大功率LED路灯散热器的研究与优化

发布时间：2018-05-30 17:57

本文选题：大功率LED灯 + 有限元热分析　；参考：《广东工业大学》2014年硕士论文

【摘要】：大功率LED器件作为一种高转化率的绿色固态光源是目前最具有发展前景的新兴产业之一。LED路灯是高功率、高热流密度的电子器件,在长时间的工作中,面临着路灯中心温度积聚的问题。LED器件的发热问题导致路灯工作不稳定,照明的寿命和效率急剧下降。对LED路灯存在的热问题的研究显得十分必要。依据这一背景本文对路灯的发光原理,热力学参数和散热结构等关键问题进行探讨。研究采用有限元软件建立LED路灯模型并数值模拟其内部的热积累问题,对影响路灯最高温度和中心热量传递的因素进行分析。发现路灯散热器中的等距翅片结构,翅片间的疏密程度,散热器中心翅片的厚度和散热器底板的厚度对散热器的水平和垂直传热能力影响较大。为进一步研究这几个因素对路灯散热能力的影响,采用正交试验法在不同因素基础上设计出相应的正交表格,对应表格建立散热结构进行有限元数值模拟,得到最终优化结构。该优化方案解决了一般的LED路灯散热结构中心温度过高的问题,使结构的中心温度接近于结构的边缘温度,有效地降低了散热器的最高温度,同时加快了整体结构的散热速度和散热效率。所做的工作主要包括以下几个部分：首先,学习功率型LED路灯的基本结构和发热原理。包括LED基本结构和工作原理,LED灯的散热方式,LED温度的测量方法等；其次,研究功率型LED路灯的散热结构和散热技术。从散热原理、功率型LED衬底与封装技术、散热方式和温度测量方法四个方面分析了功率型LED的散热关键技术。然后,实验分析及熟练掌握ANSYS软件进行热模拟。分别将单个LED灯和路灯驱动工作,采用合适的温度测量方法,对单芯片和路灯工作到稳定状态的温度进行测量,采用有限元方法对单个LED灯和路灯进行数值模拟,最后将仿真结果与实验数据进行对比,验证仿真的可靠性。再次,针对要解决的问题,研究LED路灯散热器的设计方法。通过对高热流密度电子器件散热的经典方法和非等温肋片热特性进行研究与分析,得到影响LED路灯散热器性能的三个重要因素分别为散热器中心翅片的厚度、底板的厚度、不同疏密程度肋片结构。最后,对方案进行仿真实验。对应影响散热器散热的三个因素采用正交实验设计法列出正交表。采用ANSYS软件对LED路灯的温度进行数值模拟,得到仿真结果,并对仿真数据进行分析。从而得到对LED路灯温度进行有效热控制的优化组合。
[Abstract]:High power LED devices as a green solid-state light source with high conversion rate is one of the most promising emerging industries at present. Led street lamps are electronic devices with high power and high heat flux, which have been working for a long time. The heating of LED devices leads to unstable work of street lamps, and the life and efficiency of lighting decrease sharply. It is necessary to study the heat problem of LED street lamp. Based on this background, the luminescence principle, thermodynamic parameters and heat dissipation structure of street lamps are discussed in this paper. In this paper, the LED street lamp model is established with finite element software and the thermal accumulation problem is numerically simulated. The factors affecting the maximum temperature and central heat transfer of the street lamp are analyzed. It is found that the uniform fin structure, the density between the fins, the thickness of the central fin of the radiator and the thickness of the bottom plate of the radiator have great influence on the horizontal and vertical heat transfer ability of the radiator. In order to further study the influence of these factors on the heat dissipation ability of street lamps, the orthogonal test method was used to design the corresponding orthogonal tables on the basis of different factors. The corresponding tables were set up to build the heat dissipation structure and the finite element numerical simulation was carried out, and the final optimized structure was obtained. The optimization scheme solves the problem that the central temperature of the general LED street lamp heat dissipation structure is too high, and makes the center temperature of the structure close to the edge temperature of the structure, and effectively reduces the maximum temperature of the radiator. At the same time, it accelerates the heat dissipation speed and efficiency of the whole structure. The work done consists mainly of the following parts: First, learn the basic structure and heating principle of power LED street lamp. It includes the basic structure and working principle of LED lamp, the way of heat dissipation and the measuring method of LED temperature, etc. Secondly, the heat dissipation structure and heat dissipation technology of power type LED street lamps are studied. The heat dissipation key technology of power type LED is analyzed from four aspects: heat dissipation principle, power LED substrate and packaging technology, heat dissipation mode and temperature measurement method. Then, the experiment analysis and master ANSYS software for thermal simulation. A single LED lamp and a street lamp are driven to measure the temperature of a single chip and street lamp working to a stable state by using a suitable temperature measurement method. The numerical simulation of a single LED lamp and a street lamp is carried out by using the finite element method. Finally, the simulation results are compared with the experimental data to verify the reliability of the simulation. Thirdly, the design method of LED street lamp radiator is studied in view of the problem to be solved. Through the study and analysis of the classical method of heat dissipation of high heat flux electronic devices and the thermal characteristics of non-isothermal fins, three important factors affecting the performance of LED street lamp radiator are obtained, which are the thickness of the center fin of the radiator and the thickness of the bottom plate, respectively. Rib structure with different degree of density. Finally, the scheme is simulated. The orthogonal design method is used to list the orthogonal table for the three factors that affect the radiator heat dissipation. The temperature of LED street lamp is numerically simulated by ANSYS software, and the simulation results are obtained, and the simulation data are analyzed. Thus, the optimal combination of effective thermal control for LED street lamp temperature is obtained.
【学位授予单位】：广东工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM923.34

【引证文献】