Research And Design Of Stand-alone Solar LED Illuminating System

Green energy and sustainable development are the major issues facing mankind in this century. With "green, energy-saving, environmental" as the theme, low-carbon economy will become an important theme in the future. As a clean and renewable energy, photovoltaic power developed quickly around the world. LED has already been widely used in various lighting situations as a new generation of the green lighting source. Solar LED Lighting System which combines the advantages of the new energy and the new illumination source has a huge developing space and will lead us to a green and energy-saving era.The solar array have different maximum power point (MPP) at different temperature and irradiation. In order to increase the utilization ratio of solar array, maximum power point tracking (MPPT) methods can be used to maximize its power output. In this thesis an adaptive perturbation and observation method is used to realize MPPT. The application of concentration and solar tracking technology in Solar LED Lighting System has also been discussed in this thesis.The charging and discharging control of battery affects its operating life significantly. On the base of the research on the working characteristics of battery and analysis of different charge methods, a new battery-charging method which is based on MPPT and pulse charging method is putted forward in this thesis.Scientific design of the LED driver will enhance LED lamp's lighting effect and extend LED lamp's service life. A new LED driver based on CUK convert has been designed on the base of analysis of the principle of LED-driving. A modularization Design of LED driver has also been introduced in this thesis.According to the characteristic of the whole system, the preliminary design of the controller for the illuminating system is presented in this paper, as well as its hardware and software.