体として用いたガス絶縁変圧器に関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a gas insulated transformer using an insulating gas such as SF6 gas as an insulating and cooling medium.
（従来の技術）
油入変圧器に代わる不燃性の変圧器として絶縁油の代り
に不燃性の絶縁ガス（例えばＳＦ６ガス）を冷却および
絶縁の媒体として用いるいわゆるガス絶縁変圧器が数１
０ＭＶＡ程度の容量のものまで実用化されている。この
ようなガス絶縁変圧器においては、油入変圧器に比べ気
体を用いることによる冷却特性の低下は避けられない。(Prior Art) There are several so-called gas insulated transformers that use nonflammable insulating gas (for example, SF6 gas) as a cooling and insulating medium instead of insulating oil as nonflammable transformers that replace oil-immersed transformers.
Even those with a capacity of about 0MVA have been put into practical use. In such a gas insulated transformer, compared to an oil-immersed transformer, the cooling characteristics inevitably deteriorate due to the use of gas.
そこで、鉄心や巻線の内部の冷却方式にはガスを強制的
に流して冷却特性を高めるようにしており、強制対流に
することにより絶縁ガスによっても絶縁油の自然対流並
の冷却特性が得られるようになる。この強制対流を行な
うためには鉄心や巻線に絶縁ガスを送るために送風機が
用いられる。Therefore, in the cooling method inside the iron core and windings, gas is forced to flow to improve the cooling characteristics.By using forced convection, the cooling characteristics of the insulating gas can be compared to the natural convection of insulating oil. You will be able to do it. To perform this forced convection, a blower is used to send insulating gas to the core and windings.
専在のところ３０ＭＶＡ程度まで自然対流冷却方式のガ
ス絶縁変圧器が実用化されているが、自然対流方式の場
合、寸法９重量とも強制対流に比べて大きくなるためＩ
ＯＭＶＡ以上では前記の送風機を用いた強制対流方式が
多い。Gas insulated transformers with natural convection cooling are currently in practical use up to about 30MVA, but natural convection has larger dimensions and weight than forced convection, so
For OMVA and above, the forced convection method using the above-mentioned blower is often used.
従来の強制対流方式のガス絶縁変圧器を第４図および第
５図について説明する。A conventional forced convection type gas insulated transformer will be explained with reference to FIGS. 4 and 5.
図に示すように、鉄心１およびこの鉄心１に巻回された
巻線２をタンク３内に絶縁ガス４とともに収納し、鉄心
１や巻線２内にガスが流れるようにするために仕切板８
で上下に区分されている。As shown in the figure, an iron core 1 and a winding 2 wound around the iron core 1 are stored in a tank 3 together with an insulating gas 4, and a partition plate is installed to allow the gas to flow into the iron core 1 and the winding 2. 8
It is divided into upper and lower parts.
また、タンク３の外部には送風機６を介してガス冷却器
５が接続されている。Further, a gas cooler 5 is connected to the outside of the tank 3 via a blower 6.
ところで、ガス絶縁変圧器において、鉄心１および巻線
２の発熱部を通過して温度上昇した絶縁ガス４は、タン
ク３上部から上部配管を経由して冷却器５に送られこの
内部を通過するとき再び冷却される。冷却器５をでた絶
縁ガス４は下部配管を経てタンク３下部からタンク３内
に戻る。タンク３下部からタンク３内へ送られた絶縁ガ
ス４は鉄心１および巻線２の下部から鉄心１および巻線
２の内部へ導かれ、これらを冷却する。By the way, in a gas insulated transformer, the insulating gas 4 whose temperature has increased after passing through the heat generating parts of the iron core 1 and the winding 2 is sent from the upper part of the tank 3 via the upper piping to the cooler 5 and passes through the inside thereof. When cooled down again. The insulating gas 4 leaving the cooler 5 returns into the tank 3 from the bottom of the tank 3 via the lower piping. The insulating gas 4 sent into the tank 3 from the lower part of the tank 3 is guided from the lower part of the iron core 1 and the winding 2 into the inside of the iron core 1 and the winding 2, and cools them.
送風機６は上部あるいは下部配管の途中に設置される。The blower 6 is installed in the middle of the upper or lower piping.
（図では上部配管に設置されている。）この場合上部あ
るいは下部配管のいずれに取付けても特性上の差はない
が、上部配管に取付ける方がタンクカバー上のスペース
を利用できるので、空間利用の意味では効率的である。(In the figure, it is installed on the upper piping.) In this case, there is no difference in characteristics whether it is installed on the upper or lower piping, but it is better to install it on the upper piping because it can utilize the space above the tank cover. It is efficient in this sense.
また、冷却器５の設置位置は油入変圧器と同様に変圧器
タンク３の両サイドに取付ける場合が多いが、絶縁油に
比べ比重が１／６０程度と小さい絶縁ガス特性を活し、
ガス絶縁変圧器の階上に冷却器を配置する構成も実用化
されている。タンク壁７には後記する理由で磁気シール
ド１５が適当な間隔を置いて取付けられている。１６は
負荷時タップ切換器である。In addition, although the cooler 5 is often installed on both sides of the transformer tank 3 in the same way as an oil-immersed transformer, the cooler 5 is installed on both sides of the transformer tank 3 in the same way as an oil-immersed transformer.
A configuration in which a cooler is placed above a gas-insulated transformer has also been put into practical use. Magnetic shields 15 are attached to the tank wall 7 at appropriate intervals for reasons to be described later. 16 is an on-load tap changer.
（発明が解決しようとする課題）
ところで、このようなガス絶縁変圧器では容量あるいは
インピーダンス電圧が大きくなると、巻線２の洩れ磁束
が増加し、この洩れ磁束が変圧器内の金属構造物やタン
ク３に鎖交すると、渦電流が発生し、金属構造物やタン
ク壁７が加熱される。(Problem to be Solved by the Invention) By the way, in such a gas insulated transformer, as the capacity or impedance voltage increases, the leakage magnetic flux of the winding 2 increases, and this leakage magnetic flux is transmitted to the metal structures inside the transformer and the tank. 3, an eddy current is generated and the metal structure and tank wall 7 are heated.
油入変圧器でも同様の現象が発生して金属構造物やタン
ク壁が加熱されるが、絶縁油の冷却特性がよいためほと
んど問題になることはない。しかし、タンク壁７の過熱
対策としてタンク内壁面に沿ってアルミ製の電磁シール
ド板をはって磁束の集中を避けたり、珪素鋼板の磁気シ
ールド１５によりタンク壁７に入射する磁束量を減らし
て対処している。A similar phenomenon occurs in oil-immersed transformers, causing the metal structures and tank walls to heat up, but this is rarely a problem due to the good cooling properties of insulating oil. However, as a countermeasure against overheating of the tank wall 7, an electromagnetic shield plate made of aluminum is installed along the inner wall surface of the tank to avoid concentration of magnetic flux, and the amount of magnetic flux incident on the tank wall 7 is reduced by using a magnetic shield 15 made of silicon steel plate. I'm dealing with it.
一方、ガス絶縁変圧器では、前述したように絶縁ガスの
冷却特性は自然対流では絶縁油の１１５〜１／１０であ
るため、油入変圧器に比べ小容量。On the other hand, in a gas insulated transformer, as mentioned above, the cooling properties of the insulating gas are 115 to 1/10 that of insulating oil in the case of natural convection, so the capacity is smaller than that of an oil-immersed transformer.
低インピーダンス電圧でもこの問題が顕在化するので、
油入変圧器より相当小さい容量から過熱対策が必要とな
る。しかしながら、このような対策を講することにより
、材料費の高騰や取付作業のための製作工数の大幅な増
加等による変圧器のコストアップが避けられず、また珪
素鋼板製の磁気シールド１５は曲率の小さいタンクには
取付けられないことから、タンクの形状についても制限
をうけるという問題がある。This problem becomes apparent even at low impedance voltages, so
Measures against overheating are required since the capacity is considerably smaller than that of an oil-immersed transformer. However, by taking such measures, it is unavoidable that the cost of the transformer increases due to a sharp rise in material costs and a significant increase in the number of manufacturing steps required for installation work.In addition, the magnetic shield 15 made of silicon steel sheet Since it cannot be installed on small tanks, there is a problem in that there are restrictions on the shape of the tank.
本発明は前記の問題を解決するためになされたもので、
変圧器のタンク壁にシールドを取り付けることなく、タ
ンク壁の過熱を防止し安価で製作の容易な大容量化に適
するガス絶縁変圧器を得ることを目的とするものである
。The present invention was made to solve the above problems,
The object of the present invention is to provide a gas insulated transformer that prevents overheating of the tank wall of the transformer without attaching a shield to the tank wall, is inexpensive, easy to manufacture, and is suitable for increasing capacity.
［発明の構成］
（課題を解決するための手段）
本発明は上記の目的を達成するために、鉄心および巻線
を収納するタンクと、このタンク内に封入された絶縁ガ
スと、この絶縁ガスを冷却する冷却器を有するガス絶縁
変圧器において、前記タンク側壁面の少なくとも一部分
を２重化し、この２重化した内部の間隙内を経由して前
記冷却器からでた絶縁ガスがタンク内へ導かれるように
構成したものである。[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a tank for storing an iron core and a winding, an insulating gas sealed in the tank, and an insulating gas. In a gas insulated transformer having a cooler for cooling, at least a portion of the side wall surface of the tank is doubled, and the insulating gas discharged from the cooler enters the tank through a gap inside the double layer. It is designed to guide you.
（作 用）
本発明によると、過熱が生じ易いタンク壁を２重化し、
その内部に冷却器で冷却された絶縁ガスを強制的に流す
ようにしたので、強制対流により熱伝達率を向上し、絶
縁油の自然対流と同等の熱伝達率とすることができる。(Function) According to the present invention, the tank wall, which is prone to overheating, is doubled,
Since the insulating gas cooled by the cooler is forced to flow inside, the heat transfer coefficient is improved by forced convection, and the heat transfer coefficient can be made equivalent to the natural convection of insulating oil.
仮に、２重化したタンクの間隙を１０ａｎとし、この間
隙中に５ ｍ ／ ｓの流速でＳＦ６ガスを流すと、ガ
ス圧１．２５Ｋｇ／ｃｍ２・ｇで熱伝達率は約８０Ｗ／
ｍ２ ・Ｃとなり、絶縁油の自然対流熱伝達率とほぼ同
様な値となる。If the gap between the duplicated tanks is 10 an and SF6 gas is flowed through this gap at a flow rate of 5 m/s, the heat transfer coefficient will be approximately 80 W/cm at a gas pressure of 1.25 Kg/cm2・g.
m2 ・C, which is almost the same value as the natural convection heat transfer coefficient of insulating oil.
（実施例） 以下、本発明の実施例を図面を参照して説明する。(Example) Embodiments of the present invention will be described below with reference to the drawings.
第１図は本発明の一実施例の縦断面図である。FIG. 1 is a longitudinal sectional view of one embodiment of the present invention.
第１図に示すように、鉄心１およびこの鉄心ｌに巻回さ
れた巻線２をタンク３内に絶縁ガス４とともに収納し、
タンク３内部は絶縁ガス４の入口側と出口側とに差圧を
設け、鉄心１や巻線２内にガスが流れるようにするため
に仕切板８で上下に区分されている。またタンク３の外
部には送風機６を介してガス冷却器５が接続されている
。タンク３の外面側にタンク壁７と例えば１０ｃｍの間
隙をとって金属製の板１０を取付け、この板１０の上部
にガス冷却器５で冷却された絶縁ガス４の取り入れ孔１
１を設け、この取り入れ孔１１から入った絶縁ガスはタ
ンク壁７と前記板１０との間の間隙を流れた後、タンク
壁下部開口部１２からタンク３内に入るように構成され
ている。As shown in FIG. 1, an iron core 1 and a winding 2 wound around the iron core 1 are stored in a tank 3 together with an insulating gas 4,
The inside of the tank 3 is divided into upper and lower parts by a partition plate 8 in order to provide a differential pressure between the inlet side and the outlet side of the insulating gas 4 and to allow the gas to flow into the iron core 1 and the windings 2. Further, a gas cooler 5 is connected to the outside of the tank 3 via a blower 6. A metal plate 10 is attached to the outer surface of the tank 3 with a gap of, for example, 10 cm from the tank wall 7, and an intake hole 1 for the insulating gas 4 cooled by the gas cooler 5 is provided in the upper part of this plate 10.
1 is provided, and the insulating gas entering through the intake hole 11 flows through the gap between the tank wall 7 and the plate 10, and then enters the tank 3 through the lower opening 12 of the tank wall.
板１０の取付方法については第２図の平面図および第３
図の一部を断面で示した側面図に示すように、ガス絶縁
変圧器のタンク３には内部に高圧力および真空時に変形
が生じないようにするため金属製の補強材１３が溶接で
固着されている。For details on how to attach the plate 10, see the plan view in Fig. 2 and the plan view in Fig. 3.
As shown in the partially cross-sectional side view of the figure, a metal reinforcing material 13 is welded to the tank 3 of the gas insulated transformer to prevent deformation during high pressure and vacuum conditions. has been done.
この補強材１３に前記の板１０を溶接し、タンクを２重
化する。板１０の上部および下部端とタンク壁７間にも
板材１４を溶接するなどして封じ、上下に絶縁ガス４が
洩れないようにすることは当然である。タンク壁７と板
１０との間隙寸法を変えればこの間隙内の絶縁ガス４の
流速は自由に選べる。The plate 10 described above is welded to this reinforcing material 13 to double the tank. It goes without saying that the upper and lower ends of the plate 10 and the tank wall 7 are also sealed by welding the plate material 14 to prevent the insulating gas 4 from leaking upward or downward. By changing the size of the gap between the tank wall 7 and the plate 10, the flow rate of the insulating gas 4 within this gap can be freely selected.
第２図は３相３脚鉄心に巻線が配置された場合に巻線に
対向するタンク壁７の外側に板１０を取付けた状態を示
している。板１０がないタンク壁部分は内側に負荷時タ
ップと切換器が設置され、巻線とタンク壁との距離が大
きいため、洩れ磁束によるタンク壁の温度上昇が問題に
ならない部分である。FIG. 2 shows a state in which a plate 10 is attached to the outside of the tank wall 7 facing the windings when the windings are arranged on a three-phase, three-leg iron core. The tank wall portion without the plate 10 has the load tap and switching device installed inside, and the distance between the winding and the tank wall is large, so the temperature rise in the tank wall due to leakage magnetic flux is not a problem.
［発明の効果］
以上説明したように、本発明によれば、鉄心および巻線
を収納するタンクと、このタンク内に封入された絶縁ガ
スと、この絶縁ガスを冷却するガス冷却器を有するガス
絶縁変圧器において、タンク外壁面の外側に金属製の板
を配置し、この板とタンク壁との間にガス流路を設ける
ようにしたので、タンク壁の過熱を防止し、安価で製作
容易な大容量化に適したガス絶縁変圧器を得ることがで
きる。[Effects of the Invention] As explained above, according to the present invention, a gas tank having a tank for storing an iron core and a winding, an insulating gas sealed in the tank, and a gas cooler for cooling the insulating gas is provided. In the isolation transformer, a metal plate is placed on the outside of the tank outer wall, and a gas flow path is provided between this plate and the tank wall, which prevents overheating of the tank wall and is inexpensive and easy to manufacture. A gas insulated transformer suitable for increasing capacity can be obtained.
また、タンク内壁面に珪素鋼板を積層した磁気シールド
を取付ける必要がなくなるため、タンクの曲率半径を小
さくでき、最小限の鋼材で強度の高いタンクを製作する
ことができる。Furthermore, since there is no need to attach a magnetic shield made of laminated silicon steel plates to the inner wall of the tank, the radius of curvature of the tank can be reduced, and a highly strong tank can be manufactured using a minimum amount of steel.
さらに、ガス冷却器とタンクとを接続する冷却配管をタ
ンクの上部に取付けるため、タンク下部まで配管を導い
ている従来例に比ベタンクの側面のスペースを点検用の
通路としたり、付属品を設置するなど有効に利用できる
。Furthermore, since the cooling piping that connects the gas cooler and the tank is installed at the top of the tank, the space on the side of the tank can be used as a passageway for inspection and accessories can be installed, compared to the conventional system where the piping is led to the bottom of the tank. It can be used effectively.
第１図は本発明の一実施例の縦断面図、第２図は第１図
のタンク構造を示す平面図、第３図は第２図のＡ−Ａ線
から見たタンク構造の一部を断面で示した側面図、第４
図は従来のガス絶縁変圧器の縦断面図、第５図は第４図
のタンク構造の平面図である。
１・・・鉄心
２・・・巻線
３・・・タンク
４・・・絶縁ガス
５・・・ガス冷却器
６・・・送風機
７・・・タンク壁
８・・・仕切板
９・・・ガス流路
１０．１４・・・板
１１・・・取り入れ孔
１２・・・開口部
１３・・・補強材
１５・・・タンク磁気シールド
１６・・・負荷時タップ切換器
（８７３３）代理人 弁理士 猪 股 祥 晃（ほか
１名）
第
２
図Fig. 1 is a longitudinal sectional view of an embodiment of the present invention, Fig. 2 is a plan view showing the tank structure of Fig. 1, and Fig. 3 is a part of the tank structure seen from line A-A in Fig. 2. A side view showing a cross section, No. 4
The figure is a longitudinal sectional view of a conventional gas insulated transformer, and FIG. 5 is a plan view of the tank structure of FIG. 4. 1... Iron core 2... Winding 3... Tank 4... Insulating gas 5... Gas cooler 6... Blower 7... Tank wall 8... Partition plate 9... Gas flow path 10.14... Plate 11... Intake hole 12... Opening 13... Reinforcement material 15... Tank magnetic shield 16... On-load tap changer (8733) Agent Patent attorney Yoshiaki Inomata (and others)
1 person) Figure 2
Claims (1)
内に封入された絶縁ガスと、この絶縁ガスを冷却する冷
却器を有するガス絶縁変圧器において、前記タンク側壁
面の少なくとも一部分を２重化し、この２重化した内部
の間隙内を経由して前記冷却器からでた絶縁ガスがタン
ク内へ導かれるように構成したことを特徴としたガス絶
縁変圧器。(1) In a gas insulated transformer having a tank for storing an iron core and a winding, an insulating gas sealed in the tank, and a cooler for cooling the insulating gas, at least a portion of the side wall surface of the tank is double layered. A gas insulated transformer characterized in that the insulating gas discharged from the cooler is guided into the tank through the double internal gap.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24935289A JPH03112109A (en) | 1989-09-27 | 1989-09-27 | Gas-filled transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24935289A JPH03112109A (en) | 1989-09-27 | 1989-09-27 | Gas-filled transformer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH03112109A true JPH03112109A (en) | 1991-05-13 |
Family
ID=17191750
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24935289A Pending JPH03112109A (en) | 1989-09-27 | 1989-09-27 | Gas-filled transformer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH03112109A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011082414A (en) * | 2009-10-09 | 2011-04-21 | Toshiba Corp | Gas-insulated transformer |
| JP2013149783A (en) * | 2012-01-19 | 2013-08-01 | Yazaki Corp | Coil unit |
| US20220416522A1 (en) * | 2020-03-17 | 2022-12-29 | Abb Schweiz Ag | Switchgear assembly and switchgear |
-
1989
- 1989-09-27 JP JP24935289A patent/JPH03112109A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2011082414A (en) * | 2009-10-09 | 2011-04-21 | Toshiba Corp | Gas-insulated transformer |
| JP2013149783A (en) * | 2012-01-19 | 2013-08-01 | Yazaki Corp | Coil unit |
| US20220416522A1 (en) * | 2020-03-17 | 2022-12-29 | Abb Schweiz Ag | Switchgear assembly and switchgear |
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