Impact of Superconducting Fault Current Limiters on the Coordination Between Generator Distance Phase Backup Protection and Generator Capability Curves

In this paper, investigations are carried out to explore the impact of superconducting fault current limiters installed in the transmission system on the coordination between the generator distance phase backup protection (function 21) and the generator capability curve. The results of these investigations have shown that both the resistive and inductive type superconducting fault current limiters have an adverse effect on this coordination. Such an impact varies according to the fault type, the fault location, and the generator loading. The dynamic simulations of a test benchmark have been conducted by using the PSCAD/EMTDC software.