volume | PIER Journals

Abstract

Wireless power transfer systems suffer from frequency splitting and drift due to horizontal coil offset, which degrade both efficiency and output power. This paper derives a sixth-order equation to calculate resonant frequencies at the maximum efficiency point (Freq-MEP). The frequencies at the maximum power point (Freq-MPP) are determined by differentiating the output power with respect to the operating frequency. Both Freq-MEP and Freq-MPP are shown to vary with horizontal offset. Based on this analysis, a segmented frequency-tracking method is proposed to achieve simultaneous high efficiency and high output power under varying offset conditions. The effectiveness of the developed magnetic resonant WPT system is validated through numerical simulations and experiments.

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Dr. Junjun Li

Dr. Jialin Zou

Dr. Yao Zou

Dr. Zhongqi Li