# US 7,743,485 B1 · Method of manufacturing a superconducting cable > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 7,743,485 B1 - Document ID: US7743485B1 - Status: Granted - Kind: B1 - Application number: 11/525,262 - Filed: 2006-09-22 - Granted: 2010-06-29 - Earliest claimed: 2003-06-19 - Assignees: Sumitomo Electric Industries, Ltd. - Inventors: Jun Fujikami - Web page: https://patentgrep.com/patent/US7743485B1 ## CPC - H01B 12/02: characterised by their form - H01R 4/68: Connections to or between superconductive connectors - H02G 15/34: Cable fittings for cryogenic cables {(superconductive cables per se H01B12/00)} - Y02E 40/60: Superconducting electric elements or equipment; Power systems integrating superconducting elements or equipment - Y10T 29/49014: Superconductor - H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K}) - H01R: ELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS - H02G: INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract Provided is a superconducting cable having a structure such that cable cores, each having a superconducting layer, are housed in a thermal insulation pipe and the superconducting layer of each cable core has portions having different critical current values. When an excessive current flows in the superconducting layer in case of a short-circuit failure, the current exceeds the critical current value of the portion having a smaller critical current value first, which results in damage to the portion, suppressing the occurrence of damage to the other normal portion. A superconducting cable line using this superconducting cable and a splitter for accommodating the cable cores therein is also provided. ## Claims ### Claim 1 A method of manufacturing a superconducting cable comprising: employing a superconducting layer in at least one cable core, the superconducting layer in the at least one cable core having a first, current limiting superconducting cable portion and a second, normal superconducting cable portion, the first portion having a critical current value different from a critical current value of the second portion, each of the first portion and the second portion having a plurality of clad wires comprising a superconductive material; wherein making the superconducting layer comprises making the critical current value of the first portion to be smaller than that of the second portion and assembling the first portion and the second, normal portion; and housing the first portion inside a splitter configured to separate cable cores; wherein the clad wires of the first portion are fewer in number than the clad wires of the second portion so that the amount of the superconductive material in the first portion is reduced compared to the second portion, and wherein assembling the first portion and the second portion comprises coupling the clad wires of the first portion with the clad wires of the second portion. ### Claim 2 (depends on 1) The method of manufacturing a superconducting cable, as recited in claim 1, wherein the critical current value of the first portion is about 90% of the critical current of the second portion. ### Claim 3 (depends on 1) A method of manufacturing a superconducting cable, as recited in claim 1, further comprising providing a shielding layer at the outer periphery of the superconducting layer. ### Claim 4 (depends on 1) A method of manufacturing a superconducting cable, as recited in claim 1, wherein the at least one cable core comprises a plurality of the cable cores, each including the superconducting layer and having the first portion and the second portion as recited in claim 1. ### Claim 5 (depends on 4) A method of manufacturing a superconducting cable, as recited in claim 4, further comprising cooling the superconducting cable with a coolant filling the splitter, and regulating the pressure in the splitter using a regulating valve when the coolant vaporizes. ### Claim 6 (depends on 4) A method of manufacturing a superconducting cable, as recited in claim 4, wherein housing the first, current limiting superconducting portion inside a splitter comprises placing the first, current limiting superconducting portion in a splitter at a position distanced from the second portion of the cable cores; further comprising placing the first, current limiting superconducting portion at the end portion of the cable cores in the case of the splitter being a termination splitter, and at a central position in the case of the splitter being an intermediate splitter. ### Claim 7 (depends on 1) The method of manufacturing a superconducting cable, as recited in claim 1, wherein coupling the clad wires of the first portion with the clad wires of the second portion comprises soldering the clad wires of the first portion and the clad wires of the second portion. ### Claim 8 (depends on 1) The method of manufacturing a superconducting cable, as recited in claim 1, wherein the first portion is a sacrificial portion for absorbing damage caused by a short-circuit failure and for reducing damage caused by the short-circuit failure to the second portion. ### Claim 9 (depends on 1) The method of manufacturing a superconducting cable, as recited in claim 1, further comprising laying the at least one cable core in duct lines under ground. ### Claim 10 (depends on 1) The method of manufacturing a superconducting cable, as recited in claim 1, wherein the at least one cable core comprises a plurality of cable cores and the splitter is configured to separate the cable cores from each other along their respective length dimensions by arranging the cable cores with their length dimension at an angle so that a distance between the cable cores increases in one direction along the length dimension. ### Claim 11 (depends on 10) The method of manufacturing a superconducting cable, as recited in claim 10, further comprising: containing a coolant in the splitter, for cooling the superconducting cable; and regulating a pressure inside the splitter when the coolant vaporizes in the splitter. ### Claim 12 (depends on 11) The method of manufacturing a superconducting cable, as recited in claim 11, wherein the coolant vaporizes when the current limiting portion is quenched in response to a current. ### Claim 13 (depends on 1) The method of manufacturing a superconducting cable, as recited in claim 1, wherein the at least one cable core comprises a plurality of cable cores and wherein the method further comprises housing the first, current limiting portion of each of the plurality of cable cores in a splitter housing structure and separating the plurality of cable cores from each other.