TY - JOUR
T1 - Trapped Field Characteristic of YBCO Bulk in AC External Magnetic Field
AU - Ueda, Hiroshi
AU - Ishiyama, Atsushi
AU - Morisaki, Tohru
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2004
Y1 - 2004
N2 - Trapped field characteristics are one of the key factors in the application of high-temperature superconducting bulk, such as magnetic levitation systems, motors, bulk magnets and so on. The immutable trapped field is required in superconducting bulk applications as a quasi-permanent magnet, however, the trapped field is influenced and changed by a time-varying external magnetic field in a realistic operational environment of electrical devices. This means that shielding current distribution within the bulk is changed by the time-varying magnetic field and the transient magnetic flux movement results in temperature rise and finally reduction of the trapped field. In this study, we observed the abrupt reduction of the trapped field for the external AC magnetic field in the range of frequency up to 50 Hz. And we also performed the numerical simulation using a newly developed computer program based on the finite element method (FEM). In the simulation program, the voltage-current (E–J) characteristics, which depend on the irreversibility temperature are taken into account. From these results, it can be considered that the abrupt reduction of the trapped field is caused by the temperature rise due to AC loss.
AB - Trapped field characteristics are one of the key factors in the application of high-temperature superconducting bulk, such as magnetic levitation systems, motors, bulk magnets and so on. The immutable trapped field is required in superconducting bulk applications as a quasi-permanent magnet, however, the trapped field is influenced and changed by a time-varying external magnetic field in a realistic operational environment of electrical devices. This means that shielding current distribution within the bulk is changed by the time-varying magnetic field and the transient magnetic flux movement results in temperature rise and finally reduction of the trapped field. In this study, we observed the abrupt reduction of the trapped field for the external AC magnetic field in the range of frequency up to 50 Hz. And we also performed the numerical simulation using a newly developed computer program based on the finite element method (FEM). In the simulation program, the voltage-current (E–J) characteristics, which depend on the irreversibility temperature are taken into account. From these results, it can be considered that the abrupt reduction of the trapped field is caused by the temperature rise due to AC loss.
KW - finite element method
KW - high-temperature bulk superconductor
KW - trapped field attenuation
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U2 - 10.1541/ieejpes.124.1357
DO - 10.1541/ieejpes.124.1357
M3 - Article
AN - SCOPUS:33646759126
VL - 124
SP - 1357
EP - 1364
JO - IEEJ Transactions on Power and Energy
JF - IEEJ Transactions on Power and Energy
SN - 0385-4213
IS - 11
ER -