Comparison of fast computing methods for ZFC High-temperature superconductors bulks

With the development of high-temperature superconducting (HTS) materials, several HTS applications are been proposed and developed. Due to the HTS non-linear and non-homogeneous electromagnetic characteristics, the optimization process of an HTS system is a complex task requiring high computational time and resources. Within this context, this paper focuses on the comparison of HTS models for a fast estimation of the magnetization level of zero-field cooled HTS bulks. Four HTS models are analyzed: Kim's model, Bean's model, a simplified analytical model considering J = Jc and an equivalent permeability model. As a case study, these models are used to simulate the levitation forces of a horizontal axis HTS levitation system. A 3D Finite Element model is used as a base tool for the implementation of each model. Results are compared with the experimental ones. The simplified analytical model (J = Jc) and the equivalent permeability model present accurate enough results with a very low computational time when compared with Kim's and Bean's models. For the 3D simulation of the levitation system, a computational time between 10 and 24 h is required for the Kim's and Bean's models, while only between 10 and 30 s for the simplified analytical and equivalent permeability models. Besides, the simplified analytical model (J = Jc) also provides information about the eddy-current losses inside the HTS bulks. (paper)