Effects of frequencies and temperatures on self-field loss for Ag/Bi-2223 tapes

Self-field loss of Ag/Bi-2223 tape conductors cooled by using the GM cryocooler in the temperature range of 60-100 K was studied in the conditions of various frequencies (10-500 Hz) of AC transport current. Self-field loss per cycle and per length divided by a square of critical current, I-c(2), decreased with increase of the frequency and with decrease of temperature unlike Norris' equation. Especially, the loss reduction ratio by frequency change decreased with increase in temperature. To confirm difference in loss dependencies between the calculated and the experimental results, we also achieved the numerical analysis based on Maxwell's equations using a finite difference method. The analysis results were mostly in agreement with the experimental results. (C) 2001 Elsevier Science B.V. All rights reserved.