Power transmission systems with cooling mechanisms, and methods of operating the same, are described. A power transmission system can include multiple support tower assemblies. Each of the support tower assemblies includes a support tower. One or more of the support tower assemblies includes a termination (i.e., a connection point via which electrical current and/or coolant can enter the transmission line and/or exit the transmission line). The power transmission system also includes multiple conductor assemblies suspended above a surface of the earth. Each conductor assembly includes an electrical conductor and is positioned between, and mechanically supported by, a pair of the support towers. The power transmission system also includes a coolant supply system that delivers a coolant fluid, during operation of the power transmission system, to at least one of the terminations, for cooling of the conductor assemblies.

The present invention is a superconducting wire including: a wire formed of a superconducting material; and a superconducting stabilization material disposed in contact with the wire, in which the superconducting stabilization material is formed of a copper material which contains: one or more types of additive elements selected from Ca, Sr, Ba, and rare earth elements in a total of 3 ppm by mass to 400 ppm by mass; a balance being Cu and inevitable impurities, and in which a total concentration of the inevitable impurities excluding O, H, C, N, and S which are gas components is 5 ppm by mass to 100 ppm by mass.

A coated conductor comprises a substrate supporting a ReBCO superconductor adapted to carry current in a superconducting state. The superconductor is characterized in having peaks in critical current (J.sub.c) of at least 0.2 MA/cm.sup.2 in a magnetic field of about 1 Tesla when the field is applied normal to the surface of the superconductor and when the field is applied parallel to the surface of the superconductor, and further characterized in that the superconductor includes horizontal defects and columnar detects in a size and an amount sufficient to result in the said critical current response. The conductor is characterized in that the ratio of the height of the peaks in the J.sub.c is in the range from 3:1 with the ratio of the field perpendicular (0 degrees) to the field parallel (+/−90 degrees) to the range from 3:1 with the ratio of the field parallel to the field perpendicular.

A coated conductor comprises a substrate supporting a ReBCO superconductor adapted to carry current in a superconducting state. The superconductor is characterized in having peaks in critical current (J.sub.c) of at least 0.2 MA/cm.sup.2 in a magnetic field of about 1 Tesla when the field is applied normal to the surface of the superconductor and when the field is applied parallel to the surface of the superconductor, and further characterized in that the superconductor includes horizontal defects and columnar detects in a size and an amount sufficient to result in the said critical current response. The conductor is characterized in that the ratio of the height of the peaks in the J.sub.c is in the range from 3:1 with the ratio of the field perpendicular (0 degrees) to the field parallel (+/−90 degrees) to the range from 3:1 with the ratio of the field parallel to the field perpendicular.

According to an embodiment, a superconductor includes a base member, and a superconducting layer provided on the base member. The superconducting Layer has a first surface on the base member side, and a second surface on the side opposite to the first surface. The lattice constant of the base member substantially matches the lattice constant of the superconducting layer. The superconducting layer includes REA.sub.1-xREB.sub.xBa.sub.2Cu.sub.3O.sub.7-z. The x is not less than 0.01 and not more than 0.40. The z is not less than 0.02 and not more than 0.20. The REA includes at least one of Y, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu. The REB includes at least one of Nd or Sm. The superconducting layer includes a first surface-side region including a portion of the first surface. The first surface-side region includes a first region having an orientation property, and a second region.

A superconducting coil comprising an oxide superconducting wire includes: a superconducting laminate comprising a substrate and an oxide superconducting layer; and a stabilization layer made of copper plating formed around the superconducting laminate. A thickness d of the stabilization layer is in the range of 10 to 40 μm. A ratio Ra/d of the thickness d of the stabilization layer and an arithmetic mean roughness Ra of an outer surface of the stabilization layer is in the range of 0.005 to 0.03. An intermediate layer is arranged between the substrate and the oxide superconducting layer. When a tensile test of pulling the oxide superconducting wire in a longitudinal direction within a stress range of 180 to 600 MPa in liquid nitrogen is performed, a ratio of a critical current when a repeated pulling number reaches 100,000 times and an initial critical current measured before the tensile test is 0.99 or more.

A superconducting coil comprising an oxide superconducting wire includes: a superconducting laminate comprising a substrate and an oxide superconducting layer; and a stabilization layer made of copper plating formed around the superconducting laminate. A thickness d of the stabilization layer is in the range of 10 to 40 μm. A ratio Ra/d of the thickness d of the stabilization layer and an arithmetic mean roughness Ra of an outer surface of the stabilization layer is in the range of 0.005 to 0.03. An intermediate layer is arranged between the substrate and the oxide superconducting layer. When a tensile test of pulling the oxide superconducting wire in a longitudinal direction within a stress range of 180 to 600 MPa in liquid nitrogen is performed, a ratio of a critical current when a repeated pulling number reaches 100,000 times and an initial critical current measured before the tensile test is 0.99 or more.

Coils for superconducting magnets and methods of making coils for superconducting magnets and controlling the turn-to-turn contact resistance of coils. The coils include a REBCO superconducting tape coated with a layer of tin-lead solder, co-wound with an oxidized stainless steel tape. The inclusion of tin-lead solder on the REBCO tape and a layer of oxidation on the stainless steel tape advantageously allow for tuning of the turn-to-turn contact resistance of the coil, and advantageously mitigates the effect of repeated pressure cycling on the turn-to-turn contact resistance.

A superconducting wire according to one embodiment of the present disclosure includes: a substrate having a first surface and a second surface; a superconducting layer having a third surface and a fourth surface; and respective coating layers. The second surface is opposite to the first surface. The fourth surface is opposite to the third surface. The superconducting layer is disposed on the substrate such that the third surface faces the second surface. The respective coating layers are disposed on the first surface and the fourth surface. Adhesion strength between the substrate and the coating layer disposed on the first surface is lower than adhesion strength between the superconducting layer and the coating layer disposed on the fourth surface.

A superconducting wire according to one embodiment of the present disclosure includes: a substrate having a first surface and a second surface; a superconducting layer having a third surface and a fourth surface; and respective coating layers. The second surface is opposite to the first surface. The fourth surface is opposite to the third surface. The superconducting layer is disposed on the substrate such that the third surface faces the second surface. The respective coating layers are disposed on the first surface and the fourth surface. Adhesion strength between the substrate and the coating layer disposed on the first surface is lower than adhesion strength between the superconducting layer and the coating layer disposed on the fourth surface.