Comparison of first‐ and second‐order 2D finite element models for calculating AC loss in high temperature superconductor coated conductors

Purpose – The purpose of the paper is to provide a comparison of first‐ and second‐order two dimensional finite element models for evaluating the electromagnetic properties and calculating AC loss in high‐temperature superconductor (HTS) coated conductors.Design/methodology/approach – The models are based on the two‐dimensional (2D) H formulation, which is based on directly solving the magnetic field components in 2D. Two models – one with a minimum symmetric triangular mesh and one with a single‐layer square mesh – are compared based on different types of mesh elements: first‐order (Lagrange – linear) and second‐order (Lagrange – quadratic) mesh elements, and edge elements.Findings – The number and type of mesh elements are critically important to obtain the minimum level of discretization to achieve accurate results. Artificially increasing the superconductor layer and choosing a minimum symmetric mesh with triangular edge elements can provide a sufficiently accurate estimation of the hysteretic superco...

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