Modeling of Dense Windings for Resonant Wireless Power Transfer by an Integral Equation Formulation

A full-wave integral equation scheme for modeling resonant coils applied in wireless power transfer systems is presented. An A - Phi formulation is applied with current and charge densities on the wire surface as unknowns. The method overcomes the limitation of the "thin-wire approximation" as it enables the unknowns to vary on the wire surface. Thus, proximity effects (that typically emerge when modeling dense windings) are taken into account. The numerical implementation of the formulation has smaller computation cost than, for example, finite element methods. The proposed scheme is tested against closed-form solutions and alternative simulations.