Analysis of Wireless Energy Transfer System Based on 3-D Finite Element Method Including Displacement Current

摘要

With the development of electronic technology, there has been increasing interests in research of wireless power transfer method. The finite element method (FEM) is a powerful tool for the numerical simulation of the system. Generally, the resonant frequency of the wireless power transfer system can be up to several megahertz. Due to the presence of inductance and capacitance in the system, eddy current and displacement current become two essential parts in the electromagnetic field distribution. The problem to be addressed is between low and high frequencies. Conventional low frequency method cannot include displacement current, while common high frequency method cannot couple circuit equations with field equations. In this paper, the Maxwell's equations with displacement current are used to describe the Witricity system. It has the potential to couple the circuit equations directly. Through numerical electromagnetic field analysis, the current induced in the receiver loop and the efficiency of the transfer power between the sender and receiver loops can be easily obtained.