基于热电分离式理念的LED车灯光源的开发

Development of LED Automobile Lamp Based on Thermoelectric Separation Concept

基于热电分离式理念开发出一种功率为25 W且散热性能极佳的汽车灯照明用LED车灯光源,同时利用积分球系统和结温测试仪对其光热特性进行了表征,并利用快速温度变化实验箱通过冷热循环试验对其可靠性进行了验证,最后与目前应用较为广泛的卤素灯进行了对比研究。结果表明,当环境温度为30℃时,LED车灯光源的结温为118. 59℃;与卤素灯相比,LED在能耗仅为卤素灯46. 84%的前提下,其光通量、光功率、光效分别是卤素灯的2. 6倍、1. 34倍、5. 56倍;当环境温度为65℃,LED车灯光源工作6 000 h之后,光通量几乎无衰减;当循环初始温度为20℃时,光源经-40～85℃冷热循环100 cycle后仍然保持正常工作状态,完全满足实际工程应用要求。

An 25 W LED automobile lamp of excellent heat dissipation performance was developed on the base of thermoelectric separation concept. Integrating sphere system and junction temperature tester were employed to characterize its optical and thermal properties. Its reliability was confirmed through thermal cycle test using thermal cycling chamber and a comparison study was carried out between the LED lamp and the most widely-used halogen lamp in present. It was tound that the junction temperature of the LED lamp is 118.59℃ when the ambient temperature is 30℃. Even under the condition when the power consumption is merely 46.84% of that of halogen lamp, LED＇ s luminous flux, radiant power and luminous efficacy are 2.6 times, 1.34 times and 5.56 times that of the halogen lamp; when the ambient temperature is 65℃, the light failure of LED automobile lamp is almost zero alter working 6 000 hours; when the starting temperature is 20℃, LED automobile lamp is still working properly when experiencing 100 cycles with temperature varying from - 40℃ to 85℃, which totally satisfies the practical engineering application requirement.