The current density distribution in HTS tapes for power transmission applications plays a key role for the determination of the conductor dissipation both in normal and in overload conditions, as occurring for example during transmission lines faults. We have tested the response of Ag/Bi2223 tapes in dc and ac self field transport current in order to determine the repartition of current between the superconducting material and the silver sheath, in particular in the high current range. The experimental results are compared with the results of a numerical calculation model able to determine the tapes self-field current density distribution both above and below Ic. The same model is also used to calculate the tape's AC losses. The results are compared with the measured values.
