What are the ways to improve the heat dissipation efficiency of LED explosion-proof lamps
Datetime: 2021-03-09 10:35:34
For high-power LED explosion-proof lights, heat dissipation has become a bottleneck restricting the development of LED explosion-proof lights. Semiconductor refrigeration technology has the advantages of small size, no need to add refrigerant, simple structure, no noise, stability and reliability. With the advancement of semiconductor material technology and the discovery of high-spot conversion materials, semiconductor refrigeration technology is used to solve LED explosion-proof The heat dissipation problem of the lamp lighting system will have very practical significance.
1. The cause of LED heat and the influence of heat on LED performance:
Under the forward voltage of the LED, electrons obtain energy from the power supply. Under the drive of the electric field, they overcome the electric field of the PN junction and transition from the N region to the P region. These electrons recombine with the holes in the P region. Since the free electrons drifting to the P zone have higher energy than the valence electrons in the P zone, the electrons return to a low-energy state during recombination, and the excess energy is released in the form of photons. However, only 30% to 40% of the released photons are converted into light energy, and the remaining 60% to 70% are converted into heat energy in the form of point vibration.
Since LEDs are semiconductor light-emitting devices, and semiconductor devices themselves change with temperature changes, their inherent characteristics will change significantly. The increase in the junction temperature of the LED will cause the change and attenuation of the device performance. This change is mainly reflected in the following three aspects: (1) Reduce the external quantum efficiency of the LED; (2) Shorten the life of the LED; (3) The main wavelength of the light emitted by the LED is shifted, which causes the color of the light source to shift. High-power LEDs generally use more than 1W of electrical power input, which generates a lot of heat, and it is an urgent task to solve the heat dissipation problem.
2. Several suggestions for improving heat dissipation water products:
1. From the perspective of LED chips, new structures and new processes should be adopted to improve the heat resistance of the junction temperature of the LED chip and the heat resistance of other materials, which reduces the requirements for heat dissipation conditions.
2. Reduce the thermal resistance of LED devices, adopt new packaging structures and new processes, and select new materials with better thermal conductivity and heat resistance, including bonding materials between metals, phosphor mixtures, etc., so that thermal resistance ≤10 ℃/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.