Improvement of YBCO Superconductor Magnetic Shielding by Using Multiple Bulks

• Published in: Journal of superconductivity and novel magnetism Vol. 27; no. 4; pp. 903 - 907
• Main Authors: Douine, B., Male, G., Lubin, T., Mezani, S., Leveque, J., Berger, K.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-04-2014; Springer Verlag
• Subjects: Characterization and Evaluation of Materials; Computer Science; COMPUTER SIMULATION; Condensed Matter; Condensed Matter Physics; COPPER OXIDE; CURRENT DENSITY; Electric power; Electromagnetism; Engineering Sciences; MAGNETIC FIELD; Magnetic fields; Magnetic Materials; Magnetic shielding; Magnetism; Modeling and Simulation; PELLETS; Physics; Physics and Astronomy; Review Paper; Screening; Shields; SHIELDS (MAGNETIC); Simulation; Strongly Correlated Systems; SUPERCONDUCTIVITY; SUPERCONDUCTORS; YBCO superconductors; YTTRIUM OXIDE; Superconducting shielding; HTS bulks; Superconducting motor
• ISSN: 1557-1939; 1557-1947
• DOI: 10.1007/s10948-013-2460-5

HTS bulks present a high critical current density which can be used as magnetic shields. Previous works showed that BSCCO bulks can screen magnetic fields up to 0.1 T. For large scale applications like electrical machines, stronger magnetic field is usually needed. In so doing, (RE)BCO materials are more suitable since they can shield much higher magnetic fields. Another key issue concerns the size of the bulks. Nowadays, it is possible to manufacture 150-mm diameter class cylindrical YBCO bulk. In order to get larger magnetic shielding areas, multiple bulk superconductors should be arrayed and stacked in layers. This paper presents experimental results on screening performances of layered YBCO pellets. These results are compared with 2D simulations. The experiments are carried out at 77 K under external magnetic fields of 150 mT. Different topologies are considered: single-layer configuration with 9 square pellets and double-layer configuration with respectively 9 and 4 square pellets. Experimental and simulation results show that a checkerboard of one layer configuration does not fully shield the external magnetic field. Improved shielding properties are obtained when the double-layer configuration is used.