3D FEM Modelling of CORC Commercial Cables with Bean's like magnetization currents and its AC-Losses Behaviour

TL;DR

This paper develops a comprehensive 3D finite element model to analyze AC losses and current distribution in CORC superconducting cables, aligning well with experimental data and advancing understanding of their electromagnetic behavior.

Contribution

It introduces a detailed 3D FEM model based on the H-formulation that accurately captures current density and AC losses in CORC cables without non-physical artifacts.

Findings

The model accurately predicts AC losses beyond 60 mT magnetic field.

Current density distribution along and across tapes is characterized.

Good agreement with experimental measurements is achieved.

Abstract

The Conductor on Rounded Core (CORC) cables manufactured by Advanced Conductor Technologies with current densities beyond 300 Amm^-2 at 4.2 K, and bending diameter of up to 3.5 cm, are considered as one of the strongest candidates for the next generation of high field power applications and magnets. In this paper, we present a full 3D FEM model for their monolayer and bilayer CORC cables made with up to three and six superconducting tapes respectively, disclosing the full curve of AC losses for the monolayer cable at magnetic fields beyond 60 mT, and the actual distribution of current density along and across the thickness of the superconducting tapes in both designs. The model is based on the so-called H-formulation, allowing to incorporate the true three-dimensionality of the tapes without recurring to 2D thin-film approaches where non-physical surface currents that do not follow the celebrated Bean's model for type-II superconductors appear. Likewise, good agreement with the experimentally measured AC-losses for the monolayer and bilayer cable have been obtained, with all the details of the model disclosed in this paper.