JP2781838B2 - Excitation method of superconducting magnet - Google Patents
Excitation method of superconducting magnetInfo
- Publication number
- JP2781838B2 JP2781838B2 JP1122017A JP12201789A JP2781838B2 JP 2781838 B2 JP2781838 B2 JP 2781838B2 JP 1122017 A JP1122017 A JP 1122017A JP 12201789 A JP12201789 A JP 12201789A JP 2781838 B2 JP2781838 B2 JP 2781838B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic field
- sheet
- superconducting
- excitation method
- magnetic
- 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 - Fee Related
Links
- 238000000034 method Methods 0.000 title claims description 25
- 230000005284 excitation Effects 0.000 title claims description 13
- 239000002887 superconductor Substances 0.000 claims description 37
- 230000007613 environmental effect Effects 0.000 claims description 29
- 230000004907 flux Effects 0.000 claims description 23
- 229910052751 metal Inorganic materials 0.000 claims description 14
- 239000002184 metal Substances 0.000 claims description 14
- 230000000694 effects Effects 0.000 claims description 12
- 239000010409 thin film Substances 0.000 claims description 11
- 239000000463 material Substances 0.000 claims description 8
- 239000002131 composite material Substances 0.000 claims description 7
- 239000010408 film Substances 0.000 claims description 7
- 239000011162 core material Substances 0.000 claims description 5
- 239000000470 constituent Substances 0.000 claims description 3
- 230000000149 penetrating effect Effects 0.000 claims description 2
- 238000010030 laminating Methods 0.000 claims 1
- 230000002093 peripheral effect Effects 0.000 claims 1
- 239000010955 niobium Substances 0.000 description 7
- 229910052758 niobium Inorganic materials 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 150000001875 compounds Chemical class 0.000 description 4
- 239000007788 liquid Substances 0.000 description 4
- 229910002480 Cu-O Inorganic materials 0.000 description 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 239000001307 helium Substances 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 2
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 description 2
- 229910052757 nitrogen Inorganic materials 0.000 description 2
- 230000035515 penetration Effects 0.000 description 2
- 229910052718 tin Inorganic materials 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- 229910015901 Bi-Sr-Ca-Cu-O Inorganic materials 0.000 description 1
- 229910014454 Ca-Cu Inorganic materials 0.000 description 1
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910020018 Nb Zr Inorganic materials 0.000 description 1
- 229910001257 Nb alloy Inorganic materials 0.000 description 1
- 229910020012 Nb—Ti Inorganic materials 0.000 description 1
- 229910001069 Ti alloy Inorganic materials 0.000 description 1
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 description 1
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 1
- 229910000756 V alloy Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 229910052733 gallium Inorganic materials 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 238000003475 lamination Methods 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 150000002822 niobium compounds Chemical class 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000004544 sputter deposition Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
- 239000010936 titanium Substances 0.000 description 1
- 229910052719 titanium Inorganic materials 0.000 description 1
- 238000003949 trap density measurement Methods 0.000 description 1
- 150000003682 vanadium compounds Chemical class 0.000 description 1
Landscapes
- Measuring Magnetic Variables (AREA)
- Superconductor Devices And Manufacturing Methods Thereof (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、超電導磁石の励磁方法に関し、更に詳しく
は、発生磁界の強さをコントロールすることの出来る超
電導磁石の励磁方法に関するものである。Description: TECHNICAL FIELD The present invention relates to a method of exciting a superconducting magnet, and more particularly, to a method of exciting a superconducting magnet capable of controlling the strength of a generated magnetic field.
（従来の技術） 近時、高温度で超電導状態を示す多くの超電導体が発
見され、その応用研究が各方面で鋭意進められるように
なった。磁気特性を利用した応用分野もその重要な一翼
を担い、特に超電導磁石は発生磁界の強さが大であるこ
とから、様々な分野での実用価値が高く、その一層の技
術開発が期待されている。(Prior Art) Recently, many superconductors exhibiting a superconducting state at a high temperature have been discovered, and their application research has been earnestly promoted in various fields. Application fields utilizing magnetic properties also play an important role, and in particular, superconducting magnets have high practical magnetic fields due to their large generated magnetic field, and further technological development is expected. I have.
（発明が解決しようとする課題） ところで、超電導体を励磁する方法としては、超電導
コイルに永久電流を流す方法と、超電導体を外部磁界に
晒した後この外部磁界を取り去り超電導体に磁束をトラ
ップさせるようにする方法とがある。後者の方法の場
合、超電導体は夫々固有の磁気特性を有し、励磁後の磁
束密度は各超電導体でほぼ一定であるとされていた。そ
の為、発生磁界の強さを可変して用いたい場合は、夫々
に対応した数種の超電導体を準備する必要があり、しか
も所望の磁束密度に完全に一致する保証もなかった。(Problems to be Solved by the Invention) As a method of exciting a superconductor, a method of passing a permanent current to a superconducting coil and a method of exposing the superconductor to an external magnetic field, removing the external magnetic field, and trapping magnetic flux in the superconductor are described. There is a way to make it happen. In the case of the latter method, the superconductors have their own magnetic properties, and the magnetic flux density after excitation is considered to be substantially constant in each superconductor. Therefore, when it is desired to use the generated magnetic field with variable strength, it is necessary to prepare several kinds of superconductors corresponding to each of them, and there is no guarantee that the magnetic flux density completely matches the desired magnetic flux density.
本発明者等は、各種超電導体の磁気特性を探求する過
程で、第１種超電導体以外の超電導体を或る定まった磁
界の変化モードの中に置いた後、この環境磁界を最終的
にゼロにした時に、夫々の磁界の変化モード対応した密
度の磁束が超電導体にトラップされることを知見し、こ
の知見をもとに発生磁界の強さを任意にコントロールす
ることが出来る新規な超電導体の励磁方法を完成するに
至り、ここに本発明を提供せんとするものである。In the process of exploring the magnetic properties of various superconductors, the present inventors place a superconductor other than the first type superconductor in a certain fixed magnetic field change mode, and finally reduce this environmental magnetic field. A new superconductivity that can control the strength of the generated magnetic field arbitrarily based on the knowledge that the magnetic flux of the density corresponding to the change mode of each magnetic field is trapped by the superconductor when it is set to zero The present invention is provided here after completing the body excitation method.
（課題を解決するための手段） 上記目的を達成する本発明の超電導磁石の励磁方法
は、最大磁気遮蔽量以上の強さの磁界に晒されたときに
は混合状態に移行する超電導体を構成部材として含むシ
ート状若しくは筒状成形体を、ゼロから上記混合状態領
域に亘り磁界の強さを可変することの出来る磁場発生装
置に配置し、該磁場発生装置による環境磁界の強さを増
加し混合状態領域内の所定の強さにまで至らしめた後環
境磁界の強さを減少させ最終的にゼロとすることによ
り、上記成形体に所望密度の磁束をトラップさせるよう
にしたことを要旨とするものである。(Means for Solving the Problems) A method for exciting a superconducting magnet according to the present invention, which achieves the above object, comprises, as a constituent member, a superconductor which transitions to a mixed state when exposed to a magnetic field having a strength not less than a maximum magnetic shielding amount. The sheet-like or cylindrical molded body containing the magnetic material is arranged in a magnetic field generator capable of varying the magnetic field intensity from zero to the above-mentioned mixed state region. After reaching a predetermined strength in the area, the strength of the environmental magnetic field is reduced and finally set to zero, so that a magnetic flux of a desired density is trapped in the molded body. It is.
上記励磁方法に採用される成形体としては、本出願人
が過去に提案した（特開昭61−183979号公報、特開昭63
−233577号公報、特願昭63−200795号、特願昭63−1324
48号、特願昭63−250546号及び特願昭63−307630号等）
いくつかの超電導磁気遮蔽体等と略同様の構成のものが
採用され、具体的には、 超電導薄膜層と金属シートとを積層一体としたシート
状物、 環帯幅が2mm以上の超電導薄膜層と熱伝導性及び電気
伝導性の良い金属層との積層閉環ディスク状複合シート
と、該複合シートと同形状の閉環ディスク状間隙材とを
重層して成るシート状物、 両端若しくは一端開放の筒状金属芯材と、該芯材の周
体を被装し少なくとも該芯材の軸線の廻りに関して電気
的に閉環状態とされた超電導フィルムとより成る筒状
物、 等が挙げられる。As a molded article used in the above-mentioned excitation method, the present applicant has proposed in the past (Japanese Patent Application Laid-Open Nos.
No. 233577, Japanese Patent Application No. 63-200795, Japanese Patent Application No. 63-1324
No. 48, Japanese Patent Application No. 63-250546, Japanese Patent Application No. 63-307630, etc.)
It employs a structure similar to some superconducting magnetic shields, etc., specifically, a sheet-like material in which a superconducting thin film layer and a metal sheet are laminated and integrated, a superconducting thin film layer with an annular width of 2 mm or more. Ring-shaped disc-shaped composite sheet composed of a metal sheet having good thermal conductivity and electric conductivity, and a ring-shaped disc-shaped gap member having the same shape as the composite sheet, a sheet-like material, And a superconducting film covered with a metal core material and a ring-shaped superconducting film which is electrically closed at least around the axis of the core material.
上記の場合、超電導薄膜層として、厚みと磁気遮
蔽効果との関係に於いて、その磁気遮蔽効果が厚みの増
大と共に原点から急激に増大し爾後緩やかな勾配をもっ
て漸増する如き曲線を描くものであり、且つその厚みが
磁気遮蔽効果の特性曲線に於いて前記漸増状態に移行す
る変曲点に対応する厚み以下であるものが、最大磁気遮
蔽量が高く望ましく採用される。この場合、超電導薄膜
層と金属層とを多数交互に積層することが望ましい。In the above case, as the superconducting thin film layer, in the relationship between the thickness and the magnetic shielding effect, the magnetic shielding effect draws a curve such that it increases sharply from the origin as the thickness increases, and then gradually increases with a gentle gradient. If the thickness is less than or equal to the thickness corresponding to the inflection point at which the transition to the gradually increasing state is made in the characteristic curve of the magnetic shielding effect, the maximum magnetic shielding amount is desirably high and preferably employed. In this case, it is desirable that a large number of superconducting thin film layers and metal layers are alternately laminated.
亦、のシート状物として、厚み方向に貫く多数の
小孔を有するものとすれば超電導遮蔽作用に電磁遮蔽作
用が付加され、最大磁気遮蔽量が高くなることにより最
大磁束トラップ密度が高くなり上記同様望ましく採用さ
れる。Also, if the sheet-like material has a large number of small holes penetrating in the thickness direction, the electromagnetic shielding effect is added to the superconducting shielding effect, and the maximum magnetic shielding amount is increased, so that the maximum magnetic flux trap density is increased. It is also desirably employed.
更に、の場合の超電導フィルムとして、で得ら
れるシート体を充当させることも可能である。Further, as the superconducting film in the case of (1), it is also possible to apply the sheet body obtained in (1).
ここでの場合に、超電導薄膜層の環帯幅を2mm以上
としたのは、磁界内に置いた時に超電導薄膜層の環帯上
に渦電流を発生させ、この渦電流の発生によって完全反
磁性及び反磁性を惹起させんとするためである。即ち、
2mm未満の場合は上記渦電流が発生しにくく、完全反磁
性及び反磁性による混合状態での磁気特性が低下する傾
向となり、また加工性も乏しくなる。In this case, the reason why the ring width of the superconducting thin film layer is set to 2 mm or more is that an eddy current is generated on the ring band of the superconducting thin film layer when placed in a magnetic field, and this eddy current causes complete diamagnetism. And to induce diamagnetism. That is,
If it is less than 2 mm, the eddy current is less likely to be generated, and the magnetic properties in a mixed state due to complete diamagnetism and diamagnetism tend to decrease, and workability is poor.
上記及びの成形体の一構成部材としての超電導
薄膜層及び超電導フィルムの実体である超電導体は、第
１種超電導体を除き超電導体であり、最大磁気遮蔽量以
上の強さの磁界に晒されたときには混合状態に移行する
性質を有するものである。具体的には、ニオブ金属、ニ
オブ系化合物〔NbN、NbC、Nb3Sn、Nb3Al、Nb3Ga、Nb3G
e、Nb3（AlGe）、NbN・TiN混晶体等〕、ニオブ系合金
（Nb−Ti合金、Nb−Zr合金等）、バナジウム系化合物及
びバナジウム系合金（V3Ga）、セラミック系超電導材料
（Ba−Ｙ−Cu−Ｏ系化合物、La−Sr−Cu−Ｏ系化合物、
Bi−Sr−Ca−Cu−Ｏ系化合物、Tl−Ba−Ca−Cu−Ｏ系化
合物等）やジェブレル超電導体（PbMo6S6等）などが採
用される。The superconductor which is the substance of the superconducting thin film layer and the superconducting film as a constituent member of the above-mentioned and molded bodies is a superconductor except for a type 1 superconductor, and is exposed to a magnetic field having a strength not less than the maximum magnetic shielding amount. It has the property of transitioning to a mixed state when it occurs. Specifically, niobium metal, niobium compounds [NbN, NbC, Nb 3 Sn, Nb 3 Al, Nb 3 Ga, Nb 3 G
e, Nb 3 (AlGe), NbN / TiN mixed crystal, etc.], niobium alloy (Nb-Ti alloy, Nb-Zr alloy, etc.), vanadium compound and vanadium alloy (V 3 Ga), ceramic superconducting material ( Ba-Y-Cu-O-based compound, La-Sr-Cu-O-based compound,
Bi-Sr-Ca-Cu- O -based compound, Tl-Ba-Ca-Cu -O type compound) and Jebureru superconductor (PbMo 6 S 6, etc.) and the like are employed.
斯かる超電導体の薄膜層或いはフィルムは、上述の如
く金属層と積層一体とされていることが望ましいが、該
金属層と超電導体層との積層一体化は、スパッタ法或い
は圧延された超電導シートの表面に金属を電着し、更に
この電着複合体を多層化する場合は該複合体を低融点金
属浴に浸漬した後圧着するなどの方法によってなされ
る。また、金属層としては銅、アルミニウム、ニッケ
ル、ステンレススチール、チタン、ニオブ及びニオブ−
チタン合金等の熱伝導性及び電気伝導性の良い金属が採
用される。The thin film layer or film of such a superconductor is desirably laminated and integrated with a metal layer as described above. The lamination and integration of the metal layer and the superconductor layer are performed by a sputtering method or a rolled superconducting sheet. When a metal is electrodeposited on the surface of the composite and the electrodeposited composite is further multilayered, the composite is immersed in a low-melting-point metal bath and then compression-bonded. Further, as the metal layer, copper, aluminum, nickel, stainless steel, titanium, niobium and niobium-
A metal having good heat conductivity and electric conductivity such as a titanium alloy is employed.
その他上記成形体の変更態様としては、前記先行出願
に開示されたものと略同様の構成のものが採用される。As other modified forms of the above-mentioned molded body, those having substantially the same configuration as that disclosed in the above-mentioned prior application are employed.
また、磁場発生装置としては、超伝導マグネット或い
は常電導マグネットが採用可能である。As the magnetic field generator, a superconducting magnet or a normal conducting magnet can be used.
（作用） 本発明の超電導磁石の励磁方法についての作用を説明
するに当り、その基本的原理を第１図及び第２図を採っ
て説明する。第１図は、環境磁界の強さBo（Ｘ軸）と、
該環境磁界内に置かれた第１種超電導体以外の超電導体
の近傍若しくはその内部空間で検出される磁界の強さBr
（Ｙ軸）との関係を表す磁気特性曲線図である。(Operation) In describing the operation of the method for exciting a superconducting magnet of the present invention, the basic principle will be described with reference to FIGS. 1 and 2. FIG. FIG. 1 shows the intensity of the environmental magnetic field Bo (X axis),
The strength of a magnetic field Br detected in the vicinity of or inside the superconductor other than the first-class superconductor placed in the environmental magnetic field
FIG. 6 is a magnetic characteristic curve diagram showing a relationship with (Y axis).
図に於いて、Boを増加させB1（Ａ点）に至る間Brはゼ
ロである。これは上記超電導体の完全反磁性特性（マイ
スナー効果）によるものであり、ゼロ〜B1は該超電導体
により環境磁界が完全に遮断された領域で、B1は下部臨
界磁界（Hc1）即ち最大磁気遮蔽量である。次いで、Bo
をB1より大きくしてゆくと一部磁束が貫通し、検出器に
よりBrが検出される。これは、完全反磁性と反磁性との
混合状態の領域であり、やがて環境磁界と貫通磁界が等
しい点Ｃ（上部臨界磁界Hc2）に到達する。この上部臨
界磁界Hc2を超えた時点で環境磁界Boの増加を停止し、
これを逆に減少させていくと、超電導体には磁束がトラ
ップされる為、BrはＣ〜Ｅの如き曲線を描き、Boがゼロ
になると超電導体にB3の磁束がトラップされることにな
る。Boの磁界の方向を逆方向に作用させた時にはBrは逆
向きの磁界を検出し、第１図の第３象限にも同様の曲線
（Ａ′〜Ｃ′〜Ｅ′）が対象に描かれる。また超電導体
にB3（−B3）の磁束がトラップされた状態で上記とは逆
の方向で環境磁界Boを作用させると、超電導体はその変
化分だけ減らそう（増やそう）とし環境磁界Boが−B1
（B1）の点でBrはゼロとなり、この間B3〜−B1（−B3〜
B1）の曲線を描く。従って、超電導状態を維持したまま
上記操作を繰り返すと、図の如き閉環ループ状の曲線を
描くことになる。In the figure, Br is zero while increasing Bo and reaching B1 (point A). This is due to the perfect diamagnetism (Meissner effect) of the superconductor. Zero to B1 is a region where the environmental magnetic field is completely cut off by the superconductor, and B1 is the lower critical magnetic field (Hc1), that is, the maximum magnetic shielding. Quantity. Then Bo
When B is made larger than B1, a part of the magnetic flux penetrates, and Br is detected by the detector. This is a region where the complete diamagnetism and the diamagnetism are mixed, and eventually reaches the point C (the upper critical magnetic field Hc2) where the environmental magnetic field and the penetration magnetic field are equal. When this upper critical magnetic field Hc2 is exceeded, the increase of the environmental magnetic field Bo is stopped,
Conversely, if this is reduced, the magnetic flux is trapped in the superconductor, so Br draws a curve such as CE, and when Bo becomes zero, the magnetic flux of B3 is trapped in the superconductor. . When the direction of the magnetic field of Bo is applied in the opposite direction, Br detects the magnetic field in the opposite direction, and similar curves (A 'to C' to E ') are drawn in the third quadrant of FIG. . When the magnetic field B3 (-B3) is trapped in the superconductor and an environmental magnetic field Bo is applied in the opposite direction to the above, the superconductor tries to decrease (increase) by the change and the environmental magnetic field Bo increases. −B1
At the point of (B1), Br becomes zero. During this time, B3 to -B1 (-B3 to
Draw the curve of B1). Therefore, if the above operation is repeated while maintaining the superconducting state, a closed loop curve as shown in the figure will be drawn.
そして、Boの増加を混合状態領域の任意のB2で停止、
ここからBoを減少させんとすると、超電導体は上記同様
環境磁界の変化分だけ増やそうとし、その結果Brは点Ｂ
から点Ｄに至る間B4に維持される。斯かる挙動は鎖交磁
束不変の原理に基づくものと考えられる。そして、Ｄの
位置から更にBoを減少させるとＤ〜Ｅの曲線に沿い、Bo
がゼロになったときには上記同様B3の磁束が超電導体に
トラップされることになる。And the increase of Bo is stopped at any B2 in the mixed state area,
If Bo is to be reduced from this point, the superconductor tries to increase by the change in the environmental magnetic field as described above, and as a result, Br becomes the point B
Is maintained at B4 from the point D to the point D. Such a behavior is considered to be based on the principle of flux linkage invariance. Then, when Bo is further reduced from the position of D, along the curves D to E, Bo
Becomes zero, the magnetic flux of B3 is trapped in the superconductor as described above.
亦、環境磁界BoをB1からB5の間の任意の強さａに設定
すると、Brはｂとなり、この状態からBoを減少させる
と、Brはｂを維持しBoがゼロになった時には超電導体に
ｃの磁束（ｂ＝ｃで一定）がトラップされることにな
る。本発明者等は、上記Ｂ−Ｄ間及びｂ−ｃ間の挙動に
着目し、多くの試験を繰り返した結果、B4或いはｂ
（ｃ）では維持精度が1/1010と極めて高精度であること
を知見した。従って、環境磁界BoをB5以上に増加させた
後ゼロに戻した時には、超電導体にはB3の磁界が確実に
トラップされる。また環境磁界BoをB1からB5の間の任意
の強さａに設定した後ゼロにした時には、各超電導体固
有の特性曲線によって規制された０からB3の間の強さの
磁束ｃがトラップされることになる。即ち、超電導体に
ｃの強さの磁束をトラップさせたい場合、各超電導体に
固有の磁気特性曲線から読み取ったａの強さに環境磁界
を設定した後上記操作を行なえば良いことになる。Also, when the environment magnetic field Bo is set to an arbitrary strength a between B1 and B5, Br becomes b. When Bo is reduced from this state, Br is maintained at b and when the Bo becomes zero, the superconductor Then, the magnetic flux of c (constant at b = c) is trapped. The present inventors focused on the behavior between BD and between bc, and as a result of repeating many tests, B4 or b
(C) the maintenance accuracy was found that a highly accurate 1/10 10. Therefore, when the environmental magnetic field Bo is increased to B5 or more and then returned to zero, the magnetic field of B3 is reliably trapped in the superconductor. When the environment magnetic field Bo is set to an arbitrary strength a between B1 and B5 and then set to zero, a magnetic flux c having a strength between 0 and B3 regulated by a characteristic curve specific to each superconductor is trapped. Will be. That is, when it is desired to trap a magnetic flux having a strength c in the superconductor, the above operation may be performed after setting the environmental magnetic field to the strength a read from the magnetic characteristic curve unique to each superconductor.
上記挙動を、Bo（Ｘ軸）とΔＢ（ΔＢ＝Bo−Br…Ｙ
軸）との関係を示した第２図で更に考察する。等電導状
態を維持したまま上記の如く操作すると、Bo・ΔＢ曲線
はＸ軸及びＹ軸に対象な略菱形の閉環ループ曲線を描
く。ここで、上記の如く超電導体を極低温下（超電導状
態となる条件）に置き、環境磁界Boの強さをゼロからB5
を超えB2に至らしめるとΔＢは点Ａ（最大磁気遮蔽点）
を経て点Ｂに至る。ここから環境磁界Boの強さを減少さ
せると、Ｃ〜Ｅ曲線上の点Ｄに至る。Ｂ〜Ｄ間ではBrが
一定であるので、ΔＢはBoに正比例し図の如く勾配１の
直線を描く。更にBoの減少を継続させるとＤ〜Ｅ曲線に
沿った後ゼロになった時にはＹ軸上の点Ｅに至る。ま
た、環境磁界Boの強さをB1〜B5間ののａにまで増加する
と、ΔＢは点Ａを経てｂに至る。この状態から環境磁界
Boの強さを減少させると、上記同様勾配１の直線を辿
り、BoがゼロになったときにはＹ軸上の点ｃに至る。上
記点Ｅ或いはｃに於けるΔＢは、超電導にトラップされ
た磁束の強さであり、このトラップ磁束の強さは、環境
磁界Boの強さをB5以上にした場合はB3に、B1〜B5間の任
意の強さａにした場合は０〜B3間のｃとなる。The above behavior is represented by Bo (X axis) and ΔB (ΔB = Bo−Br... Y
Further consideration is given in FIG. When the above operation is performed while maintaining the isoconducting state, the Bo · ΔB curve draws a substantially diamond-shaped closed loop curve on the X axis and the Y axis. Here, as described above, the superconductor is placed under cryogenic temperature (the condition of superconducting state), and the intensity of the environmental magnetic field Bo is changed from zero to B5.
ΔB is point A (maximum magnetic shielding point) when B2 is exceeded
To point B. When the intensity of the environmental magnetic field Bo is reduced from this point, a point D is reached on the CE curve. Since Br is constant between B and D, ΔB is directly proportional to Bo and draws a straight line with a gradient 1 as shown in the figure. If the value of Bo continues to be reduced, it reaches point E on the Y-axis when it becomes zero after following the D to E curves. When the intensity of the environmental magnetic field Bo is increased to a between B1 and B5, ΔB reaches b through the point A. From this state, the environmental magnetic field
When the strength of Bo is reduced, a straight line having a slope of 1 is followed in the same manner as described above, and when Bo becomes zero, it reaches point c on the Y axis. ΔB at the above point E or c is the intensity of the magnetic flux trapped by the superconductivity. If an arbitrary strength a is used, c is between 0 and B3.
而して、本発明は上記基本原理を利用するものであ
り、各超電導体を一構成部材とする成形体の第２図に示
す如き磁気特性データを予め採取し、これを磁界の強さ
が可変出来る磁場発生装置内に配置して超電導状態（液
体ヘリウム或いは液体窒素による極低温状態）に維持さ
せた上で、環境磁界を作用させることにより上記成形体
を所望の強さに励磁することが出来る。即ち、成形体を
B3の強さに励磁したい場合は、環境磁界Boの強さをB5以
上にした後減少させてゼロにする。また、０〜B3間の所
望の強さに励磁したい場合、上記特性曲線に於けるＹ軸
上に任意の点ｃ（励磁したい磁束の強さ）から勾配１の
直線を描きＥ′〜Ａ〜Ｃ曲線との交点ｂに対応するＸ軸
上の点ａを読み取り、環境磁界Boの強さをａにまで増加
しその後ゼロに減少させるよう操作する。これにより、
０〜B3間の所望の強さに正しく励磁された超電導磁石を
得ることが出来る。尚、ｃの強さの超電導磁石を得んと
して環境磁界Boの強さを誤ってａ以上にしてしまった場
合、引続きB5以上に増加させその後ゼロにまで下げ、一
旦成形体にB3の磁束をトラップさせ、その後上記勾配１
の直線とＥ〜Ｃ′曲線との交点ｄに対応するＸ軸上の点
ｅにまで環境磁界Boを増加（上記とは逆方向）させ、爾
後再びゼロに戻すようにすれば良い。亦、成形体に上記
とは逆方向の磁束をトラップさせたい場合は、上記特性
曲線の第２、第３象限（一部第１象限も含む）に於ける
Ｘ軸から読み取った環境磁界Bo（上記とは逆向き）を作
用させることにより、同様に行なうことが出来る。Thus, the present invention utilizes the above-mentioned basic principle, and collects in advance the magnetic characteristic data as shown in FIG. It is possible to excite the compact to a desired strength by applying an environmental magnetic field while maintaining it in a superconducting state (ultra-low temperature state by liquid helium or liquid nitrogen) by disposing it in a variable magnetic field generator. I can do it. That is, the compact
When it is desired to excite to the intensity of B3, the intensity of the environmental magnetic field Bo is set to B5 or more and then reduced to zero. When it is desired to excite to a desired intensity between 0 and B3, a straight line having a gradient 1 is drawn from an arbitrary point c (the intensity of the magnetic flux to be excited) on the Y-axis in the above characteristic curve. A point a on the X-axis corresponding to the intersection b with the C curve is read, and an operation is performed so that the intensity of the environmental magnetic field Bo is increased to a and then reduced to zero. This allows
It is possible to obtain a superconducting magnet that is properly excited to a desired strength between 0 and B3. If the strength of the environmental magnetic field Bo is erroneously increased to a or more in order to obtain a superconducting magnet having a strength of c, the magnetic field B is continuously increased to B5 or more and then reduced to zero, and the magnetic flux of B3 is once applied to the compact. Trap and then the gradient 1
The environmental magnetic field Bo may be increased (in the opposite direction) to a point e on the X-axis corresponding to the intersection d between the straight line and the E to C 'curve, and then returned to zero again. When it is desired to trap the magnetic flux in the opposite direction to the above-mentioned direction, the environmental magnetic field Bo () read from the X axis in the second and third quadrants (including a part of the first quadrant) of the characteristic curve described above. The same effect can be obtained by applying the opposite direction.
（実施例） 次に本発明の実施例を添付図面に基づき説明する。第
３図は本発明の励磁方法に採用される装置の一例を示す
概略縦断面説明図、第４図乃至第７図はこれに採用され
る成形体の種々の態様を示す斜視図である。(Example) Next, an example of the present invention is described based on an accompanying drawing. FIG. 3 is a schematic longitudinal sectional explanatory view showing an example of an apparatus employed in the excitation method of the present invention, and FIGS. 4 to 7 are perspective views showing various aspects of a molded body employed therein.
第３図に於いて、低温容器１内には超電導マグネット
２が配設され、該超電導マグネット２からは電流印加用
のリード線21、21が導出されている。この超電導マグネ
ット２の内部空間には上述の如く構成された成形体３が
配置されている。低温容器１は内外二重の真空層11、11
から成り、該真空層11、11間には液体窒素４が充填され
また該低温容器１内には液体ヘリウム５が満たされ、超
電導マグネット２及び成形体３が超電導状態に保持され
るようになされている。In FIG. 3, a superconducting magnet 2 is provided in a low-temperature container 1, and leads 21, 21 for applying a current are led out of the superconducting magnet 2. In the internal space of the superconducting magnet 2, the formed body 3 configured as described above is arranged. The cryogenic vessel 1 has a double vacuum layer 11, 11 inside and outside.
Liquid nitrogen 4 is filled between the vacuum layers 11 and 11 and liquid helium 5 is filled in the low-temperature container 1 so that the superconducting magnet 2 and the compact 3 are maintained in a superconducting state. ing.
第３図では成形体３が第４図の如き円筒体であること
を示し、この円筒状成形体３の筒内部にホール素子等の
磁気検出器６が設置されている。FIG. 3 shows that the molded body 3 is a cylindrical body as shown in FIG. 4, and a magnetic detector 6 such as a Hall element is installed inside the cylinder of the cylindrical molded body 3.
斯くして、上記の如く整えられた装置に於いて、超電
導マグネット２に電流を印加し、その内部空間に磁界を
発生させ、第２図の特性曲線から読み取った所望の強さ
になるまで磁界の強さを増大させる。この後、環境磁界
の強さを減少させてゼロにすれば、成形体には所望の磁
束がトラップされ、検出器６によってこれが検出され
る。Thus, in the device arranged as described above, a current is applied to the superconducting magnet 2 to generate a magnetic field in its internal space, and the magnetic field is obtained until the desired strength read from the characteristic curve of FIG. Increase the strength of Thereafter, if the intensity of the environmental magnetic field is reduced to zero, a desired magnetic flux is trapped in the molded body, and this is detected by the detector 6.
第５図乃至第７図は、成形体３の種々の態様を示し、
第５図は一端が閉塞された筒状体であり、第６図はディ
スク状シート体、第７図は環状シート体であることを示
す。第４図に示す両端開放の成形体３を含めこれらはい
ずれも前記先行出願で開示の方法と同様にして調製され
るものである。第４図及び第５図に示す成形体の場合、
上記検出器６はその筒内に置かれるが、第６図に示す成
形体の場合、環境磁界の磁束方向と反対面の近傍に、第
７図に示す成形体の場合その環内に置かれる。5 to 7 show various aspects of the molded body 3,
FIG. 5 shows a cylindrical body with one end closed, FIG. 6 shows a disk-shaped sheet body, and FIG. 7 shows a circular sheet body. All of these, including the open-ended molded body 3 shown in FIG. 4, are prepared in the same manner as the method disclosed in the above-mentioned prior application. In the case of the molded body shown in FIGS. 4 and 5,
The detector 6 is placed in the cylinder. In the case of the molded body shown in FIG. 6, it is placed near the surface opposite to the direction of the magnetic flux of the environmental magnetic field, and in the case of the molded body shown in FIG. .
（発明の効果） 叙上の如く、本発明の超電導磁石の励磁方法に於いて
は、各成形体の磁気特性曲線から読み取った強さの環境
磁界にした後、これをゼロにするだけで所望の強さに励
磁された超電導磁石を得ることが出来る。しかもこの励
磁磁界の強さは、本発明者等が知見した前記超電導体の
磁気特性に基づくものである為極めて精度が高い。(Effects of the Invention) As described above, in the method of exciting a superconducting magnet according to the present invention, it is desirable to set the environmental magnetic field of the strength read from the magnetic characteristic curve of each molded body, and then reduce this to zero. The superconducting magnet excited to the strength of can be obtained. Moreover, the strength of the exciting magnetic field is extremely high because it is based on the magnetic properties of the superconductor discovered by the present inventors.
このように特筆すべき効果を有する本発明は、その有
用価値は極めて大である。The present invention having such remarkable effects has extremely large useful value.
第３図は本発明の励磁方法に採用される装置の一例を示
す概略縦断面説明図、第４図乃至第７図はこれに採用さ
れる成形体の種々の態様を示す斜視図、第１図は環境磁
界の強さと該環境磁界内に置かれた超電導体の近傍若し
くはその内部空間で検出される磁界の強さとの関係を表
す磁気特性曲線図、第２図は環境磁界の強さと環境磁界
−貫通磁界との関係を表す磁気特性曲線図である。 （符号の説明） １……低温容器、２……磁場発生装置（超電導マグネッ
ト）、３……成形体、６……測定用検出器。FIG. 3 is a schematic longitudinal sectional explanatory view showing an example of an apparatus used in the excitation method of the present invention. FIGS. 4 to 7 are perspective views showing various aspects of a molded body used in the apparatus. FIG. 2 is a magnetic characteristic curve diagram showing the relationship between the strength of the environmental magnetic field and the strength of the magnetic field detected in the vicinity of or in the internal space of the superconductor placed in the environmental magnetic field. It is a magnetic characteristic curve figure showing the relationship between a magnetic field and a penetration magnetic field. (Explanation of reference numerals) 1... Low-temperature container, 2... Magnetic field generator (superconducting magnet), 3... Molded body, 6... Detector for measurement.
フロントページの続き (72)発明者 井上 勝 大阪府大阪市北区堂山町１番５号 高圧 ガス工業株式会社内 (58)調査した分野(Int.Cl.6，ＤＢ名) H01F 6/00Continuation of front page (72) Inventor Masaru Inoue 1-5 Doyama-cho, Kita-ku, Osaka-shi, Osaka High-pressure gas industry Co., Ltd. (58) Field surveyed (Int. Cl. 6 , DB name) H01F 6/00
Claims (7)
たときには混合状態に移行する超電導体を構成部材とし
て含むシート状若しくは筒状成形体を、ゼロから上記混
合状態領域に亘り磁界の強さを可変することの出来る磁
場発生装置内に配置し、該磁場発生装置による環境磁界
の強さを増加し混合状態領域内の所定の強さにまで至ら
しめた後環境磁界の強さを減少させ最終的にゼロとする
ことにより、上記成形体に所望密度の磁束をトラップさ
せるようにした超電導磁石の励磁方法。1. A sheet-like or cylindrical molded body containing a superconductor which moves into a mixed state when exposed to a magnetic field having a strength equal to or greater than the maximum magnetic shielding amount as a constituent member from zero to a magnetic field ranging from the mixed state region. Is placed in a magnetic field generator capable of varying the intensity of the ambient magnetic field, and after the intensity of the environmental magnetic field by the magnetic field generator is increased to a predetermined level in the mixed state region, the intensity of the environmental magnetic field A method for exciting a superconducting magnet, wherein the magnetic flux of a desired density is trapped in the compact by reducing the value of the magnetic flux to zero.
とを積層一体としたシート状物である請求項１記載の励
磁方法。2. The excitation method according to claim 1, wherein the molded body is a sheet-like material in which a superconducting thin film layer and a metal sheet are integrally laminated.
薄膜層と熱伝導性及び電気伝導性の良い金属層との積層
閉環ディスク状複合シートと、該複合シートと同形状の
閉環ディスク状間隙材とを重層して成るシート状物であ
る請求項１記載の励磁方法。3. A laminated ring-closing disc-shaped composite sheet comprising a superconducting thin film layer having an annular width of 2 mm or more and a metal layer having good thermal and electrical conductivity, and a ring-closing ring having the same shape as the composite sheet. 2. The excitation method according to claim 1, wherein the excitation method is a sheet-like material obtained by laminating a disk-shaped gap material.
の関係に於いて、その磁気遮蔽効果が厚みの増大と共に
原点から急激に増大し爾後緩やかな勾配をもって漸増す
る如き曲線を描くものであり、且つその厚みが磁気遮蔽
効果の特性曲線に於いて前記漸増状態に移行する変曲点
に対応する厚み以下であることを特徴とする請求項１又
は２の記載の励磁方法。4. The superconducting thin film draws a curve in the relationship between thickness and magnetic shielding effect such that the magnetic shielding effect increases sharply from the origin with an increase in thickness and then gradually increases with a gentle gradient. 3. The excitation method according to claim 1, wherein the thickness is not more than a thickness corresponding to an inflection point at which the characteristic curve of the magnetic shielding effect shifts to the gradually increasing state.
小孔を有するものである請求項１又は２記載の励磁方
法。5. The excitation method according to claim 1, wherein the sheet-like material has a number of small holes penetrating in a thickness direction.
状金属芯材と、該芯材の周体を被装し少なくとも該芯材
の軸線の廻りに関して電気的に閉環状態とされた超電導
フィルムとより成る筒状物である請求項１記載の励磁方
法。6. A superconducting body in which said molded body is covered with a cylindrical metal core material having both ends or one end open and a peripheral body of said core material and is electrically closed at least around an axis of said core material. 2. The excitation method according to claim 1, wherein the excitation method is a cylindrical object formed of a film.
記載のシート体により成る請求項６記載の励磁方法。7. An exciting method according to claim 6, wherein said superconducting film comprises the sheet member according to claim 2 or 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1122017A JP2781838B2 (en) | 1989-05-15 | 1989-05-15 | Excitation method of superconducting magnet |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1122017A JP2781838B2 (en) | 1989-05-15 | 1989-05-15 | Excitation method of superconducting magnet |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02301103A JPH02301103A (en) | 1990-12-13 |
| JP2781838B2 true JP2781838B2 (en) | 1998-07-30 |
Family
ID=14825515
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1122017A Expired - Fee Related JP2781838B2 (en) | 1989-05-15 | 1989-05-15 | Excitation method of superconducting magnet |
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| Country | Link |
|---|---|
| JP (1) | JP2781838B2 (en) |
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- 1989-05-15 JP JP1122017A patent/JP2781838B2/en not_active Expired - Fee Related
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