This article proposes a novel method of improving the overall coupling coefficient of a wireless power transfer system by using a four‐winding transformer of which two pairs of windings each are connected in parallel in the primary side and secondary side. By weakening the coupling coefficients k_c between the parallel windings, the overall magnetic coupling between the primary side and secondary side of the transformer is improved. In order to confirm the validity of the proposed method, a conventional high‐k_c four‐winding transmission coil and the proposed low‐k_c four‐winding transmission coil are experimentally assessed. Then, the coils are introduced into a nonresonant inductive power transfer system utilizing a dual active bridge converter in order to confirm the correction of the input power factor. As a result, the overall magnetic coupling of the proposed four‐winding coils was found to be improved by 17% compared with the overall magnetic coupling of the conventional coil. Moreover, the input power factor for the entire load is corrected with the proposed four‐winding coil. Therefore, a low k_c is effective in improving the overall magnetic coupling.

中文翻译：

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具有多绕组传输线圈的无线电力传输系统的等效磁耦合系数的提高

本文提出了一种新颖的方法，该方法通过使用四绕组变压器来提高无线电力传输系统的整体耦合系数，该变压器的两对绕组分别在初级侧和次级侧并联连接。通过削弱并联绕组之间的耦合系数k _c，改善了变压器的初级侧和次级侧之间的整体磁耦合。为了确认所提出方法的有效性，采用了传统的高k _c四绕组传输线圈和所提出的低k _c对四绕组传输线圈进行了实验评估。然后，将线圈引入使用双有源桥式转换器的非谐振感应功率传输系统中，以确认输入功率因数的校正。结果，与常规线圈的整体磁耦合相比，建议的四绕组线圈的整体磁耦合提高了17％。此外，使用建议的四绕组线圈校正了整个负载的输入功率因数。因此，低的k _c在改善整体磁耦合方面是有效的。