Temperature dependence of transport AC losses in Bi-2223/Ag multifilamentary tapes

Temperature dependence of transport ac losses in two Bi-2223/Ag multifilamentary tapes with different de current-voltage characteristics was measured using a lack-in technique at power frequencies. At each temperature, different criteria for critical current determination were used. Comparisons of normalised ac losses with predictions of theoretical models for a tape with elliptical cross-section and a thin strip were made. It was found that the form of the current-voltage characteristic and the critical current criterion play an important role in comparison with theoretical data. A new normalisation procedure of ac loss data is proposed. (C) 1998 Elsevier Science B.V, All rights reserved.