Mechanical behavior of HTS tapes in highly flexible REBCO cable under torsional and tensile loads

Abstract Different cables composed of high-temperature superconducting (HTS) tapes (REBCO) have been developed for the generation of high magnetic fields and the transmission of large currents. Among the different HTS cables, the conductor on round core (CORC ® ) cable has become a promising candidate structure. In order to improve the flexibility of CORC ® cable, a new kind of cable called HFRC (highly flexible REBCO cable) has been proposed, which has a similar configuration to CORC ® cable. During the production of HFRC, REBCO tapes are wound on the surface of a spiral tube layer by layer. Compared to the solid core of traditional CORC ® cable, the spiral tube is more prone to complex deformation under external loads, which results in special characteristics of REBCO tapes. In this paper, we analyze the deformation processes of spiral tubes under tension or torsion. Based on the geometrical relationship between the tapes and the cable core, the strain in REBCO tapes is predicted. Finite element models of HFRC/traditional CORC-like cable are built and verified by experiments. Through simulations, the variation of the strain and local creases of the tapes with the design parameters of the core is investigated. Relevant findings provide a reference for the structural optimization of HFRC.