Dynamic resistance and voltage response of a REBCO bifilar stack under perpendicular DC biased AC magnetic fields

Abstract Dynamic resistance of REBCO coated conductors (CCs) is a key parameter in many high-temperature superconductor applications where CCs carry DC currents exposed to AC and magnetic fields, such as field-triggered persistent current switches, flux pumps, fault limiters. In this work, dynamic voltage has been studied via experiments FEM simulations bifilar stack at 77 K under combined fields with different magnitudes, frequencies, waveforms. Our results show some distinct features from those pure fields. With increasing exhibits an obvious linearity applied becomes less dependent on the field frequency. The fundamental frequency same that which completely differs case doubles. For first time, instantaneous threshold (Bth) values are obtained voltage, substantically field-increasing field-decreasing process. These differences attributed dominant role determining critical superconductor, significantly dwarfs influence new discoveries may help researchers better understand electromagnetism be useful for relevant applications.