Current Limiting Characteristics of Transformer Type HTS Superconducting Fault Current Limiter with Rewound Structure

A transformer type SCFCL of HTS wire with rewound structure has a primary coil of BSCCO wire connected to a power system and has a secondary coil of also BSCCO wire short-circuited. Both HTS coils were wound co-axially with rewound structure to get longer wire, that is, larger resistance at the normal state. The rewound structure offers greater flexibility in the design of the inductance and resistance of the SCFCL. It was experimentally confirmed that the SCFCL gives an inductive limiting impedance for smaller fault current while the only secondary wire transits to normal state and for larger fault current, it can give a resistive component additively by the normal transition of the primary wire. The current limiting characteristics of the proposed SCFCL were discussed by experimental results. Excellent recovery characteristics, that is, the recovery under load operation and repetitive limiting operation were confirmed experimentally.