CURRENT LIMITER FOR ELECTRICAL DISTRIBUTION SYSTEMS POWERGRID Europe, Milano 3-5 Giugno 2008 Luciano Martini*, Marco Bocchi*, Cesare Ravetta**, Andrea Ruffini** *CESI RICERCA *AEM Elettricità S.p.A As electric power systems grow and become more interconnected, the fault current levels increase. Conventionally, handling these increasing fault currents often requires the costly replacement of substation equipment or the imposition of changes in the network configuration. Therefore there is a considerable interest in devices which are able to limit fault currents. The Superconducting Fault Current Limiter (SFCL) is a device which, on the fault occurrence, limits, in a crucial branch of the circuit and within few milliseconds, the short-circuit currents I SC to lower levels, so that no component or underrated switching equipment in the system becomes overloaded but can be operated safety. In this work, we report on design and short-circuit simulations of a 9 kV / 15 MVA-class SFCL for distribution system applications based on both first and second generation High Temperature Superconductors (HTS). Fault simulation results for two case studies of practical interest are reported, discussed, and deeply analyzed.