This paper is to present the design, analysis and verification of a new hybrid wireless power transfer (HWPT) system, which has a space-saving coupler structure. The key of the design is to simplify two coupling capacitor plates into one single frame-shaped plate at each side. Then, the coupling coil for inductive power transfer (IPT) is embedded into the metal frame to form a compact hybrid coupler. Meanwhile, the coupling polarity between the coils is specified to realize the superposition of the inductive and capacitive coupling. As a result, the proposed HWPT system can offer a good comprise of efficiency promotion and a space-saving coupler structure simultaneously. To illustrate the system working principle, the equivalent circuit model is firstly derived. Then, a detailed analysis is conducted in terms of the reflected impedance. Consequently, the mechanism of the efficiency promotion can be clearly explained. Finally, a prototype is constructed with experiments, which validates the effectiveness of the proposed HWPT system. Results show that an efficiency increase of 14% over the pure IPT is obtained at 35 cm distance. Moreover, the effects of varying the resonant frequency are also carried out to instruct the practical system design.

中文翻译：

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一种具有节省空间耦合器结构的新型混合无线电力传输系统的设计与分析

本文将介绍一种新型混合无线电力传输 (HWPT) 系统的设计、分析和验证，该系统具有节省空间的耦合器结构。设计的关键是将两个耦合电容器板简化为每侧一个框架形板。然后，将用于感应功率传输 (IPT) 的耦合线圈嵌入金属框架中以形成紧凑的混合耦合器。同时，指定线圈间的耦合极性，实现感性和容性耦合的叠加。因此，所提出的 HWPT 系统可以同时提供效率提升和节省空间的耦合器结构的良好组合。为了说明系统的工作原理，首先推导出等效电路模型。然后，根据反射阻抗进行详细分析。因此，可以清楚地解释效率提升的机制。最后，通过实验构建了一个原型，验证了所提出的 HWPT 系统的有效性。结果表明，在 35 cm 距离处获得的效率比纯 IPT 提高了 14%。此外，还进行了改变谐振频率的影响，以指导实际的系统设计。