Study on a Series Resistive SFCL to Improve Power System Transient Stability: Modeling, Simulation, and Experimental Verification

This paper presents a study to determine the optimal resistive value of a superconducting fault-current limiter (SFCL) for enhancing the transient stability of a power system more effectively. A resistive type of SFCL, which provides quick system protection, is modeled. Then, the optimal resistive value of the SFCL connected in series with a transmission line during a short-circuit fault is systematically determined by applying the equal-area criterion based on the power-angle curves. To verify the effectiveness of the optimal value of the proposed SFCL for reducing the value of fault current, several case studies are carried out by both simulation and experimental tests, particularly including the 220-V/300-A-scale laboratory and 13.2-kV/630-A-scale distribution system hardware tests. The results show that the optimal resistive value of the SFCL determined by the proposed method improves effectively the transient stability and damping performances during a fault over the other values determined by an ad hoc approach.