Compact GdBa₂Cu₃O7–δcoated conductor cables for electric power transmission and magnet applications

Bundling high-temperature superconductors together to form high-current cables is required in, for instance, power transmission and low-inductance magnet applications. Cabling techniques that have been applied so far have not resulted in compact, mechanically robust, high-current cables that remain flexible. Here, we demonstrate that the cabling technique that we have introduced only recently enables the construction of cables from high-temperature superconducting coated conductors that meet these requirements. We present details of a cable, wound from GdBa 2 Cu 3 O 7–δ coated conductors, that has an outer diameter of 7.5 mm and a critical current of about 2800 A at 76 K and self-field. The compact size and flexibility make the cable suitable for Navy and Air Force power transmission, and would allow superconducting power transmission lines that have been installed in the electric power grid to be reduced in diameter. The potential of increasing the engineering current density of the cable, while maintaining flexibility, makes them also suitable for high-field magnet applications.