Effect of Peak Current Limiting in Series-Connection SFCL With Two Magnetically Coupled Circuits Using E-I Core

In this paper, we proposed a series-connection-type superconducting fault current limiter (SFCL) that can prevent the internal magnetic flux generation of cores during normal operation and prevent the saturation of cores due to a sudden magnetic flux generation at the initial stage of fault occurrence while limiting the peak current. The proposed SFCL does not mediate two cores, as previously reported, but mediates a single E-I core having a configuration of two magnetically coupled circuits using the first, second, and third windings. The other magnetic path is formed by the third coil and the other superconducting element isolated from two coils. Through a short-circuit experiment, we analyzed the operating status of the two superconducting elements and peak current limiting properties according to the amplitude of the fault current before and after the failure. Furthermore, the peak current limiting characteristics according to the winding directions, as well as the current and the voltage of each coil, were compared and analyzed.