Impact of the Magneto Angular Dependence of the Critical Current Density in CORC Cables

With the advent of CORC cables as one of themost suitable conductor technologies for the development of ultra high magnetic field applications, the understanding of their physical properties at a local level and how these influence the macroscopically averaged quantities such as the AC losses, is of the utmost importance as their ulterior optimization and further engineering development depends on it. In this sense, within the electromagnetic scenario, in this paper we present a thorough discussion on how the distribution of critical current and critical current density inside the multiple tapes of a CORC cable can be predicted by three-dimensional finite element methods, and how these diverge when most simple scenarios such as a constantJcequivalent to the self-field critical current condition for straight tapes, or aJc(B)function like the Kim’s model, are both contrasted with the most realisticJc(B,θ)function which encompasses the magneto angular dependence of the HTS tapes. Clearly distinctive features have been found between these three approaches, revealing an anisotropic distribution of the critical current density along the helix tapes when the magneto angular dependence is considered, but with equivalent distribution of magnetization currents, and therefore responding equally in terms of the calculated hysteretic losses when the CORC cable is subjected to an applied magnetic field in perpendicular direction to the cable’s former.