The effect of heat dissipation of energy-saving high bay lamps and several suggestions
The life of energy-saving high bay lights largely depends on the level of heat dissipation, and the main way to improve the level of heat dissipation is to transfer the excess heat generated by the chip through the heat sink and heat sink. At the same time, the main parameters related to LED heat dissipation are thermal resistance and junction temperature. Temperature rise and so on.
Thermal resistance refers to the quotient obtained by dividing the difference between the effective temperature of the device and the external specified reference point temperature by the steady-state power dissipation in the device. It is the most important parameter indicating the degree of heat dissipation of the device.
The junction temperature refers to the temperature of the semiconductor junction of the main heat-generating part in the LED device. It reflects the temperature value that the LED device can withstand under working conditions. The heat resistance of the chip and phosphor is very high, and basically will not affect the life of the device.
The temperature rise refers to the temperature rise of the shell and the environment. It refers to the difference between the temperature of the LED device case and the ambient temperature. It is a temperature value that can be directly measured, and it can directly reflect the degree of heat dissipation around the LED device. If the temperature rises too high, the maintenance rate of the LED light source will be greatly reduced.
At present, the total heat dissipation efficiency of energy-saving high bay lamps is only 50%, and there is still a lot of electric energy to be turned into heat. Secondly, energy-saving industrial and mining lamps will generate more concentrated waste heat, which requires good heat dissipation. In order to improve the heat dissipation level, we provide the following suggestions:
1) From the perspective of LED chips, new structures and new processes must be adopted to improve the heat resistance of the junction temperature of the LED chip and the heat resistance of other materials, so that the requirements for heat dissipation conditions are reduced.
2) Reduce the thermal resistance of the LED device, adopt new packaging structures and new processes, and select new materials with better thermal conductivity and heat resistance, including bonding materials between metals, so that the thermal resistance is ≤10°C/W or lower .
3) Reduce the temperature rise and try to use heat dissipation materials with good thermal conductivity. The design requires better ventilation channels to dissipate the residual heat as soon as possible. The temperature rise should be less than 30°C.
4) There are many ways to dissipate heat, such as the use of heat pipes, of course it is good, but the cost factor should be considered, and the cost-effectiveness should be considered in the design.
In addition, the design of energy-saving high bay lamps should not only improve the efficiency of the lamp, the light distribution requirements, and the beautiful appearance, but also improve the heat dissipation level. Use materials with good heat conduction and coat some nanomaterials on the heat sink to increase the heat conduction performance by 30%. In addition, it must have better mechanical properties and tightness, and the heat sink must be dust-proof, and the temperature rise of the LED lamp should be less than 30°C.
