volume | PIER Journals

Abstract

The focus of this study is the design of a multi-transmitter single-receiver wireless power transfer (MTSR-WPT) system, particularly for implantable medical devices such as brain pacemakers. Conventional charging methods rely on invasive surgery or frequent battery replacement, posing significant challenges for patients. To address this issue, this work proposes an MTSR-WPT system based on a flexible printed circuit board (FPCB). The designed small-coil array topology leverages the mechanical flexibility of FPCB to conform to complex biological surfaces, significantly enhancing two-dimensional omnidirectional anti-misalignment capability while reducing magnetic leakage during operation. To further compensate for misalignment between the transmitter and receiver, a backpropagation neural network optimized by the Seagull Optimization Algorithm (SOA-BP) is introduced for receiver coil position prediction, combined with a fuzzy PID control strategy for dynamic output voltage regulation. Simulation and experimental results demonstrate that under a fixed load condition, the proposed system achieves stable energy transfer within a 120 mm charging area, maintaining an output power exceeding 1 W when the receiver coil is positioned at a height of 20 mm. Compared with traditional single-coil systems, the optimized multi-coil array exhibits superior performance in both misalignment tolerance and magnetic leakage suppression. These results verify the effectiveness of the proposed MTSR-WPT system and highlight its potential for implantable medical devices and other power electronic applications, providing a novel solution for achieving efficient and reliable wireless energy transfer.

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Dr. You Fu

Mr. Jianan Luo

Mr. Xinguang Chen

Dr. Dequan Jiang