AC LOSS ANALYSIS ON HIGH-TEMPERATURE SUPERCONDUCTORS WITH FINITE THICKNESS AND ARBITRARY MAGNETIC-FIELD DEPENDENT VOLTAGE-CURRENT RELATION

A numerical model is developed for the current distribution in high-te mperature superconductors (HTS conductors)subjected to self and applie d field. This analysis is based on the two-dimensional Poisson equatio n for the vector potential. The vector potential is rewritten into an equation of motion for the current density J. The finite thickness of the conductor and the n-power law electric field-current density relat ions (E-J relations)of the conductor are included in the model. The ma gnetic field dependence of critical current density J(c) is also inclu ded in this E-J relation. The self-field loss obtained with this analy sis has good agreement with experimental data. Also the effects of asp ect ratio and n value on ac loss are pointed out to be important on th e ac loss. (C) 1998 American Institute of Physics. [S0021-8979(98)0702 2-4].