Laser-based wireless power transmission (LWPT) systems are one of the most promising systems in the long-range wireless power transfer field. However, few studies have focused on the efficiency characteristics of LWPT systems. Therefore, most LWPT systems are open-loop systems, making it difficult to best utilise their lasers and photovoltaic cells, thus preventing the system efficiency from being further improved. In this study, a closed-loop power control method is proposed for LWPT systems to explore the best performance conditions for such systems. To this end, the efficiency characteristics of a system are investigated by means of theoretical analysis and experimental measurements. The results show that the duty cycle of the laser input current is one of the key factors for improving the system efficiency. Then, a dual closed-loop controller, which includes an optimal duty cycle search algorithm, is proposed based on the obtained system characteristics. Finally, a small-scale prototype is fabricated and tested in the laboratory to verify the effectiveness of the proposed power control method.

中文翻译：

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用于提高基于激光的无线电力传输系统的效率的功率控制方法

基于激光的无线电力传输（LWPT）系统是远程无线电力传输领域中最有前途的系统之一。但是，很少有研究集中在LWPT系统的效率特性上。因此，大多数LWPT系统是开环系统，因此很难最好地利用其激光器和光伏电池，从而导致系统效率无法进一步提高。在这项研究中，为LWPT系统提出了一种闭环功率控制方法，以探索此类系统的最佳性能条件。为此，通过理论分析和实验测量来研究系统的效率特性。结果表明，激光输入电流的占空比是提高系统效率的关键因素之一。然后，一个双闭环控制器，基于所获得的系统特性，提出了一种包含最优占空比搜索算法的算法。最后，制造了一个小型原型并在实验室中进行了测试，以验证所提出的功率控制方法的有效性。