Superconducting coil, method for producing same, and superconducting rectangular wire for superconducting coil

Patent metadata

Field	Value
Publication number	US-12211642-B2
Application number	US-202017777563-A
Country	US
Kind code	B2
Filing date	Nov 18, 2020
Priority date	Nov 18, 2019
Publication date	Jan 28, 2025
Grant date	Jan 28, 2025

Abstract

The superconducting coil includes: a winding frame; and at least two superconducting rectangular wire layers provided in such a manner that a superconducting rectangular wire is spirally wound on an outer surface of the frame such that wires adjacent to each other in an axial direction of the frame are arranged side by side and separated, the wire including an NbTi-based or Nb 3 Sn-based wire having a surface coated with copper or copper alloy, in which at least a thermoplastic fusible resin is provided in a separated section between the adjacent wires, and when viewed in a cross section including an axis of the frame, at least one of voids that are partitionable on outer surfaces of a total of three wires and a total of four wires located on the two adjacent layers and adjacent to each other are 4% or less in terms of a void ratio (V1).

First claim

The invention claimed is:

1. A superconducting coil comprising:
a winding frame; and
at least two superconducting rectangular wire layers provided in such a manner that a superconducting rectangular wire is spirally wound on an outer peripheral surface of the winding frame in a substantially circumferential direction of the winding frame such that wires adjacent to each other in an axial direction of the winding frame are arranged side by side and separated from each other, the superconducting rectangular wire including an NbTi-based or Nb 3 Sn-based wire having a surface coated with copper or copper alloy and having a substantially rectangular cross-section, wherein
at least a thermoplastic fusible resin is provided in a separated section between the adjacent wires in the same superconducting rectangular wire layer and provided in a separated section between the adjacent wires that are located respectively in the two superconducting rectangular wire layers adjacent to each other, and
when viewed in a cross section including an axis of the winding frame, at least one of voids that are partitionable on outer surfaces of a total of three superconducting rectangular wires and are partitionable on outer surfaces of a total of four superconducting rectangular wires located on the two adjacent superconducting rectangular wire layers and adjacent to each other are 4% or less in terms of a void ratio (V1), which is an area ratio of the voids occupying the at least two superconducting rectangular wire layers.

2. The superconducting coil according to claim 1 , wherein the voids are partitioned on the outer surfaces of a total of three and a total of four superconducting rectangular wires located on the two adjacent superconducting rectangular wire layers and adjacent to each other when viewed in the cross section including the axis of the winding frame.

3. The superconducting coil according to claim 1 , wherein the superconducting rectangular wire includes a fusible resin layer made of the thermoplastic fusible resin that coats an outer peripheral surface of the wire.

4. The superconducting coil according to claim 3 , wherein the superconducting rectangular wire further includes an insulating resin layer between the outer peripheral surface of the wire and the fusible resin layer.

5. The superconducting coil according to claim 4 , wherein the insulating resin layer is made of one or more selected from a polyvinyl formal resin, a polyamide-imide resin, a polyimide resin, a polyester resin, and a polyurethane resin.

6. The superconducting coil according to claim 4 , wherein an average coating thickness of the insulating resin layer is 0.005 mm or more and 0.100 mm or less.

7. The superconducting coil according to claim 1 , wherein the thermoplastic fusible resin is made of one or more selected from a phenoxy resin, a polyamide resin, and a polyester resin.

8. The superconducting coil according to claim 1 , wherein the wire is a rectangular wire, and a radius of curvature (R 1 ) at a corner portion of the wire is 0.1 mm or more and 0.4 mm or less.

9. The superconducting coil according to claim 1 , wherein the wire is a rectangular wire, and a radius of curvature (R 1 ) at a corner portion of the wire satisfies Expression (1) and Expression (2) indicated below;

[

Math
.

1

]

0
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R
⁢
1

≦

R
⁢

1
max

Expression
⁢

(
1
)

R
⁢

1
max

[
mm
]

=

A
×

(

Cross
-
sectional
⁢

width
⁢

of
⁢

wire

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×

(

Cross
-
sectional
⁢

thickness
⁢

of
⁢

wire

)

4
-
π

Expression
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(
2
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A is 0.06 in Expression (2).

10. The superconducting rectangular wire according to claim 9 , further comprising an insulating resin layer made of an insulating resin between the outer peripheral surface of the wire and the fusible resin layer.

11. The superconducting rectangular

Assignees

• Furukawa Electric Co Ltd

Inventors

• Kim Yonghoon
• Ii Hideki
• Sato Takumi
• Asami Daisuke
• Sugimoto Masahiro
• Tsubouchi Hirokazu

Classifications

• H01F41/048

  Superconductive coils · CPC title

• Y10S505/701

  Coated or thin film device, i.e. active or passive · CPC title

• Y10S505/739

  Molding, coating, shaping, or casting of superconducting material · CPC title

• Y10S505/704

  Wire, fiber, or cable · CPC title

• Y02E40/60

  Superconducting electric elements or equipment; Power systems integrating superconducting elements or equipment · CPC title