Development of high temperature superconducting fault current limiting transformer (HT/sub c/-SFCLT) with Bi2212 bulk coil

We have been developing a high temperature superconducting fault current limiting transformer (HT/sub c/-SFCLT) with functions of both superconducting transformer in normal operating condition and superconducting fault current limiter in fault condition. The ratings of the developed HT/sub c/ SFCLT are 3-phase, 6.25 kVA, 275/105 V. The secondary coil consists of melt cast processed (MCP)-BSCCO2212/CuNi composite bulk monofilar coils, whereas the primary coil is composed of a copper coil, both of which are immersed in liquid nitrogen bath together with the iron core. Experimental results revealed the operational feasibility of HT/sub c/-SFCLT through no-load and short-circuit tests, current limiting test and recovery test.