volume | PIER Journals

Abstract

To explore the problem that the frequency characteristics of a magnetically coupled three-coil wireless power transfer (WPT) system are affected with different positions, in this paper, the expressions of the resonant frequency and the frequency corresponding to the maximum output power are deduced based on equivalent circuit theory. It is concluded that not only the resonant frequency is changed with different positions, but also the frequency corresponding to the maximum output power is changed with different positions. The WPT system always features a maximum efficiency point and a maximum output power point. The frequencies of the two points are almost the same. Finally, a three-coil experiment setup is built, and experimental results are well consistent with calculation and simulation results, which verifies the correctness of the proposed method. Proposed method provides a feasible scheme for simultaneously achieving high efficiency and high output power, and also provides a useful reference for the further research on the frequency tracking and optimization control algorithms.

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Dr. Xueyi Zhang

Dr. Yang Yuan

Dr. Zhongqi Li