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.sub.3Sn-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).

A polymer composition for impregnating a high temperature superconductor (HTS) coil, the composition comprising: a polymer resin, a plurality of particles of a first filler material, and a plurality of particles of a second filler material; wherein the median particle size of the second filler material is less than the median particle size of the first filler material. The polymer composition may be used to prepare a polymer impregnated HTS coil having a predetermined turn-to-turn spacing. A property of the polymer composition may also be modified, for example, the coefficient of thermal contraction and/or resistivity of the composition. Also disclosed is a polymer impregnated HTS coil and a method for preparing the coil.

It is an object to provide a method for producing a substrate for epitaxial growth having a higher degree of biaxial crystal orientation without forming an irregular part a3. The method for producing a substrate for epitaxial growth comprising a step of laminating a metal base material and a copper layer having an fcc rolling texture by surface-activated bonding, a step of applying mechanical polishing to the copper layer, and a step of carrying out orientation heat treatment of the copper layer, wherein the copper layer is laminated in such a way that, when ratios of the (200) plane of the copper layer before laminated and of the copper layer after laminated when measured by XRD are I0.sub.Cu and I0.sub.CLAD, respectively and ratios of the (220) plane of the copper layer before laminated and of the copper layer after laminated are I2.sub.Cu and I2.sub.CLAD, respectively, I0.sub.Cu<20%, I2.sub.Cu=70 to 90%, and I0.sub.CLAD<20%, I2.sub.CLAD=70 to 90% and I0.sub.CLAD−I0.sub.Cu<13%.

A superconducting fault current limiter (10) is shown. It comprises a cryostatic cooling system (20) for containing a cooling medium (26), a superconducting wire (30) immersed in the cooling medium (26) and configured to carry a current, the superconducting wire (30) becoming non-superconducting above a critical current density, and a plurality of heat dissipation elements spaced along and projecting from the superconducting wire (30), wherein the heat dissipation elements have an electrically insulating coating, and whereby the heat dissipation elements transfer heat from the superconducting wire (30) into the cooling medium (26).

A persistent current switch includes a superconducting wire, a heater, and an insulating member. The superconducting wire includes a substrate and a superconducting layer provided on the substrate. The superconducting layer includes a first principal surface facing the substrate and a second principal surface on an opposite side of the first principal surface. The heater is disposed only on the second principal surface side with respect to the superconducting layer. The insulating member is provided between the second principal surface of the superconducting layer and the heater.

A superconducting coil module includes: a superconducting coil configured by winding a superconducting wire a plurality of times; and a magnetic dam wound along a shape of the superconducting coil, and electromagnetically coupled. The magnetic dam may include a conductive structure device insulated from the superconducting coil, and implemented by a conductive wire wound along the shape of the superconducting coil a plurality of times, and a control circuit controlling current which flows to the magnetic dam during charging and discharging of the superconducting coil between both terminals of the conductive wire.

A quench protection system for a superconducting machine, such as a superconducting generator having a plurality of series-arranged superconducting coils, includes at least one switch heater electrically coupled to each of the superconducting coils. A quench protection switch is provided in series with the coils, wherein each switch heater is in thermal contact with the quench protection switch. A heater network is configured in parallel with the quench protection switch and is in thermal contact with each of the coils. A quench of any one of the coils triggers a quench of the quench protection switch, wherein the heater network then triggers a quench of all of the remaining coils.

Provided is a superconducting coil having a spiral structure for a current limiter. The coil includes: a first superconducting tape, a second superconducting tape, and an insulating isolation layer, where the first superconducting tape and the second superconducting tape have spiral structures, an end of the first superconducting tape at a spiral center is connected to an end of the second superconducting tape at the spiral center, the instating isolation laser is filled between the first superconducting tape and the second superconducting tape, and a spacing between the first superconducting tape and the second superconducting tape gradually increases from the spiral center to an outer spiral periphery.

A superconducting device includes a superconducting cable having a plurality of superconducting tapes in a plurality of phases, including a first phase, and at least one further phase. One or more superconducting tapes of the first phase is in electrical contact with one or more superconducting tapes of the at least one further phase through at least one resistive barrier that prevents current from passing between the first phase and the at least one further phase in the absence of a voltage between one or more of the superconducting tapes of the first phase or the at least one further phase. The first phase is electrically connected in series to at least one further phase.

A radial-gap type superconducting synchronous machine 1 is prepared which includes a rotor 20 having, on its peripheral side, a convex magnetic pole 21 which includes, at its distal end part, bulk superconductors 30. When viewed in the direction of the rotational axis C1 of the rotor 20, the magnetic pole center side of the bulk superconductors 30 is disposed nearer to a stator 10 than the magnetic pole end side of the bulk superconductors 30. A ferromagnet 28 is disposed on the rotational axis C1 side of the bulk superconductors 30. A magnetizing apparatus 100 is disposed outside the bulk superconductors 30 in the radial direction of the rotor 20. Magnetization of the bulk superconductors 30 is performed by directing magnetic flux lines from the magnetizing apparatus 100 toward the bulk superconductors 30.