Described are cable joints and related structures and techniques for coupling high temperature superconducting (HTS) cables. A cable joint includes a conductive member having a length which defines the length of the joint and having first and second mounting regions shaped to accept first and second HTS cable with an interface layer comprised of a malleable metal disposed between a surfaces of the first and second mounting regions and surfaces of the first and second HTS cables.

When temperature raising is performed, temperature of a superconducting cable is uniformly raised over an entirety of the superconducting cable. The superconducting cable assumes a linear shape when cooled, and deforms into a helical shape when temperature raising is performed. In a former having a twisted wire structure, twisting directions of an outermost layer and a layer next to the outer most layer are set to be the same, enabling stabilization of the helical deformation of the superconducting cable including the former when the temperature raising is performed.

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.

A current lead assembly for minimizing heat load to a conduction cooled superconducting magnet during a ramp operation is provided. The current lead assembly includes a vacuum chamber having a through hole to enable a first end of a current lead contact to remain outside the vacuum chamber and a second end of the current lead contact to penetrate within the vacuum chamber. A vacuum boundary wall is located between the vacuum chamber and the current lead contact. At least one superconducting magnet is arranged inside of the vacuum chamber and includes a magnet lead. A second end of the current lead contact is coupled to the magnet lead via an internal lead. A vacuum cap is removably disposed to sealingly encompass therein the first end of the current lead contact during a first state of operation. The first end of the current lead contact is arranged to contact a power supply during a second state of operation, wherein the contact occurs exterior the vacuum chamber.

A current lead assembly for minimizing heat load to a conduction cooled superconducting magnet during a ramp operation is provided. The current lead assembly includes a vacuum chamber having a through hole to enable a first end of a current lead contact to remain outside the vacuum chamber and a second end of the current lead contact to penetrate within the vacuum chamber. A vacuum boundary wall is located between the vacuum chamber and the current lead contact. At least one superconducting magnet is arranged inside of the vacuum chamber and includes a magnet lead. A second end of the current lead contact is coupled to the magnet lead via an internal lead. A vacuum cap is removably disposed to sealingly encompass therein the first end of the current lead contact during a first state of operation. The first end of the current lead contact is arranged to contact a power supply during a second state of operation, wherein the contact occurs exterior the vacuum chamber.

A connection structure of a superconducting layer of an embodiment incudes a first superconducting member including a first superconducting layer, and extends in a first direction, a second superconducting member including a second superconducting layer facing the first superconducting layer, and extends in the first direction, the second superconducting member having a first region, a second region, and a third region which is separated in the second direction from the second region, and a connection layer that contains a rare earth element (RE), barium (Ba), copper (Cu), and oxygen (O), and connects the first superconducting layer and the second superconducting layer. The first superconducting layer is present in a third direction between the second region and the third region, the third direction being perpendicular to the first direction and perpendicular to the second direction.

A connection structure of a superconducting layer of an embodiment incudes a first superconducting member including a first superconducting layer, and extends in a first direction, a second superconducting member including a second superconducting layer facing the first superconducting layer, and extends in the first direction, the second superconducting member having a first region, a second region, and a third region which is separated in the second direction from the second region, and a connection layer that contains a rare earth element (RE), barium (Ba), copper (Cu), and oxygen (O), and connects the first superconducting layer and the second superconducting layer. The first superconducting layer is present in a third direction between the second region and the third region, the third direction being perpendicular to the first direction and perpendicular to the second direction.

Provided is a connection structure for superconductor wires, in which two superconductor wires include respective oxide superconducting conductor layers each formed on one surface of a base material. The oxide superconducting conductor layers are conjoined with each other while facing each other at a connected end of each of the two superconductor wires. An embedment material for reinforcement is provided from one of the two superconductor wires to the other one of the two superconductor wires in a thickness direction of the two superconductor wires at the connected end of each of the two superconductor wires.

A superconducting electrical power distribution network has a superconducting bus bar and superconducting cables electrically connected to the bus bar at respective joints distributed along the bus bar. The network further has a first coolant system for providing first cryogenic fluid and first circuits for circulating the first cryogenic fluid provided by the first coolant system. The first circuits comprise: a bus bar flow path which extends along and thereby cools the bus bar, cable flow paths which respectively extend along and thereby cool the cables, cooling junctions where the bus bar and cable flow paths meet at the electrical connection joints, inflow lines which send the first cryogenic fluid from the first coolant system to the flow paths, and outflow lines which remove the first cryogenic fluid from the flow paths.

An example method for connectorizing a superconducting cable is described herein. The method can include depositing an oxide layer on a surface of a superconducting cable, electroplating a metal layer on the surface of the superconducting cable, and soldering a connector to the metal layer coated on the surface of the superconducting cable. The oxide layer allows the metal layer to adhere to the surface of the superconducting cable.