Experimental Study on the Current Limiting Characteristics of a Saturated Iron-Core Superconducting Fault Current Limiter in DC Power Systems

Several recent studies have proposed a conceptual design of a saturated iron-core superconducting fault current limiter (SI-SFCL) for DC power systems, but experimental studies to verify its operating characteristics and performance have not yet been conducted. In this paper, a laboratory-scale SI-SFCL was designed and tested to operate in a 500 V, 50 A DC power system. First, the detailed configuration, specifications, and hardware manufacturing contents of the SI-SFCL were presented, and then an experimental circuit was developed and installed for the performance test of the SI-SFCL in normal operation and failure conditions. A 3D finite element method model was constructed to compare the simulation results and experimental results for the operating function of the SI-SFCL. Without the SI-SFCL, the maximum fault current level was 500 A, as a result, the SI-SFCL has a large current limit function, which can reduce the magnitude of the fault current up to the design target value of 73.6%. The results obtained in this study can be effectively applied to large-scale SI-SFCL development studies for HVDC power systems.