DEVELOPMENT OF A HIGH-CURRENT HTS PROTOTYPE CONDUCTOR FOR POWER TRANSMISSION

Extensive investigation, carried out worldwide until 1980, about the p ossible use of ''conventional'', low-T-c superconductors, in power tra nsmission technology, had led to the unanimous conclusion that liquid- helium-cooled cables, though technically attractive, were not economic ally competitive with conventional systems unless extremely high, unre alistic, power levels had to be transmitted. The availability of HTS m aterials, potentially suitable for cooling with liquid nitrogen, has g iven an extraordinary impulse to revitalize widespread interest for su ch an application. Today, demonstration programs for HTS cable systems and system prototypes have entered the phase of experimental activity , with very positive results. Among the most recent advances is the su ccessful manufacture of a machine-stranded, 50 m long, 3300 ampere HTS cable conductor, which was developed in the frame of an EPRI funded p roject focused on the potential application of HTS cables to retrofit and upgrade existing high-pressure, fluid-filled (HPFF) ''pipe-type'' cable circuits. The next, on-going, phase will be to complete the manu facturing of the cable and of the other components of the system. It i s expected that these initial programs will be followed by pilot insta llations, which will provide the opportunity for establishment of rele vant operational procedures.