Study of the magnetization loss of CORC cables using a 3D T-A formulation

Conductor on round core (CORC) cable wound with high temperature superconductors (HTS) is an important cable concept for high current density applications. The design of CORC cable makes the understanding of its electromagnetic performance – for example its AC losses – challenging. This paper presents a thorough study for CORC cables by combining experimental and numerical methods. In particular, the paper focuses on understanding how the cable structure influences the magnetization losses and on how these can be reduced. A novelty of this paper lies in the use of a new T-A formulation, which, for the first time, is employed for 3D modelling of CORC cable with real geometry. The use of the new T-A formulation in finite element software enables the study of how the winding direction and multiple-layer structure affect the magnetization losses of CORC cables. Moreover, influence of striation in CORC cable is studied as an effective way to reduce its losses. The CORC cable with striated tapes shows a significant magnetization loss reduction at high magnetic fields, in comparison to its un-striated counterpart. At low magnetic fields, tape striation leads to a loss rise when the number of filaments is low, then the loss drops with the further increase of filaments, but this loss reduction is much weaker than that at high fields. The paper provides an efficient tool for investigating the electromagnetic behaviour of CORC cables, which can provide valuable guidance in designing CORC cables with minimized losses for high energy physics and energy conversion applications