Low resistance cabled conductors comprising superconducting ceramics

A method of using a cabled conductor having a rated temperature and a rated current in a cryogenically cooled circuit including a refrigeration means having a predetermined efficiency and a predetermined operating temperature no less than the rated temperature of the cabled conductor, the conductor having a longtudinal axis and including

• a plurality of conductor strands bent around the longitudinal axis of the conductor at a preselected cabling period, each strand including a composite of one or more superconducting ceramic filaments and a conductive matrix material,
• the bends in each conductor strand causing periodic poorly superconducting regions in each filament therein, each of the poorly superconducting regions in each filament having a length that is at lest about half the width of that filament,
• the conductive matrix material being in intimate contact with the poorly superconducting regions to provide an alternate current path,
• the method comprising the steps of:
• cooling the conductor to the operating temperature of the refrigeration means;
• and
• supply a current along the longitudinal axis of the conductor which is less than the rated current of the conductor but greater than the critical current of at least one of the poorly superconducting regions.

A method of using a cabled conductor having a rated temperature and a rated current in a cryogenically cooled circuit including a refrigeration means having a predetermined efficiency and a predetermined operating temperature no less than the rated temperature of the cabled conductor, the conductor having a longitudinal axis and including

• a plurality of conductor strands bent around the longitudinal axis of the conductor at a preselected cabling period, each strand including a composite of one or more superconducting ceramic filaments and a conductive matrix material,
• the bends in each conductor strand causing periodic poorly superconducting regions in each filament therein, each of the poorly superconducting regions in each filament having a length that is at least about half the width of that filament,
• the conductive matrix material being in intimate contact with the poorly superconducting regions to provide an alternate current path,
• the method comprising the steps of:
• cooling the conductor to the operating temperature of the refrigeration means;
• and
• applying a predetermined magnetic field to the conductor having a primary component orthogonal to the preferred direction of the conductor which is less than the rated magnetic field of the conductor but greater than the critical magnetic field of at least one of the poorly superconducting regions.