Design Of Solar Cell LED Lighting System

As a new type of green renewable energy, solar energy has a lot of advantages, for example, big reserve, cheapness, clean and environment protection, etc. The use of solar energy has been receiving increasing attention. Light Emitting Diode (LED) has the advantages of high efficiency, energy saving, long life, environmental protection, etc. Based on the advantages of LED and solar cells, this article carry out the corresponding research which focuses on solar cells and white LED lighting systems.This paper 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. Focusing on the problem of enhancing the utilization of solar power generation, we introduce and evaluate serveral kinds maximum power point tracking technologys that have been reported, such as the voltage feedback method, power feedback method, disturbance observation, electrical conductivity increment method. We present a new method of "solar cell series-parallel switching power point tracking method", which can achieve the changes in output parameters through the series and parallel topology. This method can achieve "active" type power tracking by making the solar sells have different internal resistance, voltage output parameters when the illumination is constant. This paper presents a series-parallel switch which combines light pressure isolators and VMOS tube low on-resistance.We designed and implemented the solar LED lighting controller which uses the microcontroller MCS89C2051. The controller has three kinds of illumination modes to suit requirements of different places, including a light control, delay off, delay-low brightness. The controller also has a battery overcharge, over-discharge protection. We show the hardware circuits and software flow charts and decribe the principles of the hardware and software working. Through the actual test, the lighting controller is stable and reliable.