摘要:随着LED光效的不断提升,LED射灯技术也在迅速地发展。传统射灯多采用卤钨射灯,发光效率较低、比较耗电、使用寿命短。而LED光源在发光原理、节能、环保的层面上都具有较显著的优势,并且LED射灯的成本也在下降,所以其应用也广泛普及。但是LED射灯受其外形、灯头、和安装要求限制,使得很难在现有射灯的标准尺寸范围内将一个LED射灯做到高功率和高光通量。LED电光转化效率低,使LED射灯严重发热,而LED射灯散热设计不当,将导致LED芯片结温过高,器件寿命缩短,光效降低。所以,散热是LED灯具设计必须着重考虑的因素。
本课题为了探究影响LED射灯散热的因素,分别改变灯珠的个数、灯罩的有无和风扇的有无,设计了八个实验,利用热电偶记录仪进行温度测量,通过对实验数据的对比,得出了导热系数高的灯罩和加入风扇都能显著降低LED射灯灯珠温度的结论。接着对实际的四种灯具模型进行ProE建模,并通过热流软件FloEFD进行仿真,得到的模拟温度结果,与实验温度进行比较,最后验证了实验中加入高导热系数材料的灯罩可以增加导热面积有效降低芯片结温。34782 毕业论文关键词:LED射灯;散热;仿真
Analysis of LED spotlight heat dissipation experiment
Abstract:With the luminous efficiency of LED is increasing, LED technology has been developed rapidly. Traditional spotlights uses halogen tungsten spotlights which luminous efficiency is lower, more power consumption, short service life. And the LED light source on the level of luminous principle, energy-saving, environmental protection has more significant advantages, and the cost of the LED spotlights is declining, so its application is also widely used. But the LED spotlights restricted by its appearance, spotlights holder, and installation requirements, it is difficult to let LED achieve a high power and high flux within the scope of the standard size of existing spotlights.LED photoelectric conversion efficiency is low, the serious heating of LED spotlights, and LED spotlights radiating improper design will lead to the LED chip junction temperature is too high, the device life is shortened, light efficiency is reduced. So, the heat dissipation is the factor that must be considered in the design of LED spotlights.
This topic in order to explore the factor of influencing the LED spotlights dissipation,according to the change of the number of lamp bead and the presence of lamp-chimney and fan,I have designed eight experiments.And I have recorded the temperature using thermocouple recorder for temperature measurement . Then I have the conclusion that the lampshade of high thermal conductivity and fan can significantly reduce the temperature of the LED spotlight temperature by the comparison of experimental data.Then ProE model of four kinds of LED lanterns is carried out.And the simulation of the heat flux is carried out through the software FloEFD.The results of the simulated temperature which are obtained compared with the experimental data.In the end, the experimental results show that the high thermal conductivity of the material can increase the heat conduction area and reduce the temperature of the chip.
Keywords:LED spotlights;heat dissipation;simulation
目录
1引言 1
1.1 研究现状与发展趋势 1
1.1.1 LED射灯的特点 1
1.1.2 LED射灯散热方法 1
1.1.3 LED射灯散热的技术 2
1.1.4 本课题要解决的问题 2
1.2 主要研究内容 3
1.3 研究目的及意义 3
2LED射灯的热学分析 5
2.1 LED射灯的热学特性 5
2.1.1 LED芯片的结温 5
2.1.2 LED的热阻 5