Protective Relay Tests of Hybrid SFCLs in a Korean Distribution Power System Using RTDS

A study on protective relay systems is one of the important technical issues concerning power systems that use Superconducting Fault Current Limiters (SFCL). We used a Real Time Digital Simulator (RTDS) in order to study the true interaction of the protection system with the power systems. RTDS modeling of SFCL is necessary to obtain detailed protective relay tests. In this paper, we developed an analysis model using RTDS in order to study the transient behavior of a 22.9 kV hybrid SFCL and performed closed-loop testing on a protective relay in a distribution power system using the developed SFCL model. The model uses an operation mechanism of the real SFCL. The 22.9 kV hybrid SFCL is under development by LSIS (LS Industrial Systems Co., Ltd.) and KEPRI (Korea Electric Power Research Institute) in Korea. The parameters of the model are based on the test data from the real SFCL. Power system planners and operators will be able to solve the problems that are expected in the application of SFCLs to power systems by using these protective relay testing results.