Analysis of AC loss characteristics of HTS coils with various cross-sections

An analytical study of AC loss characteristics of a high temperature superconducting coil wound by a Bi2223/Ag tape is presented in this paper. The AC loss in the high temperature superconducting coil wound by Bi2223/Ag tape was numerically calculated by using the measured DC data of the tape. The calculated AC loss was compared with the measured AC loss in the Bi2223 HTS coil obtained in the previous study. For the comparison of the measured and calculated AC losses, the mechanical loss was subtracted from the measured total loss data. The calculated AC losses were compared with the measured AC losses in the coil, producing rather good agreements. The relation between the AC loss characteristics in the HTS coil and shape of coil cross-section was numerically studied. A possible way to reduce the AC loss in the HTS coil was also presented and discussed.