The Research And Design Of Solar Led Lighting System

In the 21st century,with the intensification of the world energy crisis,solar energy is considered as the most common and clean energy. It is focused on by human with its advantages as below:bringing little pollution to the air,hardly destroying the ecology,causing no"greenhouse effect".At the same time,LED has the advantages of high efficiency,energy saving,long life,environmental protection, has already been widely used in various lighting situations as an ewgeneration of the green Lighting source.This paper studies photovoltaic power generation system management control chip design problems, describes the research background,dynamics and development trends of photovoltaic lighting systems in domestic and oversea,and also describes the basic knowledges of the solar cells,batteries,white LED. The solar cells have different maximum Power Point(MPP) at different temperature and irradiation. In order to inerease the utilization rate of solar array, maximum Power Point traeking(MPPT) methods can be used to maximize its power output. We introduce and evaluate serveral kinds of maximum power point tracking technologys that have been reported,such as the voltage feedback method, electrical conductivity increment method, disturbance observation. We present a new method of "A variable step disturbance observation".Use photoconductive resistance in the illumination when resistance change principle, so as to realize the automatic tracking the solar energy function by motor drive. The charging and discharging control of battery affects its operating life. On the base of the research on the working characteristics of battery and analysis of different charge methods, a new three stages battery-charging method which is based on UC3906 and pulse charging method is putted forward in this thesis.A Bi-directional boost converter is proposed to realize maximum power point tracking and LED driver.We designed and implemented the solar LED lighting controller which uses the microcontroller HT46R47,monitored the solar system,storage battery charging and dischanging and led light. We show the hardware circuits and software flow charts, Through the actual used,the lighting controller is stable and reliable.