Physical and numerical models of superconducting fault current limiters

The physical and numerical models of the inductive type superconducting fault current limiter (SFCL) were made. The physical models. consist of superconducting Bi2223 tubes (diameter = 0.059 in, height = 0.05 m and critical current at 77 K = 625 A), iron cores (cross-section area = 0.02 in X 0.02 in and 0.02 in x 0.03 in) and the plastic cryostat with copper, primary winding (236 turns). The voltage-current characteristics of these physical models were used for verification of the geometry and properties of regions in numerical model of FCL. The numerical model using the magnetodynamics physical domain of the CAD package FLUX2D coupled with circuit equations was used to analyze the influence of selected parameters on SFCL voltage-current characteristics. The paper shows that the changes of the iron core and the superconducting tube geometry influence these characteristics significantly.