JP2019062005A - High temperature superconducting coil device and high temperature superconducting magnet device - Google Patents

Abstract

To provide a high temperature superconducting coil device capable of preventing local thermal runaway inside without deteriorating critical current characteristics of a high temperature superconducting wire.SOLUTION: A high temperature superconducting coil device is a high temperature superconducting coil device in which tape-shaped high temperature superconducting wires 1, 2 are wound. At least at one point of a winding exceeding at least one turn, the high temperature superconducting wires 1, 2 are wound a plurality of times. The plurality of high temperature superconducting wires 1, 2 are electrically connected by direct contact.SELECTED DRAWING: Figure 4

Description

  The embodiments of the present invention relate to a high temperature superconducting coil device in which a tape-shaped high temperature superconducting wire is wound and a high temperature superconducting magnet device using the same.

  The superconducting wire has a current, a temperature, a range of a magnetic field capable of maintaining a superconducting state, a so-called critical current, a critical temperature, and a critical magnetic field. Therefore, even if the electrical resistance is almost zero, the current can not flow infinitely, and when any one of the critical values is exceeded, a transition to a normal conducting state, ie, quenching occurs.

  Such joule heat generation in the normal conduction transition region due to the quenching instantaneously causes thermal runaway of the superconducting coil, and in the worst case, there is a risk of burnout. Therefore, protection techniques against quench are essential.

  As a prior art regarding a quench protection, there exists a method of connecting a protection resistance in parallel with a superconducting coil, for example. This method is a method of detecting a rise in coil voltage or a temperature rise generated by transitioning to a normal conduction state, and using this detection result as a trigger to shut off the excitation power supply. After the power is turned off, a closed circuit of the superconducting coil and the protective resistor is formed, so that the stored energy of the superconducting coil is consumed by Joule heating of the protective resistor disposed at the room temperature portion, and the current flowing in the superconducting coil can be attenuated.

Such superconducting wire used for superconducting coils, for example, _{Bi 2 Sr 2 Ca 2 Cu 3} O 10 + x _wire, there is a high-temperature superconducting wire such RE ₁ B ₂ C 3 _{O 7} wire rod. Here, “RE” is a rare earth element, “B” is barium (Ba), “C” is copper (Cu), and “O” is oxygen (O). A superconducting coil using a high temperature superconducting wire has a high critical current density even at a high temperature such as 20 K to 50 K as compared with a conventional low temperature superconducting wire such as NbTi, so high current density operation at high temperature is possible.

  However, when quenching occurs during high current density operation, the expansion of the normal conduction transition region is slow in the temperature range of 20 K to 50 K because the specific heat is larger than the operating temperature of the superconducting magnet using a low temperature superconducting wire. In addition, since the heat generation density also increases when the high current density operation is performed, in the above-described quench protection method of the prior art, thermal runaway occurs locally before detection and burnout occurs.

  Therefore, for example, Patent Document 1 proposes a technique in which a high temperature superconducting wire is bonded to a winding portion having a severe empirical magnetic field and a low critical current inside the high temperature superconducting coil to partially overlap two wires. According to this technique, current can be diverted to the bonded high temperature superconducting wire even if the current value or temperature that normally quenches is reached. Therefore, the current sharing of the high-temperature superconducting wire per sheet is about half, and by suppressing the Joule heat generation, thermal runaway can be prevented in advance. In addition, by partially bonding, it is possible to minimize the reduction in current density.

JP, 2006-313923, A

  By the way, in the said patent document 1, the connection method of 0.01 microhm level is proposed by the lap | wrap length of 100 mm, for example as a bonding method which bonds a high temperature superconducting wire together, Usually, a solder connection is used as a connection method of resistance of this order. There is. Other bonding methods include diffusion bonding, welding, ultrasonic bonding and the like.

However, since the two high temperature superconducting wires 1 and 2 connected as shown in FIG. 10 are integrated through the bonding layer 3, bending strain ε = (t ′ / 2) when coiled / R is twice as large as in the case of one sheet. Here, R represents an average radius of curvature, and t ′ represents the sum t ′ = t ₁ + t ₂ + t ₃ of the thicknesses of the two high temperature superconducting wires 1 and 2 including the thickness of the bonding layer 3. Further, t ₁ and t ₂ indicate the thicknesses of the two high temperature superconducting wires 1 and 2, and t ₃ indicates the thickness of the bonding layer 3.

  Furthermore, since the high-temperature superconducting wires 1 and 2 in the form of two sheets have high rigidity in the thickness direction of the wire, it is difficult to wind around the circular winding portion with uniform curvature during winding. Therefore, when bending with an uneven curvature, the allowable bending strain is locally exceeded, and the critical current characteristics of the high temperature superconducting wires 1 and 2 deteriorate with one or two sheets. As a result, not only the thermal runaway due to the commutation of the current, which is the initial objective, can not be prevented, but also the thermal runaway due to Joule heat of the deteriorated portion may cause burnout.

  The problem to be solved by the present embodiment is to provide a high temperature superconducting coil device and a high temperature superconducting magnet device capable of preventing local thermal runaway inside without deteriorating the critical current characteristics of the high temperature superconducting wire. It is in.

  In order to solve the above problems, the high temperature superconducting coil device according to the present embodiment is a high temperature superconducting coil device in which a tape-shaped high temperature superconducting wire is wound, and at least one place of a winding portion exceeding at least one turn. A plurality of the high temperature superconducting wires are wound, and the plurality of high temperature superconducting wires are electrically connected by direct contact.

  The high temperature superconducting magnet apparatus according to the present embodiment is characterized by including the high temperature superconducting coil apparatus according to the present embodiment.

  According to this embodiment, it is possible to prevent local thermal runaway inside the high temperature superconducting coil device without deteriorating the critical current characteristics of the high temperature superconducting wire.

It is a block diagram which shows an example of the high temperature superconducting wire used for the high temperature superconducting coil apparatus of each embodiment. (A) is a schematic perspective view which shows the pancake coil of an example of the high temperature superconducting coil apparatus of each embodiment, (b) is a schematic sectional drawing of (a), (c) is an expanded sectional view of (b). It is a sectional view showing the high temperature superconducting coil device of a 1st embodiment. It is the figure which looked at the high temperature superconducting wire immediately after winding-up in 1st Embodiment from the coil upper surface. It is a graph which shows the relationship between the number of turns of the winding part co-wound in 1st Embodiment, and the voltage per unit length. It is an expanded sectional view which shows the part by which the 1st high temperature superconducting wire and the 2nd high temperature superconducting wire are co-wound in 2nd Embodiment. It is sectional drawing which shows the high temperature superconducting coil apparatus of 3rd Embodiment. It is sectional drawing which shows the high temperature superconducting coil apparatus of 4th Embodiment. It is a longitudinal cross-sectional view which shows an example of the high temperature superconducting magnet apparatus which applied the high temperature superconducting coil apparatus of each embodiment. It is the figure which looked at the high temperature superconducting wire immediately after winding-up in a prior art example from the coil upper surface.

  Hereinafter, the high temperature superconducting coil device and the high temperature superconducting magnet device according to the present embodiment will be described with reference to the drawings.

(High temperature superconducting wire)
FIG. 1: is a block diagram which shows an example of the high temperature superconducting wire (superconducting tape wire) used for the high temperature superconducting coil apparatus of each embodiment.

  The same or corresponding parts as in the conventional example will be described with the same reference numerals. In the following description, when the first high-temperature superconducting wire and the second high-temperature superconducting wire are described separately, they are denoted by reference numerals 1 and 2 respectively. When the first high-temperature superconducting wire and the second high-temperature superconducting wire are collectively described, only the reference numeral 1 is simply given.

  As shown in FIG. 1, the high-temperature superconducting wire 1 is entirely formed in a tape shape. The high temperature superconducting wire 1 has at least a tape substrate 4, an intermediate layer 5 and a superconducting layer 6, and both surfaces thereof are covered with a stabilization layer 7.

  The high temperature superconducting wire 1 can also be provided with an orientation layer 8 between the tape substrate 4 and the intermediate layer 5 and a protective layer 9 between the superconducting layer 6 and the stabilization layer 7 as necessary.

  The tape substrate 4 is formed of, for example, a material such as stainless steel, a nickel alloy such as hastelloy, or a silver alloy.

  The intermediate layer 5 is a diffusion preventing layer and made of, for example, materials such as cerium oxide, yttria-stabilized zirconia (YSZ), magnesium oxide, yttrium oxide, ytterbium oxide, barium zirconia and the like, and is formed on the tape substrate 4.

The superconducting layer 6 is made of, for example, a superconductor thin film having a composition of RE123 system (RE ₁ B ₂ C ₃ O ₇ or the like). In addition, "RE" of "RE ₁ B ₂ C ₃ O ₇ " is at least one of rare earth elements (eg, neodymium (Nd), gadolinium (Gd), holmium (Ho), samarium (Sm), etc.) and yttrium element. “B” means barium (Ba), “C” means copper (Cu) and “O” means oxygen (O).

  The stabilization layer 7 is provided for the purpose of preventing the superconducting layer 6 from burning when electricity flows excessively to the superconducting layer 6, and is made of silver or the like having high conductivity.

  The orientation layer 8 is provided for the purpose of orienting and forming the intermediate layer 5 on the tape substrate 4 and is made of magnesium oxide (MgO) or the like. The alignment layer 8 can be omitted when using an oriented substrate.

  The protective layer 9 is provided for the purpose of preventing the superconducting layer 6 from deteriorating due to contact with moisture in the air, and is made of silver or the like. The protective layer 9 also plays a role of preventing the superconducting layer 6 from burning when electricity flows excessively to the superconducting layer 6.

  The tape width w of the high temperature superconducting wire 1 composed of such multilayers is, for example, 4 to 12 mm, and the tape thickness t is 0.1 to 0.2 mm. Further, the high temperature superconducting wire 1 is excellent in mechanical strength in the longitudinal direction while being characterized by being vulnerable to tensile stress (peeling stress) in the direction perpendicular to the tape surface.

  Furthermore, an insulation coated superconducting tape wire may be used in which the high temperature superconducting wire 1 is covered with an insulating material such as polyimide or polyimide amide.

(High temperature superconducting coil device)
Fig.2 (a) is a schematic perspective view which shows the pancake coil of an example of the high temperature superconducting coil apparatus of each embodiment, FIG.2 (b) is a schematic sectional drawing of Fig.2 (a), FIG.2 (c) is FIG. It is an expanded sectional view of (b).

  As shown in FIGS. 2 (b) and 2 (c), the high temperature superconducting wire 1 is superposed on the insulating tape wire 11 and made of an insulating material such as glass fiber reinforced plastic (FRP) or reinforced PTFE (polytetrafluoroethylene). A so-called pancake-shaped winding portion 13 wound in a spiral shape is formed around the winding frame 12. In addition, by forming insulating layers 14 on both the upper and lower surfaces of the winding portion 13 as necessary, a so-called pancake-shaped high-temperature superconducting coil device 10 as shown in FIG. 2A, ie, a pancake coil is formed. Ru.

First Embodiment
(Constitution)
FIG. 3 is a cross-sectional view showing the high-temperature superconducting coil device of the first embodiment. FIG. 4 is a view of the high-temperature superconducting wire immediately after winding in the first embodiment as viewed from the top of the coil. FIG. 5 is a graph showing the relationship between the number of turns of the winding part to be co-wound and the voltage per unit length in the first embodiment.

  In the high temperature superconducting coil device 10 of the present embodiment, as shown in FIG. 3, the first high temperature superconducting wire 1 wound around the outer periphery of the winding frame 12 is the first in the winding portion 13 exceeding at least one turn. The second high temperature superconducting wire 2 is co-wound adjacent to the high temperature superconducting wire 1. The first high temperature superconducting wire 1 and the second high temperature superconducting wire 2 are not fixed to each other via a bonding layer such as solder as in the prior art, and are electrically connected by direct contact. The second high temperature superconducting wire 2 is the same as the multilayer structure of the high temperature superconducting wire 1, the tape width w, and the thickness t.

  Here, the windings 13 exceeding at least one turn to be co-wound may be provided in at least one place depending on the design of the quench protection, and in the present embodiment, for example, in a coil having 100 turns in total. It is co-wound in two places, 10 to 30 turns and 90 to 100 turns.

The resistance R _joint of the electrical connection per unit length by the direct contact between the first high temperature superconducting wire 1 and the second high temperature superconducting wire 2 is approximately 0.1 to 0.1 of the ripple current of the excitation power supply. It is a few percent. Thus, in order to obtain the effect of commutation, the commutation ratio of the first high temperature superconducting wire 1 to the second high temperature superconducting wire 2 needs to be at least 1/1000 or more.

  On the other hand, since the voltage per unit length generated in the high temperature superconducting wires 1 and 2 before and after quenching is about 1 μV / cm, the resistance value is a value calculated by dividing 1 μV / cm by the operating current value. .

Therefore, the resistance R _joint of electrical connection per unit length by direct contact between the first high temperature superconducting wire 1 and the second high temperature superconducting wire 2 is operated at a voltage of 1 μV / cm per unit length. It is preferable to set the resistance value to 1000 times or less of the resistance value calculated by dividing by the current value.

As an example, when the operating current value is 100 A, the resistance value per unit length generated in the high temperature superconducting wires 1 and 2 before and after quenching is 10 ⁻⁸ Ω / cm, so that the first high temperature superconducting The resistance R _joint of the electrical connection per unit length by direct contact between the wire 1 and the second high temperature superconducting wire 2 may be set to 10 ⁻⁵ Ω / cm or less.

Further, the second high temperature superconducting wire 2 is (Bi, Pb) ₂ Ca ₂ Sr in addition to the high temperature superconducting wire using the RE ₁ B ₂ C ₃ O ₇ as the superconducting layer, similarly to the first high temperature superconducting wire 1 A superconducting tape using a so-called bismuth-based high temperature superconducting material having a composition such as ₁ Cu ₂ O _{10 + x} , (Bi, Pb) ₂ Ca ₂ Sr ₂ Cu ₃ O _{10 + x} , (Bi, Pb) ₂ Ca ₂ Sr ₃ Cu ₄ O 10+ _x It may be

  Such a bismuth-based superconducting tape is a so-called multicore tape wire material in which a plurality of filamentous bismuth-based high-temperature superconducting materials are injected into a silver base material, and depending on the design, a high-strength metal tape for reinforcement. Is attached.

(Operation)
As described above, in the conventional example, since the two high temperature superconducting wires 1 and 2 are integrated by the bonding layer 3 such as solder, the thickness is twice that in the case of one sheet, and coiled The bending strain is also twice as large as that of one sheet. And since the rigidity in the wire thickness direction becomes high, it becomes difficult to wind around the circular winding portion 13 with uniform curvature during winding. Therefore, if bending is performed with non-uniform curvature, the allowable bending strain is locally exceeded, and the critical current characteristics of the high temperature superconducting wires 1 and 2 deteriorate in one or two sheets. As a result, not only the thermal runaway due to the commutation of the current which is initially aimed can not be prevented, but also the thermal runaway and burnout may occur due to Joule heat of the deteriorated portion.

  On the other hand, in the present embodiment, the first high temperature superconducting wire 1 and the second high temperature superconducting wire 2 are not integrated by the bonding layer 3 such as solder, but are electrically connected by direct contact. There is. Therefore, the second high temperature superconducting wire 2 can slide in the direction of the arrow shown in FIG. 4 when winding.

Therefore, in this embodiment, the second high-temperature superconducting wire 2, the first high-temperature superconducting wire 1 and likewise can be bent in the one sheet bending strain _{ε = (t 2/2)} / R. Moreover, since it can wind up to round winding part 13 with uniform curvature like the 1st high temperature superconducting wire 1 at the time of winding, it is 1st high temperature superconducting wire 1 and the 2nd high temperature superconducting wire 2 There is no deterioration of the critical current characteristics. Then, when the first high temperature superconducting wire 1 is quenched, commutation of current to the second high temperature superconducting wire 2 is enabled, and the Joule heat is suppressed, locally in the high temperature superconducting coil device 10 Thermal runaway can be prevented in advance.

  Specifically, in the present embodiment, for example, in a coil having a total number of turns (total number of turns N) of 100 turns, the second high temperature superconducting wire 1 is disposed at two positions of 10 to 30 turns and 90 to 100 turns. The high temperature superconducting wire 2 is co-wound. As shown in FIG. 5, when the first high temperature superconducting wire 1 is quenched, the voltage per unit length generated in the first high temperature superconducting wire 1 at two points of 10 to 30 turns and 90 to 100 turns. The waveform V (V / cm) changes from a waveform shown by a solid line to a waveform shown by a broken line. This indicates that the voltage V per unit length is reduced by the current being reliably diverted to the second high temperature superconducting wire 2 when the first high temperature superconducting wire 1 is quenched. .

(Effect)
As described above, according to the present embodiment, since the first high temperature superconducting wire 1 and the second high temperature superconducting wire 2 are electrically connected by direct contact, the first high temperature superconducting wire 1 and the second high temperature superconducting wire 2 are electrically connected to each other. It is possible to prevent local thermal runaway inside the high temperature superconducting coil device 10 without deteriorating the critical current characteristics of the critical current characteristics of the high temperature superconducting wire 2.

  In the present embodiment, an example of a pancake coil of a so-called pancake shape, which is wound concentrically as the high temperature superconducting coil device 10, has been described. However, the present invention is not limited thereto. The present invention can also be applied to a so-called double pancake type high temperature superconducting coil device in which two laminated layers are formed and the high temperature superconducting wire is axially transferred at the innermost circumference. In addition, three or more pancake coils 10 may be stacked in the central axis direction. Furthermore, the planar shape of the coil is not limited to a circular shape, and the same effect can be obtained with a non-circular coil shape such as a D shape, an elliptical shape, a racetrack shape, or a three-dimensional shape.

Second Embodiment
(Constitution)
FIG. 6 is an enlarged sectional view showing a portion where the first and second high temperature superconducting wires are co-wound in the second embodiment. The second embodiment is a modification of the first embodiment. In the second embodiment, the same or corresponding parts as in the first embodiment are given the same reference numerals, and redundant explanations will be omitted, and only different configurations and actions will be described. The same applies to the other embodiments.

  As shown in FIG. 6, in the high temperature superconducting coil device 10 of the present embodiment, the superconducting layer 15 of the first high temperature superconducting wire 1 and the superconducting layer 16 of the second high temperature superconducting wire 2 are provided close to one side. .

  The high temperature superconducting coil device 10 of the present embodiment includes a tape surface on the side near the superconducting layer 15 of the first high temperature superconducting wire 1 and a tape surface on the side near the superconducting layer 16 of the second high temperature superconducting wire 2. Are configured adjacent to each other.

(Operation)
In the embodiment configured as described above, the first high temperature superconducting wire 1 and the second high temperature superconducting wire 2 are arranged such that the tape surfaces closer to the superconducting layers 15 and 16 are adjacent to each other. Therefore, compared to the case where both high temperature superconducting wires 1 and 2 face the tape surface on the side close to the tape substrate 4, the resistance of the electrical connection can be made lower.

(Effect)
As described above, according to the present embodiment, since the resistance of the electrical connection between the first high temperature superconducting wire 1 and the second high temperature superconducting wire 2 can be further lowered, the first high temperature superconducting wire 1 is At the time of quenching, commutation of current to the second high temperature superconducting wire 2 is facilitated, and local thermal runaway inside the high temperature superconducting coil device 10 is more reliably prevented in comparison with the first embodiment. It will be possible to

Third Embodiment
(Constitution)
FIG. 7 is a cross-sectional view showing the high-temperature superconducting coil device of the third embodiment.

  As shown in FIG. 7, the high temperature superconducting coil device 10 of the present embodiment is configured by electrically connecting the tape-shaped metal wires 17 by direct contact adjacent to the second high temperature superconducting wires 2. . As a material of the metal wire rod 17, a pure metal such as copper, gold, silver, or indium, or an alloy such as stainless steel, a copper alloy, or a silver alloy can be used.

(Operation)
In the embodiment configured as described above, since the tape-shaped metal wire 17 is electrically connected by direct contact adjacent to the second high temperature superconducting wire 2, the first high temperature superconducting wire 1 is When quenching is performed, the region where current can be diverted is expanded, and the heat capacity of the winding portion 13 for one turn is increased, so that the temperature rise due to Joule heat can be suppressed.

(Effect)
As described above, according to the present embodiment, when the first high temperature superconducting wire 1 is quenched, the area where current can be diverted is expanded, and the heat capacity of the winding portion 13 for one turn is increased. Since a temperature rise due to heat generation can be suppressed, it is possible to prevent local thermal runaway in the high-temperature superconducting coil device 10 more reliably than in the first and second embodiments.

(Modification)
In the high temperature superconducting coil device 10 of the present embodiment, the tape-shaped metal wire 17 is electrically connected to the second high temperature superconducting wire 2 by direct contact, but this metal wire 17 is a first high temperature The superconducting wire 1 may be electrically connected by direct contact. The metal wire 17 may be electrically connected to both the second high temperature superconducting wire 2 and the first high temperature superconducting wire 1 by direct contact. In short, the metal wire 17 may be electrically connected to at least one of the second high temperature superconducting wire 2 and the first high temperature superconducting wire 1 by direct contact.

Fourth Embodiment
(Constitution)
FIG. 8 is a cross-sectional view showing the high-temperature superconducting coil device of the fourth embodiment.

  As shown in FIG. 8, in the high temperature superconducting coil device 10 of the present embodiment, the second high temperature superconducting wire 2 is a tape than the second high temperature superconducting wire 2 described in the first to third embodiments. The thickness is thin.

  That is, although the second high-temperature superconducting wire 2 described in the first to third embodiments has the same tape thickness as the first high-temperature superconducting wire 1, the second high-temperature superconducting wire of this embodiment The wire 2 is formed to have a thinner tape thickness than the first high temperature superconducting wire 1.

  For example, assuming that the tape thickness of the first high-temperature superconducting wire 1 and the second high-temperature superconducting wire 2 described in the first to third embodiments is 0.17 mm, the second high-temperature superconductor of this embodiment is The tape thickness of the wire 2 is 0.1 mm.

(Operation)
In this embodiment configured as described above, the tape thickness of the second high temperature superconducting wire 2 is thinner than that of the first high temperature superconducting wire 1, so that the second embodiment can be compared with the first to third embodiments. Although the heat capacity of the winding portion 13 of one turn decreases, the cross-sectional area of the winding portion 13 can be made smaller.

(Effect)
As described above, according to the present embodiment, although the heat capacity of the winding portion 13 of one turn is reduced as compared with the first to third embodiments, the cross-sectional area of the winding portion 13 can be further reduced. Therefore, it is possible to suppress the decrease in current density due to the co-winding effect.

(Modification)
The second high-temperature superconducting wire 2 of the present embodiment has a tape thickness t larger than that of the first high-temperature superconducting wire 1 and the second high-temperature superconducting wire 2 described in the first to third embodiments. Although thinly formed, the second high temperature superconducting wire 2 may be formed to have a narrower tape width w than the second high temperature superconducting wire 2 described in the first to third embodiments. As described above, the first high-temperature superconducting wire 1 and the second high-temperature superconducting wire 2 may not necessarily have the same tape thickness t or tape width w.

(High temperature superconducting magnet device)
FIG. 9 is a longitudinal sectional view showing an example of a high temperature superconducting magnet device to which the high temperature superconducting coil device of each embodiment is applied.

  As shown in FIG. 9, in the high-temperature superconducting magnet device 20, the high-temperature superconducting coil device 10 of any of the above-described embodiments is accommodated in a vacuum vessel 21. The high temperature superconducting coil device 10 is supported by a support member (not shown).

  The refrigerator 22 is thermally connected to the high temperature superconducting coil device 10 through the heat transfer plate 23 in the vacuum vessel 21. Two current introduction terminals 24, 24 are provided outside the vacuum vessel 21. One end of a current lead 25 is connected to each of the two current introduction terminals 24, and the other end of the current lead 25 is connected to the high temperature superconducting coil device 10. The current leads 25, 25 are thermally connected via the thermal anchor 26 to the cooling end of the refrigerator 22.

  Therefore, thermal runaway inside high temperature superconducting coil device 10 can be prevented beforehand by housing high temperature superconducting coil device 10 of each embodiment in high temperature superconducting magnet device 20 configured in this way.

(Other embodiments)
Although the embodiments of the present invention have been described, this embodiment is presented as an example and is not intended to limit the scope of the invention. This embodiment can be implemented in other various forms, and various omissions, replacements, changes, and combinations can be made without departing from the scope of the invention. This embodiment and its modifications are included in the invention described in the claims and the equivalents thereof as well as included in the scope and the gist of the invention.

  In the high temperature superconducting coil device 10 of each of the above embodiments, an example in which two high temperature superconducting wires, ie, the first high temperature superconducting wire 1 and the second high temperature superconducting wire 2 are co-wound, has been described. For example, three or more tape-shaped high temperature superconducting wires may be electrically connected by direct contact.

  In the high temperature superconducting coil device 10 of the first embodiment, an example in which the two high temperature superconducting wires 1 and 2 are co-wound at two points of the winding portion 13 has been described, but not limited thereto. The two high temperature superconducting wires 1 and 2 may be co-wound at at least one place.

  Furthermore, the features of the high temperature superconducting coil device 10 of each of the above embodiments can be combined and implemented.

  DESCRIPTION OF SYMBOLS 1 ... 1st high temperature superconducting wire material, 2 ... 2nd high temperature superconducting wire material, 3 ... joining layer, 4 ... tape substrate, 5 ... intermediate layer, 6 ... superconducting layer, 7 ... stabilization layer, 8 ... orientation layer, 9 ... Protective layer, 10: High temperature superconducting coil device (pancake coil), 11: Insulating tape wire, 12: Winding frame, 13: Winding portion, 14: Insulating layer, 15, 16: Superconducting layer, 17: Metal wire, DESCRIPTION OF SYMBOLS 20 ... High temperature superconducting magnet apparatus, 21 ... Vacuum vessel, 22 ... Refrigerator, 23 ... Heat-transfer plate, 24 ... Current introduction terminal, 25 ... Current lead, 26 ... Thermal anchor

Claims (9)

A high temperature superconducting coil device in which a tape-shaped high temperature superconducting wire is wound,
A high temperature superconducting coil characterized in that a plurality of the high temperature superconducting wires are wound in at least one place of a winding part exceeding at least one turn, and the plurality of high temperature superconducting wires are electrically connected in direct contact. apparatus.   The high temperature superconducting coil device according to claim 1, wherein the plurality of high temperature superconducting wires comprise a first high temperature superconducting wire and a second high temperature superconducting wire.   The high temperature superconducting coil device according to claim 2, wherein the first high temperature superconducting wire and the second high temperature superconducting wire are co-wound.   The high temperature superconducting coil device according to claim 2 or 3, wherein the first high temperature superconducting wire and the second high temperature superconducting wire are wound around an outer periphery of a winding frame together with an insulating material.   The first high temperature superconducting wire and the second high temperature superconducting wire are respectively provided with a superconducting layer close to one side, and the first high temperature superconducting wire and the second high temperature superconducting wire are close to the superconducting layer. The high temperature superconducting coil device according to any one of claims 2 to 4, wherein the side surfaces are adjacent to each other.   The tape-shaped metal wire is electrically connected to at least one of the first high-temperature superconducting wire and the second high-temperature superconducting wire by direct contact. The high-temperature superconducting coil device according to item 2.   The high-temperature superconducting coil device according to any one of claims 2 to 6, wherein the thickness of the second high-temperature superconducting wire is smaller than that of the first high-temperature superconducting wire.   The resistance of the electrical connection per unit length by direct contact between the first high temperature superconducting wire and the second high temperature superconducting wire divides the voltage 1 μV / cm per unit length by the operating current value The high-temperature superconducting coil device according to any one of claims 2 to 7, wherein the resistance value is 1,000 times or less of the resistance value calculated.   A high temperature superconducting magnet apparatus comprising the high temperature superconducting coil apparatus according to any one of claims 1 to 8.

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