AC loss measurement with a phase difference between current and applied magnetic field

Total AC losses in multi-filamentary, silver-sheathed Bi/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub y/ (Bi-2223) tape were measured as functions of transport current, applied magnetic field and frequency by electromagnetic and calorimetric methods. Results of both methods agree well with each other. The calorimetric method was employed to investigate the effect of the phase difference between transport current and applied field, /spl Delta//spl phi/, on total AC loss. Total loss changes significantly with /spl Delta//spl phi/ when applied magnetic field is perpendicular to the surface of the sample. The effect of /spl Delta//spl phi/ on total loss in parallel magnetic applied field is smaller.