大功率集成芯片LED场地照明灯具散热研究

发布时间：2018-05-29 17:57

  本文选题：大功率LED + 热阻　； 参考：《重庆大学》2014年硕士论文

【摘要】：LED灯因其节能、环保、寿命长等特点被称为新一代绿色光源，但其发光效率低。随着LED功率不断增大，若不进行有效散热，LED的寿命及发光性能都受到影响甚至完全失效。开发新型成本低且具有良好散热性能的LED灯具，是大力推广新一代光源的关键。单颗LED芯片功率较小，在场地照明灯等领域为获得足够光通量必须封装多颗芯片，其散热问题更为突出。 论文通过实验与数值模拟相结合方法研究了自然对流条件下的多芯片LED散热情况。从芯片、封装、界面、系统方面，对多芯片铜基板COB封装直焊LED灯散热进行一些研究。在此基础上设计了一款大功率场地照明用LED灯，并分析了包括电源在内的整个灯具的散热性能。 芯片与封装方面，分析研究芯片间距、覆铜层厚度、喷涂铜层厚度对扩散热阻的影响；界面方面，将冷喷涂直焊与传统压接方式进行对比，分析冷喷涂直焊对整个灯具热阻减小的作用；系统级散热方面，主要针对自然对流这一被动散热方式，通过改进现有散热器，分析了散热器面积增加对整个灯具散热的重要性。 基于以上的分析和结论，提出了一款用以代替传统场地照明的LED灯具。该灯具利用冷喷涂直焊方法将250W铜基板多芯片集成封装模组与设计的纯铝叠片散热器相结合制造而成。其中，叠片式散热器用纯铝代替铝合金，减小了散热器热阻；同时，叠片散热器实现了低成本加工薄纯铝板，有效增加散热面积。通过分析，结合冷喷涂直焊技术该叠片散热器完全满足设计场地照明LED灯具的散热要求。即使在35℃环境和275W功率下，芯片结温也能控制在110℃以下。
[Abstract]:LED lamp is called the new generation green light source because of its energy saving, environmental protection, long life and so on, but its luminous efficiency is low. With the increasing of LED power, the lifetime and luminescence performance of LED without effective heat dissipation are affected or even completely invalidated. Developing a new type of LED lamps with low cost and good heat dissipation is the key to popularize the new generation of light sources. The power of a single LED chip is small. In order to obtain sufficient luminous flux, it is necessary to encapsulate multiple chips in the field of field lighting, so the heat dissipation problem is more prominent. In this paper, the heat dissipation of multi-chip LED under natural convection is studied by the combination of experiment and numerical simulation. From the aspects of chip, package, interface and system, the heat dissipation of LED lamp for COB packaging of multi-chip copper substrate is studied. On this basis, a LED lamp for high power field lighting is designed, and the heat dissipation performance of the whole lamp, including power supply, is analyzed. In chip and package, the influence of chip spacing, copper coating thickness and spray copper coating thickness on diffusion thermal resistance is analyzed. This paper analyzes the effect of cold spray direct welding on the decrease of thermal resistance of the whole lamp, and analyzes the importance of the increase of radiator area to the heat dissipation of the whole lamp by improving the existing radiator, aiming at the passive heat dissipation mode of natural convection. Based on the above analysis and conclusion, a new LED lamp is proposed to replace the traditional site lighting. This lamp is fabricated by cold spray direct welding method, which combines 250W copper substrate multi-chip integrated packaging module with the designed pure aluminum laminated radiator. The laminated radiator uses pure aluminum instead of aluminum alloy to reduce the thermal resistance of the radiator. At the same time the laminated radiator can process thin aluminum plate at low cost and increase the heat dissipation area effectively. Through analysis, the laminated radiator can fully meet the heat dissipation requirements of the design site lighting LED lamps combined with the cold spray direct welding technology. Even at 35 鈩，

本文编号：1951857