Analysis and Experiment of the Laser Wireless Energy Transmission Efficiency Based on the Receiver of Powersphere

Long-distance wireless energy transmission is realized by photoelectric conversion through lasers and photovoltaic cells. However, existing devices have low transmission power and low transmission efficiency. Exploring the main factors that limit the transmission efficiency during transmission is necessary to improve the transmission power and efficiency, and theoretically analyze these factors that affect transmission efficiency, such as beam quality, divergence angle, wavelength and so on. This will provide research directions for subsequent work. A multiwavelength laser wireless energy transmission experimental platform was built by using powersphere, laser with three different wavelengths and other devices. This platform was used for transmission efficiency verification experiment. The total electro-optical-electric conversion efficiency values obtained by the 532, 1030, and 808 nm lasers are 0.01%, 0.08%, and 0.11%, respectively. The corresponding laser-to-electric conversion efficiency values are 1.37%, 1.60%, and 0.73%, respectively. Experimental results show that the electro-optic conversion efficiency of the laser and the photoelectric conversion efficiency of the photovoltaic receiver is the main reasons for the low conversion efficiency of the system. In addition, factors such as the expansion ratio of the beam expander, laser collimation, laser uniformity at the photovoltaic receiver end, and circuit structure, affect the conversion efficiency of the system.