Additional Opportunities of AC Losses Minimization in HTS Cables Caused By the Enhancement of HTS Tapes Critical Characteristics

Abstract

Recently,the quality of 2G HTS tapes has been significantly improved. E.g., the critical currents of tapes produced by S-innovations LLC nowadays are actually twice as much as ones of previous samples, and the improvement of the uniformity of characteristics over the length allowed a stable operation of tapes with the thickness of copper coating of 5–10 µm, instead of 40–60 µm used before. This allows not only the development of HTS cables with higher rated currents but also reduction of AC losses in ordinary cables with critical currents no more than 5 kA. In particular, increasing of the critical current allows reduction of the HTS tape layers number in cable phases without changing of its overall dimensions. And the decreasing of the copper coating thickness enables the reduction of the distance between HTS coatings in adjacent layers of HTS tapes without changing their ordinary configuration. In this paper is given the qualitative analysis of the efficiency of these two methods to reduce AC losses. The calculations were performed for triaxial cables and ones with screened phases with the use of the numerical simulation technique.