Superconducting interconnects with ultra-low thermal conductivity capable of providing a direct connection between a millikelvin temperature environment and a 70 K temperature environment.

Superconducting interconnects with ultra-low thermal conductivity capable of providing a direct connection between a millikelvin temperature environment and a 70 K temperature environment.

A superconductive conductor and method of using the superconductive conductor is described. The superconductive conductor includes a plurality of first conductive strips with a first width and a plurality of second conductive strips with a second width, and a strip stack formed from the first and second conductive strips that has a cruciform-shaped cross section.

A superconductive conductor and method of using the superconductive conductor is described. The superconductive conductor includes a plurality of first conductive strips with a first width and a plurality of second conductive strips with a second width, and a strip stack formed from the first and second conductive strips that has a cruciform-shaped cross section.

There is set forth herein a superconducting lead assembly comprising: a positive superconducting wire; a negative superconducting wire, wherein the positive superconducting wire is configured to conduct inflow current to a cryogenic apparatus and wherein the negative superconducting wire is configured to conduct outflow current away from the cryogenic apparatus; and an electrically insulating separator, wherein the positive superconducting wire and the negative superconducting wire are arranged proximately one another and on opposite sides of the electrically insulating separator for cancellation of electromagnetic forces attributable to current flowing simultaneously in opposite directions within the positive superconducting wire and the negative superconducting wire, and wherein a length of the superconducting lead assembly is flexible. In one embodiment the positive superconducting wire and the negative superconducting wire can include high temperature superconducting (HTS) material.

There is set forth herein a superconducting lead assembly comprising: a positive superconducting wire; a negative superconducting wire, wherein the positive superconducting wire is configured to conduct inflow current to a cryogenic apparatus and wherein the negative superconducting wire is configured to conduct outflow current away from the cryogenic apparatus; and an electrically insulating separator, wherein the positive superconducting wire and the negative superconducting wire are arranged proximately one another and on opposite sides of the electrically insulating separator for cancellation of electromagnetic forces attributable to current flowing simultaneously in opposite directions within the positive superconducting wire and the negative superconducting wire, and wherein a length of the superconducting lead assembly is flexible. In one embodiment the positive superconducting wire and the negative superconducting wire can include high temperature superconducting (HTS) material.

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.

A superconducting electrical power distribution system has a superconducting bus bar and one or more bus bar thermal conductor lines extending in thermal proximity along the bus bar to receive heat from the bus bar over the length of the bus bar. The system further has superconducting cables electrically connected to the bus bar at respective electrical joints distributed along the bus bar. The system further has a cryogenic cooling sub-system. The system further has a network comprising first and second thermal conductor lines, each line comprising a cold end which is cooled by the cryogenic cooling sub-system, and an opposite hot end, whereby heat received by each line is normally conducted along the line in a direction from its hot end to its cold end.

A thermal-insulated multi-walled pipe for superconducting power transmission comprises: a superconducting cable; a multi-walled pipe composed of a plurality of straight pipes and houses the superconducting cable; and a plurality of spacers that are located between adjacent two straight pipes of the plurality of straight pipes, wherein a cross-sectional shape of each spacer is a polygon having three or more vertices, each spacer has a through-hole at a center in the plane, an inner straight pipe is located to pass through the through-hole, a frictional coefficient .sub.i between each spacer and the inner straight pipe is 0.1 or less, a frictional coefficient .sub.o between each spacer and an outer straight pipe is 0.1 or less, and a ratio L.sub.d/d of a diagonal equivalent length L.sub.d of the polygon to an inner diameter d of the outer straight pipe of the adjacent two straight pipes is 0.9 or less.

Provided is a thermal-insulated multi-walled pipe for superconducting power transmission that highly prevents intrusion of external heat due to radiation and has excellent thermal insulation property without using a superinsulation and can be produced easily. A thermal-insulated multi-walled pipe for superconducting power transmission comprises: a superconducting cable; and a multi-walled pipe that houses the superconducting cable, wherein the multi-walled pipe is composed of a plurality of straight pipes, and at least one of the plurality of straight pipes has, at a surface thereof, a coating layer containing a metal powder.