Quench and Recovery Characteristics of SFCL Based on Double-Sided YBCO Thin Films

In previous studies, we have preliminarily verified the feasibility of resistive superconducting fault current limiters (SFCLs) by using double-sided thin films. However, there are still many details that need to further research on double-sided thin films. In this present study, we fabricated two SFCL components juxtaposed on two sides of 2-in diameter sapphire substrates, coated with a gold layer and patterned into meander lines by photolithography. The double-sided SFCL components in serial connection were subjected to the ac fault currents, and their quench and recovery characteristics were investigated at various source voltages. From the experiments results, it was revealed that the double-sided configuration induced simultaneous quench and recovery between the components, and the temperature distribution in double-sided SFCL components was nearly close during quench and recovery. These results can be interpreted with the thermal interaction between top and bottom SFCL components by the sapphire substrates. The thermal effect of electrodes significantly affected the temperature distribution during quench and recovery. In addition, in overcurrent experiments, we defined the concept of perpendicular quench propagation to explain the rapid limitation of fault current at the beginning of short circuit and to optimize the structure of double-sided SFCL module.