Quenching behaviour of superconductors in an inductive fault current limiter

Earlier papers introduced a new form of inductive superconducting Fault Cur rent Limiter (FCL) in which the primary and secondary windings were interle aved symmetrically, producing current sharing in the multiplicity of second ary coils. A new FC. which employs similar structure but in a higher rating has been designed and constructed, The new FCL has eight series connected primary coils interleaving with at least eight isolated secondary supercond uctor rings around a toroidal iron core. Investigation of this FCL when car rying different number of superconductor rings has showed the ability to re duce the leakage fields around the windings hence improving the current rat ing of the FCL by increasing the number of superconductor rings in the FCL, However, being isolated each superconductor ring has different switching p rofile as a result of the development of normal regime resistance at differ ent current values, A new way of characterising this non-uniform quenching behaviour of the superconductors in the FCL, as the fault occurs is reporte d.