Electrical Characteristics of 2G HTS Tapes Under DC Current With AC Ripple

Electrical behavior and AC losses of Second Generation High Temperature Superconducting (2G HTS) tape were characterized under AC ripple current superimposed on a DC offset current. The maximum safe transport current and ac losses were measured as functions of AC ripple current amplitude and frequency. It was observed that the frequency of ripple current does not significantly affect the maximum safe transport current. For total DC and AC current less than the critical current, the extent of AC loss does not depend on the magnitude of DC offset current. The losses, however, increase with DC offset current for total current value exceeding the critical current because of increased resistance caused by the onset of quench of the tape to normal state.