Misalignment is a problem faced when electric vehicles work under the dynamic wireless charging mode using segmented transmitting coils. One kind of coil misalignment is coil lateral offset. In order to improve lateral offset tolerance, transfer efficiency and output power need to be stabilized. In this paper, first, the circuit model of a wireless power transfer (WPT) system is analyzed, from which mutual inductance is the major factor of the transfer efficiency decline caused by coils' lateral offset. The mutual inductance of two parallel square coils with lateral offset is analyzed. With the length and width of the transmitting coil being optimally designed according to the mutual inductance analysis, the mutual inductance of coils with lateral offset is optimized, and thus, transfer efficiency can be stabilized, and the system lateral offset tolerance is preliminarily improved. Moreover, in order to further enhance the lateral offset tolerance, the secondary‐only resonant series–series (S–S) topology is adopted to stabilize the system output power. Finally, the optimal design with stabilized transfer efficiency is verified by the finite element simulation and the experiment with coils being scaled down. Due to the limitation of experimental conditions, the stability of output power is verified by simulation. © 2020 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

中文翻译：

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电动汽车动态无线充电横向偏移公差的优化研究

当电动汽车使用分段发射线圈在动态无线充电模式下工作时，未对准是一个问题。线圈未对准的一种是线圈横向偏移。为了改善横向偏移公差，需要使传输效率和输出功率稳定。在本文中，首先，分析了无线电力传输（WPT）系统的电路模型，互感是导致线圈横向偏移导致传输效率下降的主要因素。分析了两个具有横向偏移的平行方形线圈的互感。根据互感分析优化设计发送线圈的长度和宽度，优化了横向偏移的线圈的互感，从而可以稳定传输效率，初步改善了系统的横向偏移公差。此外，为了进一步提高横向偏移容差，采用了仅次级谐振串联（SS）拓扑来稳定系统输出功率。最后，通过有限元模拟和按比例缩小线圈的实验，验证了具有稳定传输效率的最优设计。由于实验条件的限制，通过仿真验证了输出功率的稳定性。©2020日本电气工程师学会。由Wiley Periodicals LLC发布。通过有限元模拟和按比例缩小线圈的实验，验证了具有稳定传输效率的最佳设计。由于实验条件的限制，通过仿真验证了输出功率的稳定性。©2020日本电气工程师学会。由Wiley Periodicals LLC发布。通过有限元模拟和按比例缩小线圈的实验，验证了具有稳定传输效率的最佳设计。由于实验条件的限制，通过仿真验证了输出功率的稳定性。©2020日本电气工程师学会。由Wiley Periodicals LLC发布。