Application of PV Powered High Intensity LEDs for Supplementary Irradiation of Horticultural Plants

摘要

The work presents a comprehensive study on problems of supplementary photosynthesis in horticultural plants realised by artificial light sources of optimised wavelength spectrum. A purely photovoltaic method of powering these sources is provided in order to avoid mains energy consumption. Three goals of the project are specified i.e. scientific, applique and usable ones. The first one deals with elaborating of algorithms for controlling, measuring and supplementing the photosynthesis process. The second - with laboratory engineering and equipment, while the third goal deals with utilization of elaborated methods and means for improving the quality and harvesting of the irradiated plants. Apart from the natural sunlight portions the entire supplementary photosynthesis bases on sun energy PV conversion to the red and blue light energy, additionally emitted by groups of red and blue LEDs, each of 1 to 3 W power. Their light intensity and mutual light proportions are controlled and optimised by a computer programme and by the electronic PWM and MPPT technique. Such an irradiation process, if necessary, may be carried on also in night hours or in cloudy periods by means of PV energy stored in batteries