2-D Numerical Modeling of a Bulk HTS Magnetization Based on &lt;bold&gt;H&lt;/bold&gt; Formulation Coupled With Electrical Circuit

Kapek, Jakub; Berger, Kévin; Koblischka, Michael Rudolf; Trillaud, F.; Lévêque, Jean

doi:10.1109/tasc.2019.2897331

Cited by 9 publications

(4 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A surface representing the field mapping area is placed at 2.75 mm above the foam. The calculations were performed using classical H formulation coupled with circuit coupling or external field [ 54 ], or alternatively, using the A–H coupled formulation [ 55 ] implemented in the PDE module and the global equation module in COMSOL Multiphysics version 5.2a. The electrical parameters to simulate the YBCO foam sample use the power law

with the parameters

V/cm,

20, and a critical current density

1000 A/mm

, corresponding to the measurements on foam struts of Ref.…”

Section: Results and Discussionmentioning

confidence: 99%

Microstructural Parameters for Modelling of Superconducting Foams

et al. 2022

Self Cite

View full text Add to dashboard Cite

Superconducting YBa2Cu3Oy (YBCO) foams were prepared using commercial open-cell, polyurethane foams as starting material to form ceramic Y2BaCuO5 foams which are then converted into superconducting YBCO by using the infiltration growth process. For modelling the superconducting and mechanical properties of the foam samples, a Kelvin-type cell may be employed as a first approach as reported in the literature for pure polyurethane foams. The results of a first modelling attempt in this direction are presented concerning an estimation of the possible trapped fields (TFs) and are compared to experimental results at 77 K. This simple modelling revealed already useful information concerning the best suited foam structure to realize large TF values, but it also became obvious that for various other parameters like magnetostriction, mechanical strength, percolative current flow and the details of the TF distribution, a refined model of a superconducting foam sample incorporating the real sample structure must be considered. Thus, a proper description of the specific microstructure of the superconducting YBCO foams is required. To obtain a set of reliable data, YBCO foam samples were investigated using optical microscopy, scanning electron microscopy and electron backscatter diffraction (EBSD). A variety of parameters including the size and shape of the cells and windows, the length and shape of the foam struts or ligaments and the respective intersection angles were determined to better describe the real foam structure. The investigation of the foam microstructures revealed not only the differences to the original polymer foams used as base material, but also provided further insights to the infiltration growth process via the large amount of internal surface in a foam sample.

show abstract

with the parameters

V/cm,

20, and a critical current density

1000 A/mm

, corresponding to the measurements on foam struts of Ref.…”

Section: Results and Discussionmentioning

confidence: 99%

Microstructural Parameters for Modelling of Superconducting Foams

et al. 2022

Self Cite

View full text Add to dashboard Cite

show abstract

“…Naturally, the modelling of HTS machines becomes very complicated and time consuming, no matter which type of formulation is chosen. In order to mitigate the simulation com-plexity, most of the researchers have only focused on the superconducting parts in electric machines and choose 2D models to study the cross section of HTS coils, stacks of tapes, and bulks [84][85][86][87][88][89][90][91][92][93][94][95]. However, the electromagnetic environment inside electric machines is quite complex, and is also decided by non-superconducting parts, such as iron cores and iron slotted structures.…”

Section: Modelling Methodsmentioning

confidence: 99%

Alternating Current Loss of Superconductors Applied to Superconducting Electrical Machines

Zhang¹,

Wen²,

Grilli

et al. 2021

Energies

View full text Add to dashboard Cite

Superconductor technology has recently attracted increasing attention in power-generation- and electrical-propulsion-related domains, as it provides a solution to the limited power density seen by the core component, electrical machines. Superconducting machines, characterized by both high power density and high efficiency, can effectively reduce the size and mass compared to conventional machine designs. This opens the way to large-scale purely electrical applications, e.g., all-electrical aircrafts. The alternating current (AC) loss of superconductors caused by time-varying transport currents or magnetic fields (or both) has impaired the efficiency and reliability of superconducting machines, bringing severe challenges to the cryogenic systems, too. Although much research has been conducted in terms of the qualitative and quantitative analysis of AC loss and its reduction methods, AC loss remains a crucial problem for the design of highly efficient superconducting machines, especially for those operating at high speeds for future aviation. Given that a critical review on the research advancement regarding the AC loss of superconductors has not been reported during the last dozen years, especially combined with electrical machines, this paper aims to clarify its research status and provide a useful reference for researchers working on superconducting machines. The adopted superconducting materials, analytical formulae, modelling methods, measurement approaches, as well as reduction techniques for AC loss of low-temperature superconductors (LTSs) and high-temperature superconductors (HTSs) in both low- and high-frequency fields have been systematically analyzed and summarized. Based on the authors’ previous research on the AC loss characteristics of HTS coated conductors (CCs), stacks, and coils at high frequencies, the challenges for the existing AC loss quantification methods have been elucidated, and multiple suggestions with respect to the AC loss reduction in superconducting machines have been put forward. This article systematically reviews the qualitative and quantitative analysis methods of AC loss as well as its reduction techniques in superconductors applied to electrical machines for the first time. It is believed to help deepen the understanding of AC loss and deliver a helpful guideline for the future development of superconducting machines and applied superconductivity.

show abstract

“…A surface representing the field mapping area is placed at 2.75 mm above the foam. The calculations were performed using classical H formulation coupled with circuit coupling or external field [54], or alternatively, using the A-H coupled formulation [55] implemented in the PDE module and the global equation module in COMSOL Multiphysics version 5.2a. The electrical parameters to simulate the YBCO foam sample use the power law E(J) = E c (J/J c ) n with the parameters E c = 1 µV/cm, n = 20, and a critical current density J c = 1000 A/mm 2 , corresponding to the measurements on foam struts of Ref.…”

Section: First Modelling Of Field Cooling and Trappingmentioning

confidence: 99%

Microstructural Parameters for Modelling of Superconducting Foams

Koblischka

Koblischka-Veneva

Nouailhetas

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

Superconducting YBa2Cu3Oy (YBCO) foams were prepared using commercial open-cell, polyurethane foams as starting material to form ceramic Y2BaCuO5 (Y-211) foams which are then converted into superconducting YBCO by using the infiltration growth process. For modelling the superconducting and mechanical properties of the foam samples, a Kelvin-type cell may be employed as a first approach like done in the literature for pure polyurethane foams. However, for a refined model of a superconducting foam sample, the real sample structure must be considered. Thus, a proper description of the specific microstructure of the superconducting YBCO foams is required. A variety of parameters including the cell size and shape, the window size and shape, the length and shape of the foam struts or ligaments and the respective angles of intersection are used to describe the real foam structure. To obtain a set of reliable data, YBCO foam samples were investigated using optical microscopy, SEM and electron backscatter diffraction (EBSD). The detailed investigation of the foam microstructure reveals not only the differences to the polymeric foams used as base material, but also gives insight to details of the infiltration growth process via the increased surface amount in a foam sample.

show abstract

2-D Numerical Modeling of a Bulk HTS Magnetization Based on <bold>H</bold> Formulation Coupled With Electrical Circuit

Cited by 9 publications

References 12 publications

Microstructural Parameters for Modelling of Superconducting Foams

Microstructural Parameters for Modelling of Superconducting Foams

Alternating Current Loss of Superconductors Applied to Superconducting Electrical Machines

Microstructural Parameters for Modelling of Superconducting Foams

Contact Info

Product

Resources

About