Abstract: Provided is a superconducting cable configured to improve superconductivity by increasing reflectivity of cryostats and enhancing cooling performance. The superconducting cable includes: a core provided with a conductor; and a cryostat surrounding a periphery of the core. A material of the cryostat is aluminum or an aluminum alloy and a surface roughness of the cryostat is 30 microns or less in terms of RMS value.

Abstract: Disclosed herein is a shielding conductor connecting structure of a terminal for super-conductor cable. The shielding conductor connecting structure includes an inner cryostat for forming an extremely low temperature portion while having a super-conductor cable formed therein, an outer cryostat formed with an interval so that a shielding conductor is extracted from the super-conductor cable, a plurality of vacuum tubes formed at an interval to protrude along an outer circumferential surface of the outer cryostat, a short-circuit conductor formed in each of the vacuum tubes to be connected to another phase connection portion and a short-circuit conductor connection portion formed in the interior of the outer cryostat and connected to the short-circuit conductor in the vacuum tube while being connected to the shielding conductor connected to the super-conductor cable.

Abstract: Disclosed herein is a temperature movable structure of a superconducting cable terminal. The superconducting cable terminal has sections of a high temperature portion, a temperature movable portion and an extremely low temperature portion. The temperature movable structure is disposed in the section of the temperature movable portion between the sections of the high temperature portion and the extremely low temperature portion. The temperature movable structure has upper and lower spacer members, a pipe body, first and third conductors, a second conductor and a contact connecting member disposed between the first and second conductors.

Abstract: A superconductive cable is provided which upon normal state, restricts flowing of electric current to a former to the maximum extent to thereby keep a cryogenic state in the superconductive cable stable. The superconductive cable includes a former surrounded by a superconductive layer and a cryostat provided at the outside of the superconductive layer, wherein the former includes a metal wire-wound part around which a plurality of wires is wound and an eddy-current prevention layer provided on the outer face of the wire-wound part, and the metal wires and the eddy-current prevention layer are made of a copper alloy.

Abstract: Disclosed is a superconducting power cable capable of quench detection, and a quench detection system using the superconducting power cable. The superconducting power cable capable of quench detection includes a former; a superconducting conductor layer composed of a superconducting wire and surrounding the former; a conductor layer quench detection coil interposed between the former and the superconducting conductor layer and surrounding the former; an insulating layer surrounding the superconducting conductor layer; and a shielding layer surrounding the insulating layer. This superconducting power cable may detect quench generated during its operation in real time.

Abstract: Disclosed is a superconducting power cable capable of quench detection, and a quench detection system using the superconducting power cable. The superconducting power cable capable of quench detection includes a former; a superconducting conductor layer composed of a superconducting wire and surrounding the former; a conductor layer quench detection coil interposed between the former and the superconducting conductor layer and surrounding the former; an insulating layer surrounding the superconducting conductor layer; and a shielding layer surrounding the insulating layer. This superconducting power cable may detect quench generated during its operation in real time.

Abstract: A terminal apparatus for a superconducting cable system connects an overhead transmission cable or power appliance such as a breaker in an ambient temperature state to a superconducting cable through which power is transmitted at a cryogenic temperature. The terminal apparatus has: a refrigerant tub which is connected to the end of a superconducting cable and is filled with a refrigerant; a vacuum heat insulating container that surrounds the exterior of the refrigerant tub; a current lead having one end connected to the end portion of the superconducting cable and the other end connected to the overhead transmission cable or power appliance through the refrigerant tub and the vacuum heat insulating container; and a superconducting fault current limiter installed at a center portion of the current lead in the interior of the refrigerant tub to limit fault current.

Abstract: The present invention relates to a combination twist structure of a superconducting cable core. The present invention relates to a new type of a combination twist structure of a superconducting cable core capable of accommodating the thermal contraction of the cable core in the longitudinal direction without having a space for accommodation, thereby capable of reducing an outer diameter of the superconducting cable, and eliminating the use of an additional equipment for forming the space for accommodation. The present invention provides a combination twist structure of a superconducting cable core formed by twisting a plurality of cable cores. The cable cores are combined by repeatedly changing a twist direction of the cable cores, and the contraction of the cable cores in the longitudinal direction is accommodated by untwisting the cable cores.

Abstract: A cryostat of a superconducting cable disclosed herein includes an inner metallic tube filled with liquid nitrogen and extended along the circumference of a core, an outer metallic tube surrounding the circumference of the inner metallic tube at a distance, a cooling vessel of a terminal connecting box connected to the inner metallic tube and filled with liquid nitrogen, an insulation tube surrounding the circumference of the cooling vessel at a distance, an inner bellows tube connecting an end of the outer metallic tube to the cooling vessel, and an outer bellows tube spaced apart from the inner bellows tube and connecting the end of the outer metallic tube to the insulation tube.

Abstract: An apparatus for supplying liquid nitrogen for a decompression device: includes a liquid nitrogen supply line extending such that high-temperature, high-pressure liquid nitrogen is introduced to a decompression device; a bypass pipe diverging from the liquid nitrogen supply line; and an expansion unit installed at the bypass pipe to evaporate the liquid nitrogen into nitrogen gas. The expansion unit is disposed to absorb heat from the liquid nitrogen in the liquid nitrogen supply line before being introduced to the decompression device.

Abstract: Disclosed is a superconducting power cable capable of quench detection, and a quench detection system using the superconducting power cable. The superconducting power cable capable of quench detection includes a former; a superconducting conductor layer composed of a superconducting wire and surrounding the former; a conductor layer quench detection coil interposed between the former and the superconducting conductor layer and surrounding the former; an insulating layer surrounding the superconducting conductor layer; and a shielding layer surrounding the insulating layer. This superconducting power cable may detect quench generated during its operation in real time.

Abstract: Provided is a superconducting cable provided with an enhanced cooling ability, the superconducting cable including a core including a superconducting wire rod; an inner sheath surrounding the core; an outer sheath surrounding the inner sheath; a plurality of communication pipes that have both ends communicating with the inner and outer sheaths, and are mounted in the longitudinal direction of the inner and outer sheaths; a plurality of valves that are mounted in the communication pipes; and a plurality of auxiliary cooling systems that are mounted on some of the communication pipes. Cooling fluid supplied from the cooling systems is supplied into the inner sheath through the communication pipes, and is then discharged to the outside through the valves.

Abstract: A superconductive cable is provided which upon normal state, restricts flowing of electric current to a former to the maximum extent to thereby keep a cryogenic state in the superconductive cable stable. The superconductive cable includes a former surrounded by a superconductive layer and a cryostat provided at the outside of the superconductive layer, wherein the former includes a metal wire-wound part around which a plurality of wires is wound and an eddy-current prevention layer provided on the outer face of the wire-wound part, and the metal wires and the eddy-current prevention layer are made of a copper alloy.

Abstract: Disclosed is a superconducting power cable capable of quench detection, and a quench detection system using the superconducting power cable. The superconducting power cable capable of quench detection includes a former; a superconducting conductor layer composed of a superconducting wire and surrounding the former; a conductor layer quench detection coil interposed between the former and the superconducting conductor layer and surrounding the former; an insulating layer surrounding the superconducting conductor layer; and a shielding layer surrounding the insulating layer. This superconducting power cable may detect quench generated during its operation in real time.

Abstract: A cryogenic refrigerator has a separating device provided between a lower temperature portion and a heat exchanger to selectively separate the lower temperature portion and the heat exchanger, and thus to selectively block heat transfer between the lower temperature portion and the heat exchanger. According to the cryogenic refrigerator, it can have an ability to perform a maintenance operation of the cryogenic refrigerator at normal temperature by blocking heat transfer from the lower temperature portion to the heat exchanger during maintenance after disassembly.

Abstract: An intermediate jointing structure having excellent mechanical and electrical characteristics and method of preparing the same. The intermediate jointing structure includes a metal pipe and a jointing sleeve. The metal pipe is inserted between a pair of superconducting cables and is fixed to the formers by welding. A plurality of superconductor wires, shorter than the conductive metal tube, are arranged around a conductive metal tube in a longitudinal direction. The arranged superconductor wires are taped with Ag tape so as to form the jointing sleeve. The jointing sleeve is jointed and fixed on an outer surface of the metal pipe.

Abstract: An intermediate jointing structure having excellent mechanical and electrical characteristics and method of preparing the same. The intermediate jointing structure includes a metal pipe and a jointing sleeve. The metal pipe is inserted between a pair of superconducting cables and is fixed to the formers by welding. A plurality of superconductor wires, shorter than the conductive metal tube, are arranged around a conductive metal tube in a longitudinal direction. The arranged superconductor wires are taped with Ag tape so as to form the jointing sleeve. The jointing sleeve is jointed and fixed on an outer surface of the metal pipe.