Research And Design Of Intelligent Solar LED Lights

Solar energy generation is a way to develop renewable energy, LEDlighting is a primary pattern in future lighting. Solar energy LED streetlightcombines solar energy generation with LED lighting, it not only can implementsaving energy and reducing emission, but also provide a low-cost way toillumination in remote area where no power grids. So research and design solarLED streetlight is necessary and meaningful.The main point of the thesis is to design an intelligent charging anddischarging controller which includes MPPT charging part and constant-currentdriver with LED loads. Through fully analyzing the characteristic of solar cell,lead-acid battery and LED, we design a modified three stage charging mode forlead-acid battery based on Buck converter, which combines MPPT, constantvoltage and constant current charging mode in itself. Also, we design aconstant-current driver with LED loads based on Boost topology, andimplement a progressive PWM way to dim the LED loads and an intelligentway to distribute the lighting power according to the brightness on streetperiodically.This paper presents the hardware design procedure of the solar energy LEDstreetlight system based on dsPIC33FJ16GS502and accomplishes the relevantprogram using C language, the expectant control functions during the chargingand discharging process has been realized. It is showed that the designed systemin this paper has achieved well performance as expected by analyzing theexperimental data and waveforms.