Improvement of Recloser-Fuse Operations and Coordination in a Power Distribution System With SFCL

In this paper, we describes how to coordinate between recloser and fuse in power distribution system with superconducting fault current limiters (SFCL). The recloser and fuses are the main overcurrent protective devices in power distribution system. Universally, to protect against permanent faults, fuses are installed on overhead feeder laterals and the reclosers as a backup protection against temporary faults remove many unnecessary outages. Here, the recloser is set to trip using TCC curve for a temporary fault before any of the fuses can melt. If the fault is a permanent fault, the fuse has to melt just before the last delay trip of the recloser. However, the application of a resistive SFCL in power distribution system affects the recloser-fuse operation and coordination as decreased fault currents. In case that when a permanent fault occurs, the recloser could be locked-out after the last delay trip before the fuses operate. Therefore, to solve these cases, we performed experiments which are the recloser-fuse operation and coordination in the modeled power distribution system with the SFCL. Based on the experimental verification, we improved to coordinate the recloser-fuse in power distribution system with SFCL.