In the inductive wireless power transmission (WPT) designs of consumer electronics and implantable devices, the printed planar coil in standard manufacture is commonly used. Layout optimization of the coils is one of the important ways to make the power transmission system more efficient. Varying the trace width and turn-to-turn spacing together for the coils is proposed to optimize the maximum achievable power transfer efficiency (𝜂max). An accurate analytical model for the printed square coils is also established as well to speed up the design process. By virtue of this model, an optimal scaling factor of the trace width and the optimal frequency can be quickly estimated. The proposed model is validated by both the simulations (ANSYS HFSS) and experiments. A WPT link of two planar coils with size of 50 mm × 50 mm × 1 mm, operating at 23 MHz, is optimized by using this methodology. After optimization, the measured 𝜂max of the WPT system is increased from 22.60% to 32.74% at a 100-mm transmission distance.

中文翻译：

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用于感应无线电力传输的具有可变走线宽度的印刷平面线圈的分析布局优化

在消费电子和可植入设备的感应式无线电力传输 (WPT) 设计中，通常使用标准制造中的印刷平面线圈。线圈的布局优化是提高电力传输系统效率的重要途径之一。建议同时改变线圈的走线宽度和匝间间距，以优化可实现的最大功率传输效率 (𝜂max)。还建立了印刷方形线圈的准确分析模型，以加快设计过程。借助该模型，可以快速估计走线宽度和最佳频率的最佳比例因子。所提出的模型通过仿真 (ANSYS HFSS) 和实验进行了验证。两个平面线圈的 WPT 链路，尺寸为 50 mm × 50 mm × 1 mm，工作频率为 23 MHz，使用这种方法进行优化。优化后，WPT 系统测得的 𝜂max 在 100 毫米传输距离下从 22.60% 增加到 32.74%。