Research About Cooling Structure Of High-power LED Lamps

With the advancement of Green Lighting Project, it has been the main task to seekhigh efficiency, energy saving and pollution-free light source in the lighting industry inrecent years. As the fourth generation of lighting source, LED has high brightness, lowconsumption, high reliability, long life and other advantages. More and more people useLED lamps with the growing demand for lighting. However, to grow the power of eachLED lamp become the main method to satisfy people’s need of the brightness of lampsand lanterns. Along with the power increasing, the junction temperature of LED rising,heat dissipation has been a bottleneck restricting the development of LED industry. So itis the effective way of extending the service life and promoting the development of LEDindustry to increase flux and reduce junction temperature. The main content of this paperis study the heat dissipation problem of high power LED lamps and lanterns, developeffective cooling devices through the contrastive analysis of the lamps and lanterns.First, the paper introduces the luminous principle and the development status at homeand abroad visually shows the prospects of the development of LED. The paperrespectively analysises the theory of thermal for the going study of heat dissipation,introduces the heat transfer mode, the cooling method of LED lamp and the simulation oftemperature field using the finite element softwareABAQUS. Preparing for the subsequentthermal resistance calculation, the paper analyzes the finite element theory of heat transferprocess, simulates the path of heat transfer of LED using thermal simulation.Secondly, on the basis of theoretical analysis, the paper introduces the trial-producesand simulations of three high power LED lamps and lanterns which are jointly developedby the project team and Constant light technology co., LTD. Jilin province. The specificprocesses are as follows: Debug the developed lamps and lanterns, measure temperature of various position with thermocouple at room temperature environment. Set up thetwo-dimensional simplified model of lamps and lanterns using AUTOCAD andthree-dimensional simplified model using UG or ABAQUS/CAE, import the models intoABAQUS and simulate the temperature field, we can get the temperature nephogram andtemperature gradient of lamps and lanterns. The radiator with fins is effective coolingdevice throught computing fin efficiency and thermal resistance of lamps and lanterns. Thefin efficiency is inversely proportional to fin height when other things being equal.Thermal resistance of binding materials account for a large proportion of thermalresistance of lamps and lanterns. It’s an effective way of reducing the thermal resistanceand speeding up the cooling to seek binding materials of high thermal conductivity.Thirdly, in view of the forming technology of the fin radiator, the paper introduces themanufacturing methods of fin, the manufacturing process of extrusion which is commonlyused in current production, the discussed aspects are extrusion equipment, the design ofextrusion mould and extrusion speed.Fourthly, on the base of respectively analysis between lamps with fins and lamps withwater-cooling, the paper compared the three lamps and lanterns and we can draw theconclusion: The lamp2with water-cooling is the most effective cooling device, waterplays a key role in the cooling systerm.Finally, on the basis of temperature testing and simulation, the paper contrasted theHigh-power LED lamps of fins and water-cooling in cooling mode, heat path, heatdissipation effect and so on, summarized the experimental conclusions, and pointed outthat need to be improved in the process of experiment and simulation, and the direction offurther research about heat dissipation problems of high power LED lamps and lanterns.