激光供能无人机光伏接收器效率优化方法

激光供能无人机(LPUAV)通过激光无线能量传输进行实时能量补给,大幅提升无人机续航时间。但激光束能量分布不均匀,导致光伏接收器效率低下。通过推导串并联光伏组件在不均匀光照条件下的输出方程,针对I-V、P-V曲线、光伏电池效率及组件整体效率进行对比研究,着重分析了串并联组件效率与光照不均匀度的关系及内在机理。研究表明,并联旁路二极管的串联组件在不均匀光照下存在多峰现象,且光伏电池易受影响而偏离最大功率点,导致组件整体效率降低,而并联组件受不均匀光照影响较小,但组件电压较低。其次搭建激光无线能量传输的实验装置,进行了不均匀激光辐照下激光无线能量传输的初步研究,并对比了串并联组件的输出特性。研究结果验证了通过优化电路连接方式以提高光伏接收器效率的可行性。

Methods to improve efficiency of photovoltaic receiver for laser powered unmanned aerial vehicle

Endurance time of laser powered unmanned aerial vehicle(LPUAV)is prolonged significantly for energy supply. But non-uniform laser spot leads to serious power loss of photovoltaic receiver. Output characteristic models of series and parallel photovoltaic module were derived firstly. Based on the models, output characteristics of photovoltaic module, e.g. I-V and P-V curves, efficiency of photovoltaic cells and module, were analyzed. The relationship between efficiency and non-uniformity of illumination was also studied. The result indicates photovoltaic cell diverges from its maximum power point which leads to efficiency drop of series photovoltaic module. On the contrary, parallel connection with low voltage is less influenced by non-uniform illumination. An experiment was also conducted to study laser wireless power transmission. Output characteristics of series and parallel photovoltaic module were measured and analyzed correspondingly. The feasibility of improving efficiency of photovoltaic receiver by designing a suitable circuitry connection is proved.