Electromagnetic Thermal Analysis on Variable Resistive-Type Superconducting Fault Current Limiter

Resistive-type superconducting fault current limiters (R-SFCLs) have garnered attention for their straightforward design and effective current-limiting capabilities in power systems. Nevertheless, a significant limitation lies in the prompt recovery from current constraints. Addressing this issue, the research introduces a 10 kV superconducting fault current limiter (VR-SFCL) characterized by variable resistive properties. Utilizing a COMSOL simulation featuring finite element analysis for electromagnetic-thermal interactions with a 2D superconductor model, the model takes into account the anisotropic E-J property, and the Joule heat equation, and contains the complete critical parameters such as the thickness of the ag layer and YBCO layer in superconducting tapes to ensure higher accuracy compared to the simplified traditional simulation. At a 10 kV/630 A system, whose peak fault currents range from 5 to 25 kA, simulation and experimental results show that VR-SFCL can reduce the superconducting layer's temperature by 5 K to 10 K, reduce recovery time by 50%, and the current limiting resistance increases to 3 times of the R-SFCL to satisfy the reclosing requirements of the system.