volume | PIER Journals

Abstract

Eddy current effects in underwater wireless power transfer (UWPT) systems introduced additional losses and shifted circuit parameters, severely undermining precision of conventional primary-side identification. To address this issue, this study investigated the mechanism of eddy current loss and established an improved mutual inductance model by introducing an equivalent eddy current resistance. Based on this, a primary-side sensing identification method was proposed to achieve the decoupled identification of mutual inductance, load resistance, and eddy current resistance by measuring the input impedance Z_in at multiple frequencies. Experimental results confirmed that at a resonant frequency of 85 kHz, the identification errors for eddy current resistance, mutual inductance, and load resistance were within 4%, 3%, and 5%, respectively. Furthermore, the average error remained below 3.5% across various salinities, lateral misalignments, and load conditions. This study provided a reliable technical foundation for optimizing the performance and ensuring stable operation of UWPT systems in complex underwater environments.

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Dr. Zhongjiu Zheng

Prof. Zhuang Li

Dr. Anran Liu

Dr. Hanxi Xu

Dr. Minghao Zhao