Research Of Pulse Power Driving High Power LED

Semiconductor lighting is globally acknowledged to be a new generation of environment-friendly high-tech new light source, known as another revolution with true sense after the invention of the electric light by Edison.High-power LED(light-emitting diode) with high efficiency, energy saving, environmental protection, long lifespan, high reliability advantages is gradually replacing traditional incandescent lamp and fluorescent lamp as a new generation of light source. However, for the overall life of LED lighting apparatus and luminous efficiency ,optoelectronic integrated applications must be taken into account.Therefore, LED driving power plays a vital role for the expression of LED energy efficient performance.Based on the Pulse-Width Modulation circuit (PWM) principle, this paper researchs on the technology which shows how DC pulse drives high-power LED. Through the measurements of the actual power consumption when LED drived by pulse with different duty cycle ,we found with the same power consumption, the voltage differences between pulse-driven approach to maintain the peak current unchanged and the steady-state DC-driven approach,and reveals the main reason for the declining luminous efficiency of Pulse-driven; when the environmental temperature changes can be ignored ,through monitoring LED device temperature and the test of PN junction temperature ,found the temperature of LED devices and the PN junction is proportionally changed with the average power; Through the measurement of transient light intensity when drived by pulse, found that with the duty cycle reduced peak flux continuously improve, mainly because the decrease of LED driver power leads to PN junction temperature dropping,and brings efficiency increase of PN junction electro-optical conversion;in the study of the changes of LED color temperature in the pulse-driven, found that the major factor of changes in color temperature parameter is temperature (LED of the PN junction temperature) and the electric field strength (drive-current amplitude),the use of pulse-driven approach is the best option to regulate LED brightness and maintain color temperature unchanged.In addition, on the basis of the existing instruments this paper observed the difference between steady-state DC LED driver and pulse transient driver, tried to change the optimization of experimental methods and meaned to assist the task force initially establish a set of parameters for LED transient test methods . Its components, including high-power pulsed power, transient data acquisiting and processing systems. Based on this system, this paper made an in-depth research on the pulse of the LED drive, analysised the assessments on the emerging market for LED pulse driver, for more effectivly using LED and choosing a suitable driver, in particular the the appling conditions of pulse-driven programmes as an useful study.