Design of 6.6 kV, 100 A saturated DC reactor type superconducting fault current limiter

Proposed saturated DC reactor type superconducting fault current limiter (SFCL) was designed and fabricated. The rated value was 100 V and 10 A for small scale experiment. The relationships between the one-turn voltage and the cross section of the core, the inductance value are obtained, The optimized cross section of the core was 90 mm x 45 mm under restriction of the core manufacturer. The core material was ultra fine grain steel named FINEMET(R) FT-3H. The number of main winding was 100 turn and that of control winding was also 100 turn. The wires are NbTi superconductor with different filament diameter. We enhanced this design scheme to 6.6 kV, 100 A SFCL. The core cross section size and core gap and core length of 6.6 kV design are presented.