JPH0685335A - Switch superconductive magnet protective circuit - Google Patents

Switch superconductive magnet protective circuit

Info

Publication number
JPH0685335A
JPH0685335A JP4260573A JP26057392A JPH0685335A JP H0685335 A JPH0685335 A JP H0685335A JP 4260573 A JP4260573 A JP 4260573A JP 26057392 A JP26057392 A JP 26057392A JP H0685335 A JPH0685335 A JP H0685335A
Authority
JP
Japan
Prior art keywords
switch
circuit
electrodes
superconducting magnet
protection circuit
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.)
Granted
Application number
JP4260573A
Other languages
Japanese (ja)
Other versions
JP2708678B2 (en
Inventor
Akihiko Kishikawa
昭彦 岸川
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Railway Technical Research Institute
Original Assignee
Railway Technical Research Institute
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Railway Technical Research Institute filed Critical Railway Technical Research Institute
Priority to JP4260573A priority Critical patent/JP2708678B2/en
Publication of JPH0685335A publication Critical patent/JPH0685335A/en
Application granted granted Critical
Publication of JP2708678B2 publication Critical patent/JP2708678B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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  • Containers, Films, And Cooling For Superconductive Devices (AREA)
  • Arc-Extinguishing Devices That Are Switches (AREA)

Abstract

PURPOSE:To provide a switch for a protective circuit, which consumes the energy accumulated in a superconductive coil at abnormality with a protective resistor, and breaks the circuit constitution to the resistor at magnetization and demagnetization work so as to improve magnetization and demagnetization property thereby obviating external control, in series with the protective resistor. CONSTITUTION:A switch 5 for a superconductive magnet protective circuit constitutes the circuit by the arc discharge generated between electrodes at the initial stage of protection, making use of the energy accumulated in a superconductive coil 1, as the circuit constitution at quenching of a superconductive coil 1 or trouble occurrence of a permanent current switch 2, and then, constitutes the circuit by fusing an electrode by the arc heat.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は超電導コイルのクエンチ
や永久電流スイッチのトラブル発生時に、超電導磁石を
保護するために設ける保護システムに組み込まれる保護
回路用スイッチに関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch for a protection circuit incorporated in a protection system provided to protect a superconducting magnet when a superconducting coil is quenched or a trouble occurs in a permanent current switch.

【0002】[0002]

【従来の技術】図3は従来技術における保護システムの
考え方を示すものである。1は超電導コイル、2は永久
電流スイッチ、3は電流リード線、4は保護抵抗体、6
は励磁用の電源である。図3において、励磁用の電源6
は超電導コイル1への励磁または消磁作業が終了すると
切り放されるものである。また超電導コイル1に流れて
いる電流は超電導状態の超電導コイル1と永久電流スイ
ッチ2で作られる閉回路を流れている。そして、この回
路に異常が発生したときに同回路から放出されるエネル
ギを吸収する目的で、この回路と直列に保護抵抗体4が
組み込まれている。したがって、超電導コイル1と保護
抵抗体4の間を接続・分離する手段は設けられていな
い。図3において、超電導磁石を励磁する場合には、永
久電流スイッチ2を開いた状態で通電し、超電導コイル
1に所定の電流を流した後に永久電流スイッチ2を閉じ
る。これにより、超電導コイル1の電流は励磁用の電源
6を切り離した後においても永久電流モードとなり内部
に電流が流れ続け、強力な磁石を保ち続けるものであ
る。次に超電導磁石を消磁する場合には永久電流モード
となっている超電導コイル1に対して、永久電流スイッ
チ2を閉じた状態で励磁用の電源6から通電を開始し、
超電導コイル1に流れている電流値まで電流をあげた
後、永久電流スイッチ2を開き零アンペアまで下げてい
く。これによって超電導コイル1の強力な磁力がなくな
る。このように超電導磁石を励磁または消磁する場合、
コイル両端に発生する電圧Vは、 V=L・(dI/dT) となる。ここにLは超電導コイルの自己インダクタン
ス、dI/dTは励磁または消磁時の超電導コイルに流れる
電流の変化率である。そしてこの電圧Vにより、励磁及
び消磁時には保護回路を切り離す手段が無いため、保護
抵抗には超電導磁石の保護時のみでなく励磁及び消磁時
にも電流が流れることになる。次に図4は、保護抵抗体
と直列にダイオードを接続した従来技術の他の一例であ
る。1は超電導コイル、2は永久電流スイッチ、3は電
流リード線、4は保護抵抗体、6は励磁用の電源、9は
ダイオードである。ダイオード9は保護抵抗体4に流れ
る特定の方向の電流を阻止しようとする考え方が取り入
れられている。この回路における超電導磁石の励磁及び
消磁は図3の場合と同様であるが、ダイオード9が励磁
時に流れる電流を阻止する方向につけられているため保
護抵抗体4には分流せず、したがって励磁時間の短縮が
図られている。ダイオード9は、場合によってはサイリ
スタが対象として考えられる。
2. Description of the Related Art FIG. 3 shows the concept of a protection system in the prior art. 1 is a superconducting coil, 2 is a permanent current switch, 3 is a current lead wire, 4 is a protective resistor, 6
Is a power supply for excitation. In FIG. 3, the excitation power source 6
Is cut off when the operation of exciting or demagnetizing the superconducting coil 1 is completed. The current flowing through the superconducting coil 1 flows through a closed circuit made up of the superconducting coil 1 in the superconducting state and the permanent current switch 2. A protective resistor 4 is incorporated in series with this circuit for the purpose of absorbing the energy released from the circuit when an abnormality occurs in this circuit. Therefore, no means for connecting and disconnecting the superconducting coil 1 and the protective resistor 4 is provided. In FIG. 3, when exciting the superconducting magnet, the permanent current switch 2 is energized in an open state, a predetermined current is passed through the superconducting coil 1, and then the permanent current switch 2 is closed. As a result, the current of the superconducting coil 1 is in the permanent current mode even after the power source 6 for excitation is disconnected, and the current continues to flow inside to keep a strong magnet. Next, when demagnetizing the superconducting magnet, the superconducting coil 1 in the permanent current mode is energized from the excitation power source 6 with the permanent current switch 2 closed.
After raising the current to the value of the current flowing in the superconducting coil 1, the permanent current switch 2 is opened and lowered to zero amperes. This eliminates the strong magnetic force of the superconducting coil 1. When exciting or demagnetizing a superconducting magnet like this,
The voltage V generated across the coil is V = L · (dI / dT). Here, L is the self-inductance of the superconducting coil, and dI / dT is the rate of change of the current flowing through the superconducting coil during excitation or demagnetization. Because of this voltage V, there is no means for disconnecting the protection circuit at the time of excitation and demagnetization, so that a current flows through the protective resistance not only when the superconducting magnet is protected but also when it is excited and demagnetized. Next, FIG. 4 shows another example of the prior art in which a diode is connected in series with a protective resistor. 1 is a superconducting coil, 2 is a permanent current switch, 3 is a current lead wire, 4 is a protective resistor, 6 is a power source for excitation, and 9 is a diode. The diode 9 incorporates the idea of blocking the current flowing in the protective resistor 4 in a specific direction. Excitation and demagnetization of the superconducting magnet in this circuit are the same as in the case of FIG. 3, but since the diode 9 is oriented in the direction of blocking the current flowing during the excitation, it cannot be shunted to the protective resistor 4, and therefore the excitation time It is being shortened. The diode 9 may be considered as a thyristor in some cases.

【0003】[0003]

【発明が解決しようとする課題】従来技術でダイオード
が接続されていない回路構成では、保護抵抗体4の本来
の目的である、超電導コイル等のトラブル時のみでな
く、通常頻繁に行われる励磁や消磁作業時にも、超電導
コイル等の両端に発生する電圧Vにより保護抵抗体への
分流が発生し、励磁や消磁作業に時間を要するとともに
抵抗体にかなり大きな熱ロスが発生する。また従来技術
でダイオードが接続されているような回路構成で保護抵
抗体と直列にダイオードを配置し、励磁時の保護抵抗体
への分流を阻止する考え方では、励磁時の問題解決に対
する有効な手段ではあるものの、消磁作業時には発生電
圧は逆方向となるために、作業時間の短縮及び分流阻止
機能は得られないことになる。このためダイオードの代
わりにサイリスタを採用することにより、両方向の分流
を阻止する考え方がある。しかしながら、保護システム
としてはトラブル発生時に超電導コイルに流れる電流を
確実に保護抵抗に流すことが要求される。サイリスタを
採用する方式では、超電導磁石の保護が必要な時に、サ
イリスタを導通させるための制御機能を持たせることが
要求される。そしてサイリスタを採用する場合の制御機
能は、構成は可能ではあるが保護機能の信頼性を確保す
るためには、外部からの信号に頼らずに保護機能が活き
ることが望ましく、サイリスタによって分流を阻止する
手段は必ずしも保護設備としては適切でないという問題
点がある。
In the circuit structure in which the diode is not connected in the prior art, not only when the trouble of the superconducting coil or the like, which is the original purpose of the protective resistor 4, is encountered, which is usually performed frequently. Even during the degaussing work, the voltage V generated at both ends of the superconducting coil or the like causes a shunt current to the protective resistor, which requires time for the exciting and degaussing work and causes a considerable heat loss in the resistor. Further, in the conventional technology, a diode is arranged in series with a protective resistor in a circuit configuration in which a diode is connected to prevent shunting to the protective resistor during excitation, which is an effective means for solving problems during excitation. However, since the generated voltage is in the opposite direction during degaussing work, the work time is shortened and the diversion prevention function cannot be obtained. For this reason, there is an idea that a thyristor is used instead of a diode to prevent shunting in both directions. However, as a protection system, it is required that the current flowing through the superconducting coil be surely passed through the protection resistor when a trouble occurs. The method using a thyristor is required to have a control function for conducting the thyristor when the superconducting magnet needs to be protected. And the control function when adopting a thyristor can be configured, but in order to ensure the reliability of the protection function, it is desirable that the protection function be utilized without relying on an external signal. There is a problem that the means for doing so are not necessarily appropriate as protective equipment.

【0004】[0004]

【課題を解決するための手段】上記の問題点を解決する
ために励磁や消磁作業時に超電導コイル及び永久電流ス
イッチの両端に発生する電圧よりも高く、かつ超電導コ
イル等のトラブル時に超電導コイル及び永久電流スイッ
チの両端に発生する電圧よりも低い値で回路構成をする
よう、電極をあらかじめ不活性ガス雰囲気中に微小間隔
で配置して構成をした超電導磁石保護回路用スイッチを
提供するものである。
In order to solve the above problems, the voltage is higher than the voltage generated at both ends of the superconducting coil and the permanent current switch at the time of excitation or degaussing work, and when the superconducting coil or the like is in trouble, (EN) Provided is a switch for a superconducting magnet protection circuit, in which electrodes are previously arranged at minute intervals in an inert gas atmosphere so that the circuit is configured with a value lower than the voltage generated across the current switch.

【0005】[0005]

【作用】本発明による保護回路用スイッチは、励磁及び
消磁作業時の保護抵抗体への分流の問題、超電導磁石等
の保護時の回路構成の最適化の問題を解決する手段を提
供するものであり、通常の状態においては、超電導磁石
の保護のための回路は構成されてはいないものの特定電
圧以上になると回路を構成する。これによってこの特定
電圧の値が励磁や消磁時に発生する電圧以上であれば、
励磁や消磁作業時には保護抵抗体への分流を阻止するこ
とが出来、なおかつこの特定電圧の値が超電導コイルや
永久電流スイッチが焼損及び溶断する電圧以下であれ
ば、保護抵抗体への回路を外部から操作することなく、
超電導コイル等がトラブル時に放出するエネルギーを利
用して、初期の電気的な回路構成によって電極間に発生
するアーク放電による熱で両電極を溶着させ物理的な回
路構成をなし、その後は回路構成用スイッチでの発熱も
なく放出エネルギーを全て保護抵抗体へ導くことが出
来、励磁または消磁時の分流に伴う問題を解決させるも
のである。
The switch for a protection circuit according to the present invention provides means for solving the problems of shunting current to the protection resistor during excitation and degaussing operations and optimization of the circuit configuration during protection of superconducting magnets and the like. However, in a normal state, a circuit for protecting the superconducting magnet is not formed, but the circuit is formed when the voltage exceeds a specific voltage. As a result, if the value of this specific voltage is greater than the voltage generated during excitation or demagnetization,
When exciting or degaussing work, it is possible to prevent shunting to the protective resistor, and if the value of this specific voltage is less than the voltage at which the superconducting coil or the permanent current switch burns or melts, the circuit to the protective resistor is externally connected. Without operating from
Utilizing the energy released by the superconducting coil etc. in case of trouble, both electrodes are welded by the heat generated by the arc discharge generated between the electrodes in the initial electrical circuit configuration to form a physical circuit configuration. It is possible to guide all the released energy to the protective resistor without generating heat in the switch, and to solve the problems associated with the shunt current during excitation or demagnetization.

【0006】[0006]

【実施例】図1は本発明の超電導磁石保護回路用スイッ
チの構成図、図2は本発明の回路図である。1は超電導
コイル、2は永久電流スイッチ、3は電流リード線、4
は保護抵抗体、5は超電導磁石保護回路用スイッチ、6
は励磁用の電源、7は接続端子、8は電極、10は不活
性ガス、11は不活性ガス封入用容器である。図2で本
発明の機構を説明する。超電導磁石保護回路用スイッチ
5は励磁や消磁作業時に超電導コイル1の両端に発生す
る電圧では開いている状態であるので超電導コイル1、
永久電流スイッチ2と保護抵抗体4は回路構成されず、
保護抵抗体4への分流は両作業時とも発生しない。した
がって分流によるロスをなくす事ができ作業時間の短縮
が図られる。また超電導磁石保護回路用スイッチ5は超
電導コイル1のクエンチや永久電流スイッチ2のトラブ
ル時に超電導コイル1の両端に発生する電圧ではすでに
閉じた状態になっており、超電導コイル1、永久電流ス
イッチ2と保護抵抗体4は回路構成される。そして超電
導磁石に強力な磁場として蓄えられていたエネルギーを
保護抵抗体4で消費する事ができる。次に図1で超電導
磁石保護回路用スイッチ内部の機構を説明する。電極の
材質としてはタングステン、ニッケル鉄合金等導電性材
料であればなんでも良い。また封入ガスとしてはネオ
ン、ヘリウム等の不活性ガス10を使用する。超電導コ
イル1のクエンチや永久電流スイッチ2のトラブル発生
時には、超電導コイル1や永久電流スイッチ2の両端に
発生する電圧により、電極間でアーク放電が発生し、そ
のアークによって保護回路用スイッチ5が電気的に閉状
態となる。その後超電導磁石保護回路用スイッチ5はア
ーク熱により電極8が溶解し始め、最終的には両電極8
が溶着し、電気的な閉状態から機械的な閉状態へと移行
する。そして機械的な閉状態後はアーク放電がなくなる
ため超電導磁石保護回路用スイッチ5での熱は発生しな
くなる。この電気的な回路構成から機械的な回路構成へ
の移行時間は電極の配置,両電極に使用する材料の組み
合わせ,電極の一部分に電極より融点の低い材料の埋め
込み方によりコントロールが可能である。
1 is a block diagram of a switch for a superconducting magnet protection circuit of the present invention, and FIG. 2 is a circuit diagram of the present invention. 1 is a superconducting coil, 2 is a permanent current switch, 3 is a current lead wire, 4
Is a protective resistor, 5 is a switch for a superconducting magnet protection circuit, 6
Is a power source for excitation, 7 is a connection terminal, 8 is an electrode, 10 is an inert gas, and 11 is an inert gas filling container. The mechanism of the present invention will be described with reference to FIG. Since the superconducting magnet protection circuit switch 5 is in the open state at the voltage generated at both ends of the superconducting coil 1 during the excitation or degaussing work, the superconducting coil 1,
The permanent current switch 2 and the protective resistor 4 do not have a circuit configuration,
The diversion to the protective resistor 4 does not occur in both works. Therefore, the loss due to the shunt can be eliminated, and the working time can be shortened. The switch 5 for the superconducting magnet protection circuit is already closed by the voltage generated across the superconducting coil 1 when the superconducting coil 1 is quenched or the permanent current switch 2 is in trouble. The protective resistor 4 has a circuit configuration. The energy stored as a strong magnetic field in the superconducting magnet can be consumed by the protective resistor 4. Next, the mechanism inside the switch for the superconducting magnet protection circuit will be described with reference to FIG. The material of the electrodes may be any conductive material such as tungsten or nickel-iron alloy. Further, as the filling gas, an inert gas 10 such as neon or helium is used. When a quench occurs in the superconducting coil 1 or a trouble occurs in the persistent current switch 2, an arc discharge occurs between the electrodes due to the voltage generated at both ends of the superconducting coil 1 or the persistent current switch 2, and the arc causes the protection circuit switch 5 to be electrically activated. Will be closed. After that, in the switch 5 for the superconducting magnet protection circuit, the electrodes 8 start to melt due to arc heat, and finally both electrodes 8
Are welded, and the electrical closed state is changed to the mechanical closed state. Then, after the mechanically closed state, the arc discharge disappears and the heat is not generated in the switch 5 for the superconducting magnet protection circuit. The transition time from this electrical circuit configuration to the mechanical circuit configuration can be controlled by the arrangement of electrodes, the combination of materials used for both electrodes, and the method of filling a part of the electrodes with a material having a lower melting point than the electrodes.

【0007】[0007]

【発明の効果】本発明による保護回路用スイッチを超電
導磁石や永久電流スイッチを焼損や溶断から保護する目
的の保護システムに組み込んだ場合、次のような効果を
有している。 1.励磁や消磁作業時に保護抵抗器への分流を阻止する
ことが出来、分流による問題を解決することができる。 2.励磁や消磁の作業時間の短縮を図ることができる。 3.保護抵抗体の本来の役目である超電導コイル等のト
ラブル時のみ電流が流れるので保護抵抗器の小型化を図
ることができる。 4.超電導磁石保護回路用スイッチの開閉用の制御回路
が不要となる。 5.超電導磁石保護回路用スイッチでの発熱量抑えるこ
とができるため、放熱板の必要がなく小型化を図ること
ができる。 6.超電導磁石保護回路用スイッチの小型化で超電導磁
石の一部品として常温部の容易に交換できる位置に組み
込むことができる。 7.超電導磁石の保護システムを改善していく中で、本
発明の超電導磁石保護回路用スイッチを導入することに
よる改善効果は大きい。
When the switch for a protection circuit according to the present invention is incorporated into a protection system for the purpose of protecting a superconducting magnet or a permanent current switch from burning or fusing, it has the following effects. 1. It is possible to prevent shunting to the protective resistor during excitation or degaussing work, and it is possible to solve problems due to shunting. 2. It is possible to shorten the work time for excitation and demagnetization. 3. Since the current flows only when a trouble occurs in the superconducting coil or the like, which is the original function of the protective resistor, the protective resistor can be downsized. 4. A control circuit for opening and closing the switch for the superconducting magnet protection circuit is unnecessary. 5. Since the amount of heat generated by the switch for the superconducting magnet protection circuit can be suppressed, there is no need for a heat dissipation plate, and the size can be reduced. 6. The miniaturization of the switch for the superconducting magnet protection circuit enables it to be installed as a part of the superconducting magnet at a position where it can be easily replaced in the room temperature part. 7. While improving the protection system of the superconducting magnet, the improvement effect by introducing the switch for the superconducting magnet protection circuit of the present invention is great.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明における実施例の構成図である。FIG. 1 is a configuration diagram of an embodiment of the present invention.

【図2】本発明における実施例の回路図である。FIG. 2 is a circuit diagram of an embodiment of the present invention.

【図3】従来技術でダイオードが接続されていない場合
の回路図である。
FIG. 3 is a circuit diagram when a diode is not connected in the related art.

【図4】従来技術でダイオードが接続されている場合の
回路図である。
FIG. 4 is a circuit diagram when a diode is connected in the conventional technique.

【符号の説明】[Explanation of symbols]

1 超電導コイル 2 永久電流スイッチ 3 電流リード線 4 保護抵抗体 5 超電導磁石保護回路用スイッチ 6 励磁用の電源 7 接続端子 8 電極 9 ダイオード 10 不活性ガス 11 不活性ガス封入容器 1 superconducting coil 2 permanent current switch 3 current lead wire 4 protective resistor 5 switch for superconducting magnet protection circuit 6 power supply for excitation 7 connection terminal 8 electrode 9 diode 10 inert gas 11 inert gas sealed container

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 超電導コイルのクエンチまたは永久電流
スイッチのトラブル発生時に、該超電導コイル及び該永
久電流スイッチを焼損や溶断から保護する目的で常温領
域に設ける保護システムに保護抵抗体と直列に接続する
超電導磁石保護回路用スイッチにおいて、超電導磁石保
護回路用スイッチ内部の電極をあらかじめ不活性ガス中
に微小距離をおいて配置し、保護時には超電導磁石に蓄
えられているエネルギーを利用し、保護の初期には両電
極がアーク放電によって回路を構成し、その後はアーク
放電中にアーク熱によって電極を溶解し両電極を溶着さ
せることで回路を構成する、アーク放電による回路構成
から両電極の溶着による回路構成に移行することを特徴
とする超電導磁石保護回路用スイッチ。
1. When a quench of a superconducting coil or a trouble of a persistent current switch occurs, the superconducting coil and the persistent current switch are connected in series with a protective resistor in a protection system provided in a room temperature region for the purpose of protecting them from burnout or fusing. In the switch for the superconducting magnet protection circuit, the electrodes inside the switch for the superconducting magnet protection circuit are placed in advance in a small distance in an inert gas, and the energy stored in the superconducting magnet is used at the time of protection to ensure the initial protection. Both electrodes form a circuit by arc discharge, and then the circuit is constructed by melting the electrodes and welding both electrodes by arc heat during arc discharge.From the circuit configuration by arc discharge to the circuit configuration by welding of both electrodes Switch for superconducting magnet protection circuit, which is characterized in that
【請求項2】 請求項1の超電導磁石保護回路用スイッ
チにおいて、両電極のうちの一方の電極に他方より融点
の低い材料を用い、溶着を促進させることを特徴とする
請求項1記載の超電導磁石保護回路用スイッチ。
2. The superconducting magnet protection circuit switch according to claim 1, wherein a material having a lower melting point than one of the two electrodes is used to promote welding. Switch for magnet protection circuit.
【請求項3】 請求項1の超電導磁石保護回路用スイッ
チにおいて、両電極のうちの一方の電極の一部に母材よ
り融点の低い材料を埋め込み、溶着を促進させることを
特徴とする請求項1記載の超電導磁石保護回路用スイッ
チ。
3. The switch for a superconducting magnet protection circuit according to claim 1, wherein a material having a melting point lower than that of the base material is embedded in a part of one of the two electrodes to promote welding. 1. A switch for a superconducting magnet protection circuit according to 1.
JP4260573A 1992-09-04 1992-09-04 Superconducting magnet protection circuit switch Expired - Fee Related JP2708678B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP4260573A JP2708678B2 (en) 1992-09-04 1992-09-04 Superconducting magnet protection circuit switch

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP4260573A JP2708678B2 (en) 1992-09-04 1992-09-04 Superconducting magnet protection circuit switch

Publications (2)

Publication Number Publication Date
JPH0685335A true JPH0685335A (en) 1994-03-25
JP2708678B2 JP2708678B2 (en) 1998-02-04

Family

ID=17349831

Family Applications (1)

Application Number Title Priority Date Filing Date
JP4260573A Expired - Fee Related JP2708678B2 (en) 1992-09-04 1992-09-04 Superconducting magnet protection circuit switch

Country Status (1)

Country Link
JP (1) JP2708678B2 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006352146A (en) * 2006-07-10 2006-12-28 Toshiba Corp Superconductive magnet and its protection circuit
WO2015092910A1 (en) * 2013-12-20 2015-06-25 株式会社日立製作所 Superconducting magnet, mri, and nmr

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006352146A (en) * 2006-07-10 2006-12-28 Toshiba Corp Superconductive magnet and its protection circuit
JP4568253B2 (en) * 2006-07-10 2010-10-27 株式会社東芝 Superconducting magnet protection circuit
WO2015092910A1 (en) * 2013-12-20 2015-06-25 株式会社日立製作所 Superconducting magnet, mri, and nmr
JPWO2015092910A1 (en) * 2013-12-20 2017-03-16 株式会社日立製作所 Superconducting magnet, MRI and NMR
US10121955B2 (en) 2013-12-20 2018-11-06 Hitachi, Ltd. Superconducting magnet, MRI, and NMR

Also Published As

Publication number Publication date
JP2708678B2 (en) 1998-02-04

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