Inductance Interpolation-Based Fast Design and Optimization Methodology for Wireless Power Transfer Systems

In designing wireless power transfer (WPT) systems, the finite element method (FEM) is usually the interface between the physical entities of the WPT windings and the electrical parameters of the windings such as the inductances and the parasitic resistances. However, this interface is unidirectional, i.e., by knowing the physical parameters of the windings, the electrical parameters can be obtained using the FEM, but not vice-versa. Thus, two challenges are introduced. One is to locate the possible solutions for the physical variables of the windings when the required mutual inductance(s) are determined by the desired characteristics of the WPT system. The other is to search for the optimal solution among the possible ones. Conventionally, the trial-and-error method is adopted to obtain a near-optimal solution, which is time-consuming or even impossible when designing systems with more than two winding-resonators. This article proposes a unique design methodology using the inductance interpolation based approach for WPT systems. With this method, running ONE FEM simulation is sufficient to obtain the required data set for winding design and optimization. The optimization of a three-winding WPT system using the proposed method is provided. The experimental prototype is built, and the measured results are obtained to verify the optimization process.