Magnetization and Power Losses Characteristics Due to Variation in the Number of Windings of a Bridge Type SFCL With Double HTSC Elements

Superconducting fault current limiters (SFCLs) are emerging as an alternative to limit fault current in AC and DC power systems. SFCLs can perform faster current limiting operation and automatic fault current detection and recovery, regardless of the type of fault. In this paper, a laboratory-scale prototype SFCL was fabricated and analyzed for its magnetization characteristics due to the magnetizing current according to the change of the number of windings in pairs. This bridge type SFCL consists of two windings and two high-Tc superconducting (HTSC) elements on one iron core. When the number of windings of the two coils were changed in pairs, the variation of the induced voltage and Joule losses due to the magnetizing current, magnetic flux in each winding, and power losses for the bridge type SFCL were compared with each other. Through comparative analysis, it was confirmed that the size of the number of turns should be considered to reduce the power losses of SFCL while effectively limiting the fault current during the fault cycle.