Quench in bulk HTS materials - application to the fault current limiter

We report theoretical and experimental studies on the use of bulk Bi or Y m aterials for fault current limiters. The materials are compared in terms of required volume, recuperation time,.... The problem of the unavoidable hot spots in high J(c) materials is discussed. A moderate J(c), and an operati on near T-c, make the quench effective and non-destructive for YBCO single domain bars or meanders. Experiments carried out above 90 K are reported. Y BCO doping with MgO shows good opportunities to operate at 77 K for example .