Leakage magnetic field analysis and magnetic circuit modeling of a saturated iron-core superconducting fault current limiter

In this paper, the basic structure of saturated iron-core superconducting fault current limiter (SISFCL) was analyzed and 3D model of the limiter whose superconducting coil was comprised of 44 double pancake rings was established. The magnetic flux leakage distribution of the limiter was calculated by using the finite element method (FEM), the distribution characteristics of leakage magnetic field was analyzed. The equivalent magnetic circuit model was built with magnetic field division method with the magnetic flux leakage. The simulation was compared with the test results. The results show that the equivalent magnetic circuit model is valid. This has a certain reference value for the design and application of SISFCL. (authors)