Test results of full-scale HTS cable models and plans for a 36 kV, 2 kA(rms) utility demonstration

Cable systems using High-Temperature Superconducting (HTS) tapes are nearin g technical feasibility. Several large-scale demonstrations are under way. This article summarizes the advancements and status of a development projec t aimed at demonstrating a 36 kV, 2 kArms AC cable system through installin g a 30 m long full-scale functional model in a power utility substation. Th e HTS cable line is designed to link two medium-voltage transformer station s in an urban environment. The expected benefits of such a system include r educed energy loss, ease of installation, increased power rating in a small cross section, and Insensitivity to the surrounding soil conditions. Resul ts will be presented from tests on several 2 kA-class AC: conductors. Elect rical Losses below 1 W/m at 2 kArms have been obtained in these table condu ctors, The cable system consists of terminations, three HTS cables with con ventional room-temperature dieleetric and stress cones, and a closed-loop c irculating cooling system maintaining the temperature between 74 and 84 K. Critical issues before the commercialization of this technology is the impr ovement of the thermal insulation, the reliability and maintainability of t he cooling system, and the reduction of materials costs.