Numerical Evaluation of Circuit Model for Fast Computational Analysis of Resonant Wireless Power Transfer System

This article proposes a circuit model (CM) to calculate the current along printed coils used in resonant wireless power transfer (RWPT). It considers a system composed of a metamaterial and two coplanar coils, transmitter (Tx) and receiver (Rx), respectively. First, a CM for the system is presented. Then, an analytical model is proposed to calculate the self-inductance of printed inductors, their characteristic resistance, and the mutual inductance between coils. The proposed formulation for calculating the mutual inductance between inductors is based on Neumann’s formula. The practical results validate the model precision, obtaining a maximum deviation of ≈8%, 3%, and 3%, respectively. Due to the generality of this approach, it can also be applied to more complex structures, such as metasurfaces (MTS). The proposed 3-D models proved to be ideal for modeling the printed inductor. Furthermore, this model proved to be computationally more efficient for analyzing large systems when compared with commercial full-wave simulation software, with a reduction in the computational time larger than three orders of magnitude.

I. Introduction

Aresonant wireless power transfer (RWPT) system is one of the inductively coupled wireless power transmission techniques. There are several approaches in which metamaterials are used between the wireless power link to increase transmission efficiency or focus the magnetic field [1].