Ramp rate dependence of E-I characteristics in Bi2223/Ag HTS tapes

We have been studying the ramp rate dependence csf the E-I characteristics under self-magnetic field in Bi2223/Ag HTS tapes at 77 K. In this paper, we have examined an experimental result and a numerical analysis. Experimenta lly, we applied about 70 A, which is about twice that of the I, into Bi2223 /Ag HTS tapes at ramp rates of 14 kA/s to 1.4 MA/s. When the ramp rate incr eases, the electric field of the E-I characteristics increases. The experim ental results were compared to that of numerical analysis using finite elem ent method. As a result, when the ramp rate increases, the transport curren t concentrates to the outer filaments. Therefore, the skin effect occurs fo r the higher ramp rate, and eddy current loss in Ag sheath increases. (C) 2 001 Elsevier Science Ltd. All rights reserved.