Compared with traditional wired power transmission, wireless power transfer(WPT) has fully exhibited its key advantages of better safety and convenience, stronger reliability and electrical isolation, and less maintenance. Although the phase-shift modulation strategy has been widely used in various WPT applications, it has certain limitations in terms of high-frequency hard-switching, which increases the power loss of the WPT system during voltage regulation. To achieve efficient operation over a wide range of load power, this paper proposes a dual-frequency modulation strategy for the WPT system. The advantages of the dual-frequency modulation strategy are the simple modulation logic and the lower switching loss. It maintains the optimal load impedance during constant voltage output and improves the overall efficiency of the system. For validation, we designed the control circuit and wrote the control program and built the experimental prototype of the WPT system to carry out the phase-shift modulation experiment and the dual-frequency modulation experiment, respectively. The experimental results show that the soft switching range and efficiency of the WPT system under the dual-frequency modulation strategy are better. At the rated output power, the efficiency of the WPT system under dual-frequency modulation strategy is 89.75%. The feasibility of the dual-frequency modulation strategy has been confirmed.

中文翻译：

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无线电力传输系统双频调制策略研究

与传统的有线电力传输相比，无线电力传输（WPT）充分展现了其更安全便捷、可靠性和电气隔离更强、维护更少的关键优势。虽然相移调制策略已经广泛应用于各种WPT应用中，但在高频硬开关方面存在一定的局限性，增加了WPT系统在稳压过程中的功率损耗。为了在宽负载功率范围内实现高效运行，本文提出了 WPT 系统的双频调制策略。双频调制策略的优点是调制逻辑简单，开关损耗较低。它在恒压输出期间保持最佳负载阻抗，提高系统的整体效率。为了验证，我们设计了控制电路并编写了控制程序，搭建了WPT系统实验样机，分别进行相移调制实验和双频调制实验。实验结果表明，双频调制策略下WPT系统的软开关范围和效率更好。在额定输出功率下，双频调制策略下的WPT系统效率为89.75 实验结果表明，双频调制策略下WPT系统的软开关范围和效率更好。在额定输出功率下，双频调制策略下的WPT系统效率为89.75 实验结果表明，双频调制策略下WPT系统的软开关范围和效率更好。在额定输出功率下，双频调制策略下的WPT系统效率为89.75%。双频调制策略的可行性得到了证实。