JPH10247532A - Current lead for superconductive device - Google Patents
Current lead for superconductive deviceInfo
- Publication number
- JPH10247532A JPH10247532A JP9049022A JP4902297A JPH10247532A JP H10247532 A JPH10247532 A JP H10247532A JP 9049022 A JP9049022 A JP 9049022A JP 4902297 A JP4902297 A JP 4902297A JP H10247532 A JPH10247532 A JP H10247532A
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- Prior art keywords
- temperature
- conductor
- superconducting
- lead
- temperature superconducting
- Prior art date
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、磁気浮上列車、
磁気共鳴画像診断装置等の超電導装置において、真空断
熱容器に収納され液体ヘリウムに浸漬された超電導コイ
ルに外部電源からの励磁電流を通電する電流リードに関
する。The present invention relates to a magnetic levitation train,
In a superconducting device such as a magnetic resonance diagnostic imaging device, the present invention relates to a current lead for supplying an exciting current from an external power supply to a superconducting coil housed in a vacuum heat insulating container and immersed in liquid helium.
【０００２】[0002]
【従来の技術】超電導装置の超電導コイルは、液体ヘリ
ウム等の極低温冷媒により冷却されることにより超電導
状態を保持するので、通常、極低温の窒素を用いた輻射
シールドや多層断熱層を備えた真空断熱容器中に、液体
ヘリウムに浸漬した状態で収納される。この超電導コイ
ルを励磁するためには、真空断熱容器に電流リードを組
み込み、外部電源と接続して励磁電流を通電する。この
とき、常温部と極低温部とを連結することになるので、
この電流リードを介して極低温部へ侵入する熱が多い
と、高価な液体ヘリウムを大量に消費することになる。
したがって、電流リードは自身による熱侵入により気化
した低温のヘリウムガスを利用して自己冷却され、常温
側からの伝導による熱侵入、および通電に伴うジュール
発熱が極低温部へ侵入するのを極力抑制するように配慮
して構成されている。常温部からの熱侵入を抑えるため
には、電流リードの導体の断面積を小さくすることが有
効であるが、導体の断面積を小さくすると電流リードの
電気抵抗が大きくなるので、ジュール発熱が大きくな
る。従って冷却効果を勘案し、これらのバランスのとれ
た構成とすることが重要である。2. Description of the Related Art A superconducting coil of a superconducting device maintains a superconducting state by being cooled by a cryogenic refrigerant such as liquid helium. Therefore, the superconducting coil is usually provided with a radiation shield using cryogenic nitrogen and a multilayer heat insulating layer. It is stored in a vacuum insulated container while immersed in liquid helium. In order to excite the superconducting coil, a current lead is incorporated in a vacuum insulated container and connected to an external power supply to supply an exciting current. At this time, since the normal temperature part and the extremely low temperature part will be connected,
If much heat enters the cryogenic part through the current lead, a large amount of expensive liquid helium will be consumed.
Therefore, the current lead is self-cooled by using the low-temperature helium gas vaporized by the heat penetration by itself, minimizing the heat penetration due to conduction from the room temperature side and the Joule heat generated by energization entering the cryogenic part as much as possible. It is configured with consideration for. It is effective to reduce the cross-sectional area of the conductor of the current lead in order to suppress heat intrusion from the room temperature part.However, if the cross-sectional area of the conductor is reduced, the electric resistance of the current lead increases, so that Joule heat increases. Become. Therefore, it is important to provide a balanced configuration in consideration of the cooling effect.
【０００３】電流リードの導体には、一般に、銅あるい
は銅合金等の良電導体の金属が使用されてきたが、高温
超電導体が発見されるとともに、その極めて高い臨界温
度（超電導状態を保持できる上限の温度）を有効に活用
すれば、低温部分でのジュール発熱がゼロとなること、
熱伝導率が銅の１／１００と小さく熱侵入量を抑制でき
ることが期待され、高温超電導体を用いた電流リードの
開発がおこなわれている。[0003] In general, metals of good conductors such as copper or copper alloy have been used as conductors of current leads. However, with the discovery of high-temperature superconductors, their extremely high critical temperature (the superconducting state can be maintained). Effective use of the upper temperature limit) will result in zero Joule heating in low temperature areas,
It is expected that the thermal conductivity is as small as 1/100 of copper and the amount of heat penetration can be suppressed, and current leads using high-temperature superconductors are being developed.
【０００４】図６は、超電導コイルに接続された従来の
超電導装置用電流リードを簡素化して示した基本構成図
である。図６において、電流リードは、一端に常温端子
１を組み込んだ常温側リード２と、一端に低温端子３を
組み込んだ低温側リード４とから成り、取り付けフラン
ジ７によって真空断熱容器８に取り付けられている。常
温端子１には図示しない外部電源からの接続導体が接続
され、低温端子３には真空断熱容器８の内部に収納され
た液体ヘリウム５０に浸漬、冷却される超電導コイル５
が、低温接続導体６を介して接続されている。電流リー
ドからの熱侵入により液体ヘリウム５０が蒸発して生じ
た低温のヘリウムガス５１は、ヘリウムガス入口９より
電流リード内に入り、導体部を冷却したのちヘリウムガ
ス出口１０より外部に排出される。FIG. 6 is a basic configuration diagram showing a simplified current lead for a conventional superconducting device connected to a superconducting coil. In FIG. 6, the current lead is composed of a normal temperature side lead 2 having a normal temperature terminal 1 incorporated at one end and a low temperature side lead 4 having a low temperature terminal 3 incorporated at one end. I have. A connection conductor from an external power supply (not shown) is connected to the room temperature terminal 1, and a superconducting coil 5 immersed and cooled in liquid helium 50 housed in a vacuum insulated container 8 is connected to the low temperature terminal 3.
Are connected via the low-temperature connection conductor 6. The low-temperature helium gas 51 generated by evaporating the liquid helium 50 due to heat intrusion from the current lead enters the current lead through the helium gas inlet 9, cools the conductor, and is then discharged out of the helium gas outlet 10. .
【０００５】図７は、図６の電流リードの常温側リード
２の横断面図である。図７において、常温側リードは円
形断面を持った多数本の常電導導体１１を円筒状の外筒
１２の内部に組み込んで構成されており、内部の空間は
低温のヘリウムガス５１の流路となっている。通常、常
電導導体１１は銅あるいは銅合金等の良電導体の金属で
構成している。FIG. 7 is a cross-sectional view of the room temperature side lead 2 of the current lead of FIG. In FIG. 7, the normal temperature side lead is configured by incorporating a large number of normal conductors 11 having a circular cross section inside a cylindrical outer cylinder 12, and the internal space is provided with a flow path of a low-temperature helium gas 51. Has become. Normally, the normal conductor 11 is made of a good conductor metal such as copper or a copper alloy.
【０００６】図８は、図６の電流リードの低温側リード
４の横断面図である。図８において、一本の円形断面の
高温超電導導体１４が外筒１３の内部に収納されてお
り、高温超電導導体１４の外周部に低温のヘリウムガス
５１を流して冷却する構成としている。図９は、図６の
電流リードの低温側リード４の縦断面図である。図９に
おいて、高温超電導導体１４の一端は、多数の常電導導
体１１が電気的に接続された良導電性導体からなる中間
接続片１５に半田付け等により電気的、機械的に接続さ
れており、他端は低温端子３に同様の方法で接続されて
いる。液体ヘリウムが蒸発して生じた低温のヘリウムガ
ス５１は、低温端子３に設けられたヘリウム入口９より
導入され、高温超電導導体１４を冷却して超電導状態を
保持するとともに、さらに中間接続片１５に設けられた
ガス通流孔１６を通って常温側リード２の内部へと流
れ、常電導導体１１を冷却している。FIG. 8 is a cross-sectional view of the low-temperature side lead 4 of the current lead of FIG. In FIG. 8, a single high-temperature superconducting conductor 14 having a circular cross section is housed inside an outer cylinder 13, and a configuration is adopted in which a low-temperature helium gas 51 flows through the outer periphery of the high-temperature superconducting conductor 14 to cool it. FIG. 9 is a longitudinal sectional view of the low-temperature side lead 4 of the current lead of FIG. In FIG. 9, one end of the high-temperature superconducting conductor 14 is electrically and mechanically connected by soldering or the like to an intermediate connecting piece 15 made of a good conductive conductor to which a large number of normal conducting conductors 11 are electrically connected. The other end is connected to the low-temperature terminal 3 in a similar manner. The low-temperature helium gas 51 generated by evaporation of the liquid helium is introduced from the helium inlet 9 provided in the low-temperature terminal 3, cools the high-temperature superconducting conductor 14 to maintain the superconducting state, and furthermore, to the intermediate connecting piece 15. The gas flows into the room-temperature-side lead 2 through the gas flow holes 16 provided therein, and cools the normal conductor 11.
【０００７】このように構成された電流リードにおいて
は、低温側リードに高温超電導導体を用い、蒸発した低
温のヘリウムガスで冷却することにより低温側リードで
のジュール発熱がほとんどゼロとなり、高温超電導導体
を用いない電流リードに比較して、極低温部への熱侵入
量が低減され、その結果液体ヘリウムの消費が低減され
る。In the current lead constructed as described above, a high-temperature superconducting conductor is used for the low-temperature side lead, and cooling with the evaporated low-temperature helium gas causes almost no Joule heat generation in the low-temperature side lead. As compared with a current lead that does not use helium, the amount of heat penetrating into the cryogenic portion is reduced, and as a result, the consumption of liquid helium is reduced.
【０００８】[0008]
【発明が解決しようとする課題】しかしながら、このよ
うに優れた特性を持つ超電導装置用電流リードであって
も、低温側リードに用いられている高温超電導導体の両
端の接続部は、その外周に銀箔等を設置して中間接続片
に半田付けしている。従来のこの方法では、熱サイクル
（運転時の冷却、検査のための昇温）による接続部の劣
化によって発生する発熱が問題であり、結果として運転
中にクエンチ（超電導から常電導への転移）が発生する
場合がある。また通常の運転においても、たとえば液体
ヘリウムの流量の減少等の外的要因によって温度が上昇
しクエンチが生じる場合もある。However, even in the current lead for a superconducting device having such excellent characteristics, the connecting portions at both ends of the high-temperature superconducting conductor used for the low-temperature side lead are formed on the outer periphery. A silver foil or the like is placed and soldered to the intermediate connecting piece. In this conventional method, the heat generated by the deterioration of the connection part due to the heat cycle (cooling during operation, temperature rise for inspection) is a problem, and as a result, quenching (transition from superconductivity to normal conduction) during operation is caused. May occur. Also in normal operation, the temperature may rise and quench may occur due to external factors such as a decrease in the flow rate of liquid helium.
【０００９】高温超電導導体は、超電導状態では電気抵
抗がゼロであるのでジュール発熱はゼロであり、また熱
伝導率も銅の約１／１００と小さく、熱侵入量を抑制す
るには極めて有効である。しかしながら、ひとたび上記
のクエンチが生じて常電導状態に転移すると、電気抵抗
が銅材よりも３〜４桁大きいので多大なジュール発熱を
発生することとなり、また上記のように熱伝導率が極め
て小さいので熱の放散が悪く、高温超電導導体の内部の
局部的な温度上昇が極めて大きくなる。したがって最悪
の場合には、高温超電導導体が焼損し使用不可能となる
恐れがある。これを防止するために、電流をバイパスす
るための保護導体を高温超電導導体に並列に設置する必
要があるが、熱侵入量が増大するために高温超電導導体
を用いる効果が半減してしまう。The high-temperature superconducting conductor has no electric resistance in the superconducting state and therefore has no Joule heat generation, and has a heat conductivity as small as about 1/100 that of copper. is there. However, once the above-mentioned quench occurs and transits to the normal conducting state, the electric resistance is 3 to 4 orders of magnitude higher than that of the copper material, so that a large amount of Joule heat is generated, and the thermal conductivity is extremely low as described above. Therefore, heat dissipation is poor, and the local temperature rise inside the high-temperature superconducting conductor becomes extremely large. Therefore, in the worst case, there is a possibility that the high-temperature superconducting conductor may be burned and become unusable. To prevent this, it is necessary to install a protective conductor for bypassing the current in parallel with the high-temperature superconducting conductor, but the effect of using the high-temperature superconducting conductor is reduced by half because the amount of heat penetration increases.
【００１０】本発明の目的は、高温超電導導体を効率的
に冷却し、侵入熱を低減して安全に通電操作を行うこと
のできる超電導装置用電流リードを提供することにあ
る。An object of the present invention is to provide a current lead for a superconducting device capable of efficiently cooling a high-temperature superconducting conductor, reducing heat intrusion, and performing a safe energizing operation.
【００１１】[0011]
【課題を解決するための手段】上記の課題を解決するた
め、本発明においては、常温側リードと低温側リードと
を備えた電流リードにおいて、前記低温側リードを構成
する高温超電導導体と保護導体とを、ともにスパイラル
形状に構成する。かかる構成としたことにより、従来の
棒状の高温超電導導体を使用した低温側リードに比べて
ヘリウムガスによる冷却性能が向上し、高温超電導導体
にクエンチが発生した場合でも保護導体に電流が分流
し、高温超電導導体の局部的な温度上昇を抑制すること
ができ、また高温超電導導体および保護導体の熱伝導に
おける実質上の長さがいずれも増大するので、常温側リ
ードからの伝導による熱侵入量を低減することができ
る。According to the present invention, there is provided a current lead having a normal temperature side lead and a low temperature side lead, wherein the high temperature superconducting conductor and the protective conductor constituting the low temperature side lead are provided. Are formed in a spiral shape. With such a configuration, the cooling performance by helium gas is improved as compared with the conventional low-temperature side lead using a rod-shaped high-temperature superconductor, and even when a quench occurs in the high-temperature superconductor, current is shunted to the protection conductor, The local temperature rise of the HTS conductor can be suppressed, and the substantial lengths of the HTS conductor and the protection conductor in heat conduction both increase. Can be reduced.
【００１２】また、上記の構成に加えて、高温超電導導
体が保護導体により支持される構成とした。かかる構成
としたことにより、高温超電導導体に作用する電磁力を
保護導体で支持することができる。また、低温側リード
の高温側端部と低温側端部との間の中間部分の少なくと
も１箇所以上で高温超電導導体と保護導体とを相互に熱
的、電気的に結合する構成とした。かかる構成としたこ
とにより、高温超電導導体にクエンチが発生した場合
に、低温側リードの端部だけでなく中間部においても、
高温超電導導体側と保護導体側との間でバイパス電流の
流れる回路が形成される。このように、バイパス電流の
流れる回路の数が増大するので、高温超電導導体にクエ
ンチが発生した場合の安全性がより大きくなる。Further, in addition to the above configuration, the high-temperature superconductor is supported by the protective conductor. With such a configuration, the electromagnetic force acting on the high-temperature superconducting conductor can be supported by the protective conductor. Further, the high-temperature superconducting conductor and the protective conductor are thermally and electrically coupled to each other at at least one or more intermediate portions between the high-temperature side end and the low-temperature side end of the low-temperature side lead. With such a configuration, when a quench occurs in the high-temperature superconducting conductor, not only at the end of the low-temperature side lead but also at the intermediate portion,
A circuit through which a bypass current flows is formed between the high-temperature superconducting conductor side and the protection conductor side. As described above, the number of circuits through which the bypass current flows increases, so that the safety when the quench occurs in the high-temperature superconductor is further increased.
【００１３】また、ともにスパイラル形状とした高温超
電導導体と保護導体とを多並列に配置する構成とした。
また、高温超電導導体をシース型高温超電導線材で構成
し、保護導体をステンレス鋼材で構成し、これらを相互
に熱的、電気的に結合したスパイラル形状の構成とし
た。Further, a high-temperature superconducting conductor and a protective conductor, both having a spiral shape, are arranged in multiple parallel.
Further, the high-temperature superconducting conductor is made of a sheath-type high-temperature superconducting wire, the protective conductor is made of stainless steel, and these are thermally and electrically connected to each other in a spiral configuration.
【００１４】また、上記におけるステンレス鋼材にかえ
て保護導体を磁性材で構成した。また、ともにスパイラ
ル形状とした高温超電導導体と保護導体とのいずれか一
方または両方の断面積を、低温側になるにつれて小さく
した。また、ともにスパイラル形状とした高温超電導導
体と保護導体を半径方向に多重配置する構成とした。The protective conductor is made of a magnetic material instead of the stainless steel material described above. In addition, the cross-sectional area of one or both of the high-temperature superconducting conductor and the protective conductor both having a spiral shape was reduced as the temperature became lower. In addition, a high-temperature superconducting conductor and a protective conductor, both of which have a spiral shape, are multiplexed in the radial direction.
【００１５】[0015]
【発明の実施の形態】図１は、本発明による超電導装置
用電流リードの低温側リードの縦断面図である。図１に
おいて、３６は高温超電導導体部であり、その他の構成
要素は図９の構成要素と同一であるので同一の符号で示
されている。図１が図９と相違する点は、高温超電導導
体部３６の構成が異なる点である。FIG. 1 is a longitudinal sectional view of a low-temperature side lead of a current lead for a superconducting device according to the present invention. In FIG. 1, reference numeral 36 denotes a high-temperature superconducting conductor, and other components are the same as those in FIG. FIG. 1 differs from FIG. 9 in that the configuration of the high-temperature superconductor section 36 is different.
【００１６】図２は、図１の高温超電導導体部３６の１
部を拡大した縦断面図で、第１の実施例を示す図であ
る。図２において、薄板円筒３７の外周に、スパイラル
形状で構成した高温超電導線材３４および保護導体３５
からなる高温超電導導体部３６が支持されている。この
薄板円筒３７は、低熱伝導率の特性を有する材料から成
り、たとえば繊維強化樹脂等で構成して、極低温部への
熱侵入を低減している。高温超電導線材３４（たとえば
ビスマス系、イットリウム系等のセラミックスからな
る）が超電導状態から常電導状態に転移した場合に、電
流が保護導体３５に分流するように、高温超電導線材３
４と保護導体３５は半田付けにより熱的、電気的に結合
してある。この構成により、高温超電導線材３４がクエ
ンチした場合でも、局部的な温度上昇を抑制することが
できる。この場合の保護導体３５はステンレス鋼材で構
成される。FIG. 2 shows one of the high-temperature superconducting conductors 36 shown in FIG.
FIG. 2 is a longitudinal sectional view in which a part is enlarged, and is a diagram showing a first embodiment. In FIG. 2, a high-temperature superconducting wire 34 and a protective conductor 35 formed in a spiral shape are provided on the outer periphery of a thin plate cylinder 37.
Is supported. The thin plate cylinder 37 is made of a material having a low thermal conductivity, and is made of, for example, a fiber reinforced resin to reduce heat penetration into a cryogenic portion. When the high-temperature superconducting wire 34 (for example, made of bismuth-based or yttrium-based ceramics) changes from the superconducting state to the normal conducting state, the high-temperature superconducting wire 3
4 and the protective conductor 35 are thermally and electrically connected by soldering. With this configuration, even when the high-temperature superconducting wire 34 is quenched, a local temperature rise can be suppressed. In this case, the protection conductor 35 is made of a stainless steel material.
【００１７】なお、前記の高温超電導線材３４と保護導
体３５とを熱的、電気的に結合するための半田付けは、
高温超電導線材３４および保護導体３５の長さ方向に沿
って断続的に施してもよく、また、全長にわたって連続
的に施してもよい。この半田付けを長さ方向に沿って断
続的に施す場合は、その半田付け箇所が多いほど、高温
超電導線材３４と保護導体３５との間で形成されるバイ
パス電流の回路の数が多くなるので、高温超電導線材３
４にクエンチが発生した場合の安全性がより大きくな
る。The soldering for thermally and electrically coupling the high-temperature superconducting wire 34 and the protective conductor 35 is as follows.
It may be applied intermittently along the length direction of the high-temperature superconducting wire 34 and the protective conductor 35, or may be applied continuously over the entire length. When this soldering is performed intermittently along the length direction, the more soldering locations, the greater the number of bypass current circuits formed between the high-temperature superconducting wire 34 and the protective conductor 35. , High temperature superconducting wire 3
4 is more secure when quench occurs.
【００１８】図３は、図１の高温超電導導体部３６の１
部を拡大した縦断面図で、第２の実施例を示す図であ
る。図３においては、ＡおよびＢの２つのスパイラル形
状の高温超電導導体部３６を並列に配置したものであ
り、電流の増大と短尺化をはかることができる。図４
は、図１の高温超電導導体部３６の詳細構成を示す説明
図である。図４において、薄板円筒３７に設けたスパイ
ラル状の溝部に保護導体３５および高温超電導線材３４
からなる高温超電導導体部を設置してある。保護導体３
５に設けた凹形状の溝に高温超電導線材３４を挿入し、
高温超電導線材３４と保護導体３５とを半田等により熱
的、電気的に結合する。高温超電導線材３４としては、
高温超電導導体（バルク）４０、または銀や銀合金から
なるシース材４２と高温超電導導体４１とから構成され
るシース型高温超電導線材４３を使用する。この場合の
シース型高温超電導線材４３の断面形状は、多角形、円
形いずれでもよい。FIG. 3 shows one of the high-temperature superconducting conductors 36 shown in FIG.
FIG. 9 is a longitudinal sectional view in which a portion is enlarged, and is a diagram showing a second embodiment. In FIG. 3, two high-temperature superconducting conductor portions A and B having a spiral shape are arranged in parallel, so that the current can be increased and the length can be reduced. FIG.
FIG. 2 is an explanatory diagram showing a detailed configuration of a high-temperature superconducting conductor section 36 in FIG. 1. In FIG. 4, a protection conductor 35 and a high-temperature superconducting wire 34 are provided in a spiral groove provided in a thin plate cylinder 37.
A high-temperature superconducting conductor portion made of Protective conductor 3
5. Insert the high-temperature superconducting wire 34 into the concave groove provided in 5,
The high-temperature superconducting wire 34 and the protection conductor 35 are thermally and electrically connected by soldering or the like. As the high-temperature superconducting wire 34,
A high-temperature superconducting conductor (bulk) 40 or a sheath-type high-temperature superconducting wire 43 composed of a sheath material 42 made of silver or a silver alloy and a high-temperature superconducting conductor 41 is used. In this case, the cross-sectional shape of the sheath-type high-temperature superconducting wire 43 may be either polygonal or circular.
【００１９】さらに図４において、保護導体３５の構成
材料として磁性材を用いる場合もある。磁界の大きい環
境では、超電導導体の臨界電流は低下することが一般的
に知られているので、保護導体３５の構成材料として磁
性材を用いることにより、高温超電導導体部３６に発生
する自己磁界を磁性材でシールドすることができ、他の
導体部への影響を小さく（たとえば図３の導体部Ａ、Ｂ
同士の磁気的影響を抑制）し、磁気の大きさによる高温
超電導線材の臨界電流特性の低下を防止している。ま
た、超電導コイルから発生する磁界による高温超電導線
材の臨界電流特性の低下も防止でき、安定した通電を行
うことができる。In FIG. 4, a magnetic material may be used as a constituent material of the protective conductor 35 in some cases. It is generally known that the critical current of the superconducting conductor decreases in an environment with a large magnetic field. Therefore, by using a magnetic material as a constituent material of the protective conductor 35, the self-magnetic field generated in the high-temperature superconducting conductor portion 36 is reduced. It can be shielded by a magnetic material, and has little effect on other conductors (for example, conductors A and B in FIG. 3).
This suppresses the magnetic influence of each other), thereby preventing the critical current characteristic of the high-temperature superconducting wire from deteriorating due to the magnitude of the magnetism. In addition, it is possible to prevent the critical current characteristic of the high-temperature superconducting wire from deteriorating due to the magnetic field generated from the superconducting coil, and it is possible to perform stable energization.
【００２０】図５は、図１の高温超電導導体部３６の１
部を拡大した縦断面図で、第３の実施例を示す。図５に
おいて、常温側リードに近い側の高温超電導導体部３６
では、高温超電導線材３４を４本設置し、低温端子に近
い側の高温超電導導体部３６では２本として、高温超電
導導体の断面積を小さくしている。この構成とすること
により、断面積一定で構成したものに比べて伝導による
熱侵入を軽減することができる。FIG. 5 shows one of the high-temperature superconducting conductors 36 shown in FIG.
The third embodiment is shown in a longitudinal sectional view in which a portion is enlarged. In FIG. 5, the high-temperature superconducting conductor portion 36 on the side close to the room-temperature side lead is shown.
In this example, four high-temperature superconducting wires 34 are provided, and two high-temperature superconducting conductors 36 near the low-temperature terminal are used to reduce the cross-sectional area of the high-temperature superconducting conductor. With this configuration, it is possible to reduce heat penetration due to conduction as compared with a configuration in which the cross-sectional area is constant.
【００２１】また、図２の高温超電導導体部３６を半径
方向に多重配置することにより、大電流容量に適した構
成とすることもできる。Further, by arranging the high-temperature superconducting conductor portions 36 shown in FIG. 2 in the radial direction in a multiplex manner, a configuration suitable for a large current capacity can be obtained.
【００２２】[0022]
【発明の効果】本発明によれば、常温側リードと低温側
リードとを備えた電流リードにおいて、低温側リードを
構成する高温超電導導体と保護導体とを、ともにスパイ
ラル形状に構成したことにより、従来の棒状の高温超電
導導体を使用した低温側リードに比べてヘリウムガスに
よる冷却性能が向上する。また、クエンチが発生した場
合に高温超電導導体は高電気抵抗となるが、電流は保護
導体に分流して流れるので高温超電導導体の温度上昇を
防止することができる。またスパイラル形状とすること
により高温超電導導体および保護導体の熱伝導における
実質上の長さがいずれも増大するので、伝導による熱侵
入量を従来より低減することができる。According to the present invention, in the current lead including the normal temperature side lead and the low temperature side lead, the high temperature superconductor and the protection conductor constituting the low temperature side lead are both formed in a spiral shape. The cooling performance by helium gas is improved as compared with a low-temperature side lead using a conventional rod-shaped high-temperature superconducting conductor. Further, when the quench occurs, the high-temperature superconducting conductor has a high electric resistance. However, since the current is shunted to the protective conductor and flows, the temperature of the high-temperature superconducting conductor can be prevented from rising. In addition, the spiral shape increases the substantial lengths of the high-temperature superconducting conductor and the protective conductor in heat conduction, so that the amount of heat penetration due to conduction can be reduced as compared with the conventional case.
【００２３】また、上記の構成に加えて、高温超電導導
体が保護導体により支持される構成としたことにより、
高温超電導導体に作用する電磁力を保護導体で支持する
ことができるので、低温側リードの導体部の機械的強度
が向上し、超電導装置用電流リードの大容量化が可能と
なる。また、低温側リードの高温側端部と低温側端部と
の間の中間部分の少なくとも１箇所以上で、高温超電導
導体と保護導体とを相互に熱的、電気的に結合する構成
としたことにより、高温超電導導体にクエンチが発生し
た場合に、低温側リードの端部だけでなく中間部におい
ても、高温超電導導体側と保護導体側との間でバイパス
電流の流れる回路が形成される。このように、バイパス
電流の流れる回路の数が増大するので、高温超電導導体
にクエンチが発生した場合の安全性がより大きくなる。Further, in addition to the above configuration, the high-temperature superconducting conductor is configured to be supported by the protective conductor.
Since the electromagnetic force acting on the high-temperature superconducting conductor can be supported by the protective conductor, the mechanical strength of the conductor of the low-temperature side lead is improved, and the capacity of the current lead for the superconducting device can be increased. The high-temperature superconducting conductor and the protective conductor are thermally and electrically coupled to each other at least at one or more intermediate portions between the high-temperature end and the low-temperature end of the low-temperature lead. Accordingly, when a quench occurs in the high-temperature superconducting conductor, a circuit in which a bypass current flows between the high-temperature superconducting conductor side and the protective conductor side is formed not only at the end of the low-temperature side lead but also at the intermediate part. As described above, the number of circuits through which the bypass current flows increases, so that the safety when the quench occurs in the high-temperature superconductor is further increased.
【００２４】さらに、ともにスパイラル形状の構成とし
た高温超電導導体と保護導体を、多並列に配置する構成
とすることにより、信頼性の向上と電流の大容量化をは
かることができる。またさらに、高温超電導導体がシー
ス型高温超電導線材で構成され、保護導体がステンレス
鋼材で構成され、これらを熱的、電気的に結合してスパ
イラル形状に構成したことにより、クエンチが発生した
場合でもシース材に電流が分流して、局部的な温度上昇
を抑制することができる。このステンレス鋼材の熱伝導
率は銅の数十分の１と小さく、熱の伝導距離（長さ）も
あるので、極低温部への熱侵入量は小さく問題とはなら
ない。Further, by employing a configuration in which the high-temperature superconducting conductor and the protective conductor, both of which have a spiral configuration, are arranged in multiple parallel, it is possible to improve the reliability and increase the current capacity. Furthermore, even when a quench occurs, the high-temperature superconducting conductor is made of a sheath-type high-temperature superconducting wire, the protective conductor is made of stainless steel, and these are thermally and electrically connected to form a spiral shape. An electric current is shunted to the sheath material, so that a local temperature rise can be suppressed. Since the thermal conductivity of this stainless steel material is as small as several tenths of copper and there is also a heat conduction distance (length), the amount of heat penetrating into the cryogenic portion is small and poses no problem.
【００２５】またさらに、保護導体を磁性材で構成した
ことにより、超電導コイルから発生する磁界の影響、お
よび多並列に配置した場合に発生する磁界の他の導体部
への影響を低減し、高温超電導導体の臨界電流特性の低
下を防止できる。またさらに、ともにスパイラル形状の
構成とした高温超電導導体と保護導体とのいずれか一方
または両方の断面積を低温側で小さくすることにより、
極低温部への熱侵入量を低減することができる。高温超
電導導体の臨界電流は温度が低いほど大きくなるので、
温度分布より低温側の高温超電導導体の断面積を適切に
選定することにより、極低温部への熱侵入量を低減する
ことができ、安全性および信頼性の向上をはかることが
できる。Further, by forming the protective conductor from a magnetic material, the influence of the magnetic field generated from the superconducting coil and the influence of the magnetic field generated when the coils are arranged in multiple parallel on other conductors can be reduced. The critical current characteristics of the superconducting conductor can be prevented from lowering. Further, by reducing the cross-sectional area of one or both of the high-temperature superconducting conductor and the protective conductor both having a spiral configuration on the low-temperature side,
The amount of heat that enters the cryogenic portion can be reduced. Since the critical current of a high-temperature superconducting conductor increases as the temperature decreases,
By appropriately selecting the cross-sectional area of the high-temperature superconducting conductor on the lower temperature side than the temperature distribution, it is possible to reduce the amount of heat penetrating into the cryogenic part, thereby improving safety and reliability.
【００２６】またさらに、ともにスパイラル形状の構成
とした高温超電導導体と保護導体とを半径方向に多重配
置することにより、大電流容量に適した構成とすること
もできる。Further, by arranging the high-temperature superconducting conductor and the protective conductor, both of which have a spiral configuration, in the radial direction, a configuration suitable for a large current capacity can be obtained.
【図１】本発明による超電導装置用電流リードの低温側
リードの縦断面図。FIG. 1 is a longitudinal sectional view of a low-temperature side lead of a current lead for a superconducting device according to the present invention.
【図２】図１の高温超電導導体部の１部を拡大した縦断
面図で、第１の実施例を示す図。FIG. 2 is an enlarged longitudinal sectional view of a part of the high-temperature superconducting conductor of FIG. 1, showing the first embodiment.
【図３】図１の高温超電導導体部の１部を拡大した縦断
面図で、第２の実施例を示す図。FIG. 3 is an enlarged longitudinal sectional view of a part of the high-temperature superconducting conductor of FIG. 1, showing a second embodiment.
【図４】図１の高温超電導導体部の詳細構成を示す説明
図。FIG. 4 is an explanatory view showing a detailed configuration of a high-temperature superconducting conductor section in FIG. 1;
【図５】図１の高温超電導導体部の１部を拡大した縦断
面図で、第３の実施例を示す図。FIG. 5 is an enlarged longitudinal sectional view of a part of the high-temperature superconducting conductor shown in FIG. 1, showing a third embodiment.
【図６】従来の超電導装置用電流リードを簡素化して示
した基本構成図。FIG. 6 is a basic configuration diagram showing a simplified current lead for a conventional superconducting device.
【図７】図６の電流リードの常温側リードの横断面図。FIG. 7 is a cross-sectional view of the room-temperature side lead of the current lead of FIG. 6;
【図８】図６の電流リードの低温側リードの横断面図。FIG. 8 is a cross-sectional view of a low-temperature side lead of the current lead of FIG. 6;
【図９】図６の電流リードの低温側リードの縦断面図。FIG. 9 is a longitudinal sectional view of a low-temperature side lead of the current lead of FIG. 6;
１…常温端子、２…常温側リード、３…低温端子、４…
低温側リード、５…超電導コイル、６…低温接続導体、
７…取り付けフランジ、８…真空断熱容器、９…ヘリウ
ムガス入口、１０…ヘリウムガス出口、１１…常電導導
体、１２…外筒、１３…外筒、１５…中間接続片、１６
…ガス通流孔、３４…高温超電導線材、３５…保護導
体、３６…高温超電導導体部、３７…薄板円筒、４０…
高温超電導導体（バルク）、４１…高温超電導導体、４
２…シース材、４３…シース型高温超電導線材、５０…
液体ヘリウム、５１…ヘリウムガス。1 ... room temperature terminal, 2 ... room temperature lead, 3 ... low temperature terminal, 4 ...
Low-temperature side lead, 5: superconducting coil, 6: low-temperature connection conductor,
7 Mounting flange, 8 Vacuum insulated container, 9 Helium gas inlet, 10 Helium gas outlet, 11 Normal conductor, 12 Outer cylinder, 13 Outer cylinder, 15 Intermediate connecting piece, 16
... gas flow holes, 34 ... high temperature superconducting wire, 35 ... protective conductor, 36 ... high temperature superconducting conductor, 37 ... thin plate cylinder, 40 ...
High-temperature superconducting conductor (bulk), 41 high-temperature superconducting conductor, 4
2 ... sheath material, 43 ... sheath type high temperature superconducting wire, 50 ...
Liquid helium, 51 ... helium gas.
Claims (8)
に浸漬された超電導コイルに外部電源からの励磁電流を
通電する超電導装置用電流リードにおいて、該電流リー
ドは常温側リードと低温側リードとを備え、前記低温側
リードを構成する高温超電導導体と保護導体とがともに
スパイラル形状に構成されていることを特徴とする超電
導装置用電流リード。1. A current lead for a superconducting device for applying an exciting current from an external power supply to a superconducting coil immersed in liquid helium filled in a vacuum insulated container, wherein the current lead comprises a normal temperature side lead and a low temperature side lead. A current lead for a superconducting device, wherein both the high-temperature superconducting conductor and the protective conductor constituting the low-temperature side lead are formed in a spiral shape.
てなることを特徴とする請求項１に記載の超電導装置用
電流リード。2. The current lead for a superconducting device according to claim 1, wherein the high-temperature superconducting conductor is supported by a protective conductor.
の間の中間部分の少なくとも１箇所以上で高温超電導導
体と保護導体とを相互に熱的、電気的に結合したことを
特徴とする請求項１または２に記載の超電導装置用電流
リード。3. The high-temperature superconducting conductor and the protective conductor are thermally and electrically coupled to each other at at least one or more intermediate portions between the high-temperature end and the low-temperature end of the low-temperature lead. The current lead for a superconducting device according to claim 1 or 2, wherein:
配置する構成としたことを特徴とする請求項１ないし３
に記載の超電導装置用電流リード。4. A high-temperature superconducting conductor and a protective conductor are arranged in multi-parallel with each other.
4. A current lead for a superconducting device according to claim 1.
から成り、保護導体はステンレス鋼材から成り、これら
を相互に熱的、電気的に結合したことを特徴とする請求
項１ないし４に記載の超電導装置用電流リード。5. The high-temperature superconducting conductor according to claim 1, wherein the high-temperature superconducting conductor is made of a sheath-type high-temperature superconducting wire, and the protective conductor is made of stainless steel, and these are thermally and electrically connected to each other. Current lead for superconducting device.
から成り、保護導体は磁性材から成り、これらを相互に
熱的、電気的に結合したことを特徴とする請求項１ない
し４に記載の超電導装置用電流リード。6. The high-temperature superconducting conductor according to claim 1, wherein the high-temperature superconducting conductor is made of a sheath-type high-temperature superconducting wire, and the protective conductor is made of a magnetic material, and these are thermally and electrically connected to each other. Current lead for superconducting device.
一方または両方の断面積を、低温側になるにつれて小さ
くしたことを特徴とする請求項１ないし６に記載の超電
導装置用電流リード。7. The current lead for a superconducting device according to claim 1, wherein the cross-sectional area of one or both of the high-temperature superconducting conductor and the protective conductor decreases as the temperature decreases.
に多重配置する構成としたことを特徴とする請求項１な
いし７に記載の超電導装置用電流リード。8. A current lead for a superconducting device according to claim 1, wherein a high-temperature superconducting conductor and a protective conductor are arranged in a multiplex manner in the radial direction.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9049022A JPH10247532A (en) | 1997-03-04 | 1997-03-04 | Current lead for superconductive device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9049022A JPH10247532A (en) | 1997-03-04 | 1997-03-04 | Current lead for superconductive device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH10247532A true JPH10247532A (en) | 1998-09-14 |
Family
ID=12819500
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9049022A Pending JPH10247532A (en) | 1997-03-04 | 1997-03-04 | Current lead for superconductive device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH10247532A (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1406272A1 (en) * | 2002-10-04 | 2004-04-07 | Nexans | Current supply for superconducting devices |
| EP1408519A1 (en) * | 2002-10-04 | 2004-04-14 | Nexans | Current supply for high temperature superconducting devices |
| JP2008091912A (en) * | 2006-10-02 | 2008-04-17 | General Electric Co <Ge> | High temprature superconducting current lead for superconducting magnet |
| KR101013844B1 (en) | 2008-08-29 | 2011-02-14 | 한국전기연구원 | current lead for variable capacity |
| WO2020035309A1 (en) * | 2018-08-13 | 2020-02-20 | Siemens Aktiengesellschaft | Superconducting current lead |
-
1997
- 1997-03-04 JP JP9049022A patent/JPH10247532A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1406272A1 (en) * | 2002-10-04 | 2004-04-07 | Nexans | Current supply for superconducting devices |
| EP1408519A1 (en) * | 2002-10-04 | 2004-04-14 | Nexans | Current supply for high temperature superconducting devices |
| JP2008091912A (en) * | 2006-10-02 | 2008-04-17 | General Electric Co <Ge> | High temprature superconducting current lead for superconducting magnet |
| EP1918948A1 (en) * | 2006-10-02 | 2008-05-07 | General Electric Company | High temperature superconducting current leads for superconduction magnets |
| KR101013844B1 (en) | 2008-08-29 | 2011-02-14 | 한국전기연구원 | current lead for variable capacity |
| WO2020035309A1 (en) * | 2018-08-13 | 2020-02-20 | Siemens Aktiengesellschaft | Superconducting current lead |
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