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.