POWER LED Heat Dissipation Research Based On IWC SYSTEM

In recent years,energy conservation and environmental protection have become the goals pursued by the manufacturing industry.As the ―green light source‖ of the new era,LEDs are widely used in the field of lighting because they consume relatively low power and generate high luminous flux.The birth of the power type LED is in line with many of the requirements of the use of light sources.However,due to the LED’s own structure and lighting principle,the heat generated by the LED in the working process is difficult to disperse through radiation.As a result,the junction temperature of the LED chip is higher than the normal range,which seriously affects the lighting performance and the service life of the LED.This is the most important factor restricting the development of LED.Therefore,it is particularly important to design an efficient thermal management scheme to greatly reduce the junction temperature of the LED chip.In this study,based on the inherent defects of traditional heat dissipation schemes,an IWC(Ionic wind cooling)heat dissipation system based on electrohydrodynamics was designed,and an IWC heat dissipation test system was set up to explore the EHD,volt-ampere characteristics,and structural optimization of IWC systems.The system laid the foundation for the heat dissipation of LED chips.Through comparative experiments,the effects of power polarity,tip radius of curvature,and emitter electrode structure on the cooling effect of the device were studied,thereby optimizing the IWC heat dissipation system and obtaining a set of optimal thermal management solutions.In addition,the heat sink is applied to high-power LED chips.The input power control strategy is studied and the best control method is obtained.At the same time,the luminous flux of the LED,the thermal resistance of the heat dissipation system,and the average heat transfer coefficient were measured,confirming the feasibility of IWC refrigeration.The research shows:The IWC heat dissipation system can control the junction temperature of the LED chip to be below 50°C.At the same time,the ionic wind generation can greatly reduce the thermal resistance of the system,the luminous flux of the LED output,and increase the average heat transfer coefficient between the electrodes.When the radius of curvature of the needle tip and the discharge distance are small,negative corona discharge is used,and the “╋” needle electrode arrangement method can generate ionic wind at a lower corona voltage,and the cooling effect is the best.The heat dissipation system has a higher working stability,and the volt-ampere characteristic curve in the ion wind generation process meets the classical Townsend relationship.It was found that the maximum electric field strength value was obtained near the needle electrode.The ion wind speed increased rapidly with the dynamic pressure,and then the speed was slowed down.At the same time,the charge density of the corona discharge was proportional to the overvoltage,but inversely proportional to the square of the discharge gap.