Quasi static approximation of wireless power transfer systems through coupled resonance and improving power transfer efficiency

Abstract

The aim of the study is to transfer power wirelessly through the resonance of the source and the device antennas. Since transferring system frequency from the frequency of the antenna resonance strongly decreases power transfer efficiency, in this paper, a wireless power transfer system consisting of two helix resonance antennas is analyzed through quasi-static approximation in a circuit model and among the scientific papers; few works have been done in this regard. The presented circuit model reveals the difference between the two possible driving methods in wireless power transfer systems via coupled resonances. It also shows that the presented quasi-static approximation of wire helix resonant frequency is in a good agreement with the experimental results. In addition, the equivalent circuit elements of the wireless power transfer system via strongly coupled resonances are presented and measured to improve the transferred power and the maximum quality factor.