Comparison of Initial Current Limiting Performance of Two Inductive Superconducting Fault Current Limiters With Different Electrical Coupling Between Cores and Coils

It is possible to improve the performance of the superconducting fault current limiters and to apply power system as a method for reducing the volume and weight of the superconducting fault current limiters using iron core and coil. This study thus manufactured a superconducting current limiting element using a coated conductor with high specific resistance, and applied it to two models with an iron core and coil (a model consisting of three separated iron cores and coils and a model integrating three coils through one iron core) for the comparison and analysis of the current limiting characteristics. Of the two aforementioned models, the separate-iron-core/coil model with additive polarity wiring offered a higher current limiting rate, but under each wiring condition (subtractive polarity and additive polarity wirings), the two models' current limiting rates were found not to be very different. The superconducting current limiting element's thermal strain was determined to be smaller in the integrated model than in the separate-iron-core/coil model, but the integrated model created quench resistance of the superconducting current limiting element at the sound phase (S phase), suggesting that the result increased the critical current of the superconducting current limiting element. Further studies should be done, however, through the structural change of the integrated model.