Coordination of overcurrent protection relays in networks with superconducting fault current limiters

The paper concerns coordination of overcurrent (OC) protection relays in power networks with superconducting fault current limiters (SFCL). At the beginning, information about designed SFCL and conditions that ensure overcurrent protection coordination are presented. Next, settings of the overcurrent relays were determined for a sample network with SFCL model installed. The considered HV/MV power system was modeled in the ATP/EMTP software and the effects of OC relays coordination was analyzed. At the end, conclusions from conducted studies and resulting guidelines for protection coordination are provided.