Improvement of Current Limiting Capability of HTSC Elements in Hybrid Type SFCL

We investigated that the current limiting capability of the high- superconducting (HTSC) elements comprising the hybrid type superconducting fault current limiter (SFCL) could be improved with lower power burden for each HTSC element and higher limiting impedance of the SFCL by adjusting the number of turns of the secondary winding. As estimable parameters to confirm it, the resistance and the power loss generated in each HTSC element and the limiting impedance of the SFCL were derived from the electrical equivalent circuit. It was confirmed through the analysis based on the fault current limiting experiments that the power burden of HTSC element in the hybrid type SFCL could be decreased with higher limiting impedance of the SFCL by using a smaller number of turns of secondary windings.