Critical current of a quasi-isotropic HTS strand with symmetric configuration

Abstract

This paper presents a quasi-isotropic (QI) high temperature superconducting (HTS) strand which was designed by geometrically and symmetrically arranged by four stacks each of which consisted of 18 ReBCO coated conductors (ReBCO CC), its outer sheaths may be copper, aluminum and stainless steel (SS) which functions as stabilizers and jackets. A dummy model of the strand with square cross-sections was fabricated in order to assess the feasibility of reducing the anisotropic critical current and improving current carrying capacity. Its critical current at self field was calculated at different transport currents. Due to its geometrically symmetric configuration, the goal is to improve its anisotropic critical current resulting from the critical current in ReBCO CC is anisotropic. The anisotropic critical current was experimentally tested in self field and relative low external direct current (DC) magnetic field and 77 K, the results indicate that the anisotropy of its critical current is improved too much in low magnetic fields, and at least the strand can be quasi-isotropic.