Development of the design factor for the 1phase module of 6.6kV/200A class resistive superconducting fault current limiter

In these days, there is a demand to develop fault current limiters (FCL) to reduce excessive fault current and protect electrical equipments which are installed in transmission and distribution power systems. We considered the resistive superconducting FCLs among the various kinds of FCL. In this study, in order to develop the resistive superconducting FCL of 6.6 kV 200 A 3Φ, we designed the new mask pattern for etching YBCO films by means of numerical analysis method, current limiting experiments and visualization of bubbles in films and investigated dielectric performance of the designed mask by using electrostatic numerical analysis method and breakdown experiments. We visualized the bubble propagation characteristics of etched films and selected the thickness of the gold layer in superconducting elements. We etched YBCO films by using the newly designed mask, connected the etched films in series and in parallel, and designed 1phase module for the 6.6 kV resistive SFCL and then we observed the current limiting characteristics of the module.