Chang Hui analyzes the design experience of solar street lights

1. Positioning When we develop a new solar street light, we must first have a position for the street light (developing the lamp condition table, such as the overall structure of the lamp, power requirements, electrical performance indicators, luminous efficiency, protection performance, expected weight Etc.) At present, many people don't have a thorough understanding of solar street light systems, and there are still many deficiencies. 2. The heat dissipation treatment can calculate the number of our LEDs and the approximate power of the heat source based on the luminous flux, and then the design of the heat dissipation system can be carried out. Here we design a temperature rise limit, for example, when the ambient temperature is 25 degrees, not more than 25 degrees. , And then calculate the thermal resistance of the system. It should be noted that the direction of the heat sink is generally parallel to the axis of the road. The better design of the heat sink fins should be a structure with a small upper part and a larger lower part, and the thickness of the lower part of the fin is preferably 5mm (depending on the thermal power) Above, the depth should preferably not exceed three to four times that of the fin, because the denser the heat flow, the worse the heat dissipation effect. The bottom thickness of the radiator can be designed to be thinner, such as no more than 3mm, to reduce the weight of the product. 3. Optical considerations The design of the luminaire is best so that the light emitted by the LED closest to the wall of the lamp body will not be blocked. The inner wall of the luminaire can be made to a certain angle if possible, of course, it can also be treated with chrome plating to obtain Better light output. It is more common to add a reflector, which can increase the utilization rate of stray light, which can increase by more than 15%.　　4. Structure 　　 Generally speaking, I recommend the tempered glass solution, because the performance is more stable compared to the PC lens exposed solution. PC material has many problems in terms of weather resistance, and it is difficult to solve the problem of waterproofing due to stress. In order to be suitable for different installation conditions, the installation should be convenient, the angle can be adjusted, and the radiator exposed will be better.　　5. Electrical aspect 　　 The most suitable solution for general 1W LED is still 350mA drive. (In terms of heat, electricity, and stability, there are now many LEDs with thin-film chips. The higher the current, the worse the reliability.) The better way is to open the constant current part separately, and each channel is independent of constant current. It is worth mentioning that Today's LEDs are packaged, so there is no need to add another LED.