Design and production of high-Tc superconducting power transmission cable

The design and production of high temperature superconducting (HTS) power transmission cables was studied. In the production of HTS cable, difficulties are mainly caused by the poor mechanical properties of HTS tapes, because critical currents of the HTS tapes deteriorate due to the strains applied during cable production and usage. Therefore, two basic characteristics of HTS cables were experimentally analyzed to improve HTS cable design and production: (1) the mechanical-electrical properties of the HTS cable; and (2) the properties of electrical insulation. The analysis results indicate that the most important technology is the control of the strains applied to the tape in the cable. Based on the results, the design of the HTS cable was then improved, and the machines at Furukawa Electric fabricated a three-phase prototype HTS cable of 30 m in length. The results of the performance test of the cable demonstrated the proposed design and the production method are appropriate.