Magnetizing Characteristics of a Flux-Coupling Type SFCL With Two Magnetic Flux Paths Using Its Third Winding

Abstract

A flux-coupling type superconducting fault current limiter (SFCL) was fabricated to have two magnetic flux paths using an E-I iron core, and the winding direction between the two main coils was a subtractive polarity winding. During the fault period, peak current limiting characteristics and voltage waveforms between the primary and secondary windings were compared according to the parallel and series configurations. In addition, flux linkages and instantaneous powers characteristics were analyzed by connecting the two main coils in parallel and in series. When the two main coils were connected in parallel and in series, the magnetizing power area and the flux linkage's operating range related to the magnetic flux energy accumulated in the iron core were compared with each other, depending on the magnetization current increase or decrease.