Research On The Properties Of High-power White LED Light Source System

With the development of science and technology, a new generation of green LEDs lighting has replaced the traditional lighting due to its high efficiency and environmental friendly properties. However, for practical applications, the development of LEDs also meets many challenges.The study is focusing on the relationship between the LED current and light color parameters of traditional packaged LEDs, SMD LEDs and flat packaged LEDs. The results show that with the increase of the forward current, the flux and correlated color temperature are increased, but the luminous efficiency is reduced gradually.For the heat dissipation problem, the attenuation of LEDs'luminous efficiency has been studied by a long aging experiment with three different packaging white LEDs. The results show that the flat packaged LEDs are the most effective way for heat dissipation. This package can decrease the attenuation of LEDs, so the life of LEDs has been extended. Then the research is focusing on the changes of the connected color temperature of SMD LEDs and flat packaging LEDs, which possesses smaller attenuation performance. With increasing the time, the correlated temperature of SMD LEDs is increased, whilst that of the flat packaging LEDs decreased.Because of the high performance requirement for LEDs circuit driver, the effects to LEDs of different circuit drivers are compared, the switching power supply has more efficiency performance than other power supply. In addition, the smaller and more efficient switching power supply is made by optimization of the inductor.