3D computation of non-linear eddy currents: variational method and superconducting cubic bulk

TL;DR

This paper introduces a novel variational method for efficiently computing 3D non-linear eddy currents in superconductors, enabling accurate modeling of complex magnetization phenomena with reduced computational time.

Contribution

A new variational modeling approach with sector-based minimization for fast, accurate 3D eddy current simulations in superconductors and non-linear materials.

Findings

Current flux lines bend significantly below the penetration field.

The method achieves high accuracy with reduced computation time.

It enables detailed analysis of 3D magnetization currents in bulk superconductors.

Abstract

Computing the electric eddy currents in non-linear materials, such as superconductors, is \E{not straightforward}. The design of superconducting magnets and power applications needs electromagnetic computer modeling, being in many cases a three-dimensional (3D) problem. Since 3D problems require high computing times, novel time-efficient modeling tools are highly desirable. This article presents a novel computing modeling method based on a variational principle. The self-programmed implementation uses an original minimization method, which divides the sample into sectors. This speeds-up the computations with no loss of accuracy, while enabling efficient parallelization. This method could also be applied to model transients in linear materials or networks of non-linear electrical elements. As example, we analyze the magnetization currents of a cubic superconductor. This 3D situation remains unknown, in spite of the fact that it is often met in material characterization and bulk applications. We found that below the penetration field and in part of the sample, current flux lines are not rectangular and significantly bend in the direction parallel to the applied field. In conclusion, the presented numerical method is able to time-efficiently solve fully 3D situations without loss of accuracy.