Research on insulation design of 22.9-kV high-T/sub c/ Superconducting cable in Korea

The electrical insulation design is important for high-Tc superconducting (HTS) cable because the cable is operated in a medium voltage environment. For the insulation design of HTS cable, it is necessary to investigate the ac, impulse breakdown, and partial discharge inception stress of a liquid nitrogen/polypropylene laminated paper composite insulation system. These results were used to design the electrical insulation of 22.9-kV-class HTS cable in Korea and cable was manufactured. A manufactured mini-model HTS cable was evaluated for ac withstand voltage, impulse withstand voltage, breakdown and dielectric tangent loss (tan/spl delta/). From these tests, the cable has satisfied the standard technical specification of KEPCO in Korea. The breakdown voltage was 110 kV.