Quench characteristics of HTSC elements in integrated three-phase flux-lock type SFCL according to ground-fault types

Abstract

The quench characteristics of high-TC superconducting (HTSC) elements in the integrated three-phase flux-lock type superconducting fault current limiter (SFCL), which consisted of HTSC elements and a three-phase flux-lock reactor wound on one iron core with the same turn’s ratio between coil 1 and coil 2 in each single phase, were investigated. In a normal condition, the magnetic flux generated in the iron core is zero because the magnetic flux generated between two coils of each single phase is canceled out. However, unlike other three-phase SFCL with three isolated iron cores, the integrated three-phase flux-lock type SFCL showed the different fault current limiting characteristics for the three-phase faults such as the single line-to-ground fault, the double line-to-ground fault, the line-to-line fault and the triple line-to-ground fault. In addition, the power burden of HTSC elements comprising the integrated three-phase flux-lock type SFCL can be decreased.In this paper, we investigated the quench characteristics of HTSC elements in the integrated three-phase flux-lock type SFCL according to three-phase ground fault types. Through the experiments for the fault current limiting characteristics of this type SFCL according to three-phase ground fault types, the quench characteristics of HTSC elements were analyzed and compared with those of three-phase resistive type SFCL.