Experimental Study on the Dynamic Resistance of HTS REBCO Coated Conductor Tape

When a perpendicular AC magnetic field is applied to type-II high-temperature superconductors carrying direct current (DC), a DC voltage will be induced, which is called the dynamic resistance effect. This work investigates the dynamic resistance of REBCO coated conductors under various operating conditions. An experimental platform was developed to measure the dynamic resistance of a high-temperature superconducting (HTS) tape under different DC current ratios, magnetic field amplitudes, and frequencies. A finite element model based on H-formulation was built using COMSOL Multiphysics to simulate the dynamic resistance behaviors. The simulation results agree well with experimental measurements results and empirical formulas, supporting the accuracy of the numerical model. The results indicate that dynamic resistance will increase with the rise of DC current and the amplitude of the applied AC magnetic field. Furthermore, we compared the dynamic resistance of multi-filamentary REBCO tapes with those of standard REBCO tapes. The multifilament design can effectively reduce dynamic resistance. These results will help design and develop low-loss HTS excitation windings for high temperature superconducting electrical machines.