Terminal structure of superconducting cable

摘要

A terminal structure of a superconducting cable is provided that is capable of preventing degradation in airtightness of a seal provided on the boundary between a room-temperature side and a cryogenic side for a long-term use. The terminal structure includes a terminal of a superconducting cable, a bushing providing electrical conduction with a superconducting conductor of the cable, and a refrigerant bath housing the terminal and the bushing. The refrigerant bath includes a liquid nitrogen layer in its cryogenic side and a nitrogen gas layer in its room-temperature side that are adjacent to each other. In the nitrogen gas layer, distance t between an inner surface of the refrigerant bath and an outer periphery of the bushing is dimensioned such that nitrogen gas is kept in a gaseous state without being pressurized by a pressurizer and respective pressures of nitrogen gas and liquid nitrogen counterbalance each other.