Wireless power transfer (WPT) has been attracting a lot of attention in recent years for its ability to greatly improve the convenience of our lives. Moreover, WPT for Electric Vehicles (EVs) has become an important key to the spread of EVs. The efficiency of WPT using magnetic field resonant coupling can be evaluated by the kQ product, but the optimal coil design method to maximize the kQ product at a specific frequency has not yet been established. In this paper, taking the Test station GA-WPT1 and the Test station VA-WPT1/Z3 of SAE J2954, which is officially defined as the standard for WPT while the electric vehicle is stationary in October 2020, as examples, the coil parameters that maximize the kQ product in the case of the coreless are determined according to the proposed method. An efficiency of 99.13% was obtained with a transmission distance of 200 mm and the number of turns of N₁ = 34 and N₂ = 30. Also, since all analyses can be derived immediately except for the analysis of the Litz wire to be used, the optimization time could be reduced significantly compared with the electromagnetic field analysis. © 2022 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC.

中文翻译：

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基于数值分析的 85 kHz 频段电动汽车静态无线电力传输无芯线圈效率优化方法

近年来，无线电力传输 (WPT) 因其能够极大地提高我们生活便利性的能力而备受关注。此外，电动汽车（EV）的WPT已成为电动汽车普及的重要关键。使用磁场谐振耦合的 WPT 的效率可以通过kQ乘积来评估，但尚未建立在特定频率下最大化kQ乘积的最佳线圈设计方法。本文以 2020 年 10 月电动汽车静止时 WPT 标准 SAE J2954 的测试站 GA-WPT1 和测试站 VA-WPT1/Z3 为例，最大化kQ无芯情况下的产品根据建议的方法确定。在传输距离为 200 mm、匝数为N ₁  = 34 和N ₂  = 30 的情况下，获得了 99.13% 的效率。此外，因为除了要使用的利兹线的分析之外，所有分析都可以立即得出，与电磁场分析相比，优化时间可以显着减少。© 2022 日本电气工程师学会。由 Wiley Periodicals LLC 出版。