Comparison of numerical methods for modeling of superconductors

Abstract

Different finite-element method (FEM) formulations have been developed in order to model the electromagnetic behavior of type-II superconductors. This paper presents a comparison between simulations with A-formulation models implemented in two FEM software packages (FLUX2D and FLUX3D) and a numerical method based on analytical model for superconductors in applied magnetic field. These models can be used for superconductors with complex geometry and power-law current-voltage characteristics. Simulated is a 37-filamentary tape with applied transport current in self-field and alternating current (ac) magnetic field parallel to the wide side of the tape. A good agreement is found between the ac-loss and current distributions obtained with the different models.

Dynamic Field Mapping for Obtaining the Current Distribution in High-Temperature Superconducting Tapes

“…One of the advantages of the finite element method (FEM) is the fact that it gives the possibility to calculate precisely the current and field distribution inside superconducting wires with complex geometries [8], [9]. However, it is not possible to measure directly the current distribution inside the samples and to verify the FEM results even for superconductors with simple geometries.…”

3-D Finite Element Simulations of Strip Lines in a YBCO/Au Fault Current Limiter

“…The value of ρ 0 is chosen according to the criterion given in [5]. Its value has to be less than 10 −2 E c /J c .…”

“…The group at the Swiss Federal Institute of Technology has demonstrated the feasibility of using this software for 2D and 3D simulations of HTS in different applications (transport current and applied external magnetic field). More detailed description of the numerical implementation in Flux 3D, including some other examples, can be found in [5] [6].…”

Analysis of Magnetic Field and Geometry Effects for the Design of HTS Devices for AC Power Applications

“…The 2D FEM model of HTS used the magnetic vector potential A and the electric potential V as state variables. Details can be found in [6]. The HTS is described by means of a non-linear power-law relation E = E c (J/J c (B)) n(B) .…”

“…In particular, the influence of the winding gap between the tapes and the use of a bifilar winding have been studied. For this aim, we have utilized finite-element method (FEM) simulations, which allow precise computation of the current and field distribution, including the AC losses in the superconductor, and taking into account the local effects of the magnetic self-field [5], [6].…”