BEM computation of the internal impedance of air-core inductors enforcing high-order surface impedance boundary conditions

The internal impedance of an axisymmetric air-core inductor is computed by the Boundary Element Method (BEM) coupled with high-order surface impedance boundary conditions (SIBCs), which considers the curvature of the cross-sections of the conductors. The proposed method is based on the Perturbation Technique (PT) and provides accurate results in a wide frequency range by solving only once the BEM formulation. A flat spiral air-core inductor is considered as a test case and the Finite Element Method (FEM) without SIBC is used to obtain the reference results.