Design Of High Power LED Driving And Intelligent Control System

The technology of LED(Light Emitting Diode) had been developing since it was invented in 1960s and white light LED was successfully developed in 1990s. Because of the advantages of power saving, environmental friendly and long life, LED is hopeful to become new generation lighting source and it has already been widely used in various fields, especially in public illumination system such as street lamp, tunnel lamp.In this thesis we analyzed the working behaviors of LED, then we discussed the driving methods of LED. The driving methods of LED included AC driving and DC driving. At first we analyzed the feasibility of AC driving, then we designed a AC driving LED desk lamp, tested it and summarized both advantages and defects of AC driving. And then we discussed the working theories of switching power supply in DC driving. On the basis of fly-back converter, we used high precision operational amplifier to accurately regulate the output current and added ATmega8 SCM to design dimming system.With the design of dimming power supply and ATmega8 SCM system, we extended the software and hardware functions in system so as to design high power LED intelligent control system. In hardware we added temperature sensor, memory and RS485 interface circuit. In software we compiled RS485 communication protocols and designed intelligent control system software so that the whole system can implement temperature measuring, fault detecting, automatically dimming, and remotely dimming.The debugging and performing results show that the high power LED intelligent control system designed in this paper can accomplish temperature measuring, fault detecting, automatically dimming, remotely dimming accurately and operating stably and reliably. Therefore, the system has achieved the design target and fits the LED street lamp and tunnel lamp illumination system.