Design And Implementation Of Thermal Management System For High-power LED

LED is the abbreviation of light-emitting diode,which is a new type of low-carbon and energy-saving light source.Compared with traditional incandescent lamps,LEDs consume less power and are more environmentally friendly.Therefore,LEDs are widely used in various lighting projects such as household lighting,road lighting,and landscape lighting,and have become the mainstream light source for lighting projects.As the integration of LED chips increases,the heat generated by them also increases sharply.However,the excessively high junction temperature will inevitably affect the life of the LED lamp.Therefore,the heat dissipation design of the LED heat source is very critical.Based on the thermal system structure of high-power LED devices,this paper proposes a sisal-like runner cold plate.At a normal temperature of 25°C,the coolant flows around the cold plate quickly after passing water through the middle interface of the cold plate,quickly taking away heat,so that the maximum junction temperature of the 150 W highpower LED does not exceed 65°C.At the same time,a host computer interface display software was developed for real-time monitoring of high-power LED working conditions,and a miniaturized LED thermal management system was designed.It has reference significance and certain market application value for the heat dissipation design of highpower electronic equipment.The specific work content of this paper is as follows:(1)Based on the theory of heat transfer,fluid mechanics and the thermal system structure of LED devices,a cold plate with imitated sisal-shaped runner structure is proposed.The cold plate structure draws lessons from the excellent mass and heat transfer characteristics of some plants in nature.By comparing the heat dissipation effects of cold plates with three structures,i.e.,sisal-shaped runner,cobweb-shaped runner,and square flow channel,it is found that the sisal-shaped structure has the best temperature uniformity,minimum pressure drop and better cooling effect.(2)Study on the thermal simulation boundary conditions of the sisal-like runner and the optimization of the cold plate structure.In terms of boundary condition optimization,the fluid working fluid and cold plate material are optimized respectively,and the boundary condition parameters such as inlet temperature,inlet flow rate and heat flux density are changed,and the thermal simulation analysis of the imitation sisal-shaped cold plate is carried out.In terms of the optimization of cold plate structure,optimization research is carried out for the export quantity and import and export direction.Build an LED liquid cooling experiment platform,compare the experimental data with the simulation data,and perform error analysis.(3)Designed a collection circuit based on multiple sensors.Compared with the traditional temperature control circuit that only collects the temperature of the heat source to change the fan speed to realize heat dissipation,this circuit not only collects the temperature of the heat source,but also collects the inlet and outlet temperature,inlet and outlet pressure,flow rate and liquid level of the cold plate,which is LED liquid cooling.The system provides more data references.(4)Develop a miniaturized and intelligent LED thermal management system.The system displays the data collected by all sensors in real time,which is convenient for users to understand LED working conditions and conduct human-computer interaction.The overall size of the system is small,but the heat dissipation efficiency has not been reduced.The system also has an audible and visual alarm function.When the LED has an emergency that the temperature is too high,the user can be notified in time.In addition,a segmented control mode that can adjust the speed of the water pump and fan can effectively reduce the LED temperature to a stable state.Finally,the LED thermal management system was tested,and the test results verified the stability and safety of the system.