15 ｋVA급 저항형 초전도 전류제한기의 전류제한특성 = Characteristics of 15ｋVA Resistive Superconducting Fault Current Limiters

다국어 초록 (Multilingual Abstract)

We investigated resistive superconducting fault current limiters (SFCLs) fabricated using YBCO thin films on 2-inch diameter sapphire substrates. Nearly identical SFCL units were prepared and tested. The units were connected in series and parallel to increase the current and voltage ratings. A serial connection of the units showed significantly unbalanced power dissipation between the units. This imbalance was removed by introducing a shunt resistor to the firstly quenched unit. Parallel connection of the units increased the current rating. An SFCL module of 4 units in parallel, each of which has minimum quench current 25 A_(peak), was produced and successfully tested at a 220 V_(rms) circuit. From the resistance increase, we estimated that the film temperature increases to 200 K in 5 msec, and 300 K in 120 msec. Successive quenches revealed that this system is stable without degradation in the current limiting capability under such thermal shocks as quenches at 220 V_(rms).