Abstract

The development of the high-temperature superconductors (HTS) has allowed the emergence of diverse superconductor devices. Some of these devices, like wind power generators and high-field magnets, are classified as large-scale HTS systems, because they are made of several hundreds or thousands of turns of conductors. The electromagnetic analysis of such systems cannot be addressed by means of the available analytical models. The finite-element method has been extensively used to solve the H formulation of the Maxwell’s equations, thus far with great success. Nevertheless, its application to large scale HTS systems is still hindered by excessive computational load. The recently proposed T-A formulation has allowed building more efficient models for systems made of HTS tapes. Both formulations have been successfully applied in conjunction with the homogenization and multi-scaling methods, these advanced methods allow reducing the required computational resources. A new advanced method, called densification, is proposed here. The most important contribution of this article is the comprehensive comparison of the strategies emerged from the combined use of the two formulations and the three advanced methods.

Highlights

  • The current density in both analyzed and non-analyzed tapes is multiplied by the thickness of the superconducting layer δ to obtain a surface current density K to be imposed into the A formulation, see equations (8) and (9). As it was the case with the H simultaneous multi-scale models, the degrees of freedom (DOF) can be reduced by means of the homogenization or densification of the non-analyzed tapes

  • The models using an advanced method represent a good alternative to the full models, an alternative that is more significant in the cases where the size of the system complicates or makes the implementation of full models impossible

  • The T-A formulation has proven to be more efficient to model systems made of high-temperature superconductors (HTS) tapes

Read more

Summary

Introduction

More than three decades after the discovery of the first high temperature superconductor (HTS) with a critical temperature. The multi-scaling method is based on the analysis of a reduced set of tapes, called analyzed tapes, and the subsequent approximation of the behavior of the full system [13] As of today, these two advanced methods have been successfully used together with the H and T-A formulation, giving rise to the following strategies: H homogeneous [15], H multi-scale [13], H iterative multi-scale [49], T-A homogeneous [50], and T-A simultaneous multi-scale [50]. The strategies coupling the H formulation and the advanced methods are described, the strategies and their respective models are presented first, and the simulation results are presented together at the end of this section to facilitate their comparison. The strategies coupling the H and T-A formulations and the advanced methods are described in sections 4 and 5, respectively The strategies and their respective models are presented first, and the simulation results are presented together at the end of each section to facilitate their.

Formulations
H formulation
T-A formulation
Case study
Reference model
H and T-A full models
Results
Homogenization
Densification
Multi-scaling
Iterative multi-scaling
Simultaneous multi-scaling
Comparison
User friendliness
Conclusions
Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call