| Title |
Increase of Operational Current in a SFCL using Series or Parallel Coupling of Coils |
| Keywords |
Fault Current Limiting Characteristics ; Superconducting Fault Current Limiter(SFCL) ; Magnetic Coupling ; Inductance Ratio |
| Abstract |
The fault current limiting characteristics of superconducting fault current limiter (SFCL) using magnetic coupling of two coils were investigated. This SFCL consists of a high-TC superconducting (HTSC) element and two coils with series or parallel connection on the same iron. In normal time, the inner magnetic fluxes generated by two coils are canceled in case that the HTSC element keeps superconducting state. However, in case that the resistance of the HTSC element happens by a short-circuit, the magnetic fluxes, not cancelled, induce the voltages across two coils and the fault current can be limited by the impedance of this SFCL. This SFCL has the merit that the operational current of SFCL can be increased higher than the critical current of the superconducting element by adjusting the inductance ratio between two coils. To confirm its operation, the circuit for the fault simulation was constructed. From the measured voltage and current of the SFCL, it was confirmed that the operating current of this SFCL increased more than that of HTSC element"s independent operation. |