According to the characteristics of the power grid and the power supply of LED, the following points should be taken into account when selecting and designing the LED drive power supply:
1 high reliability, especially the LED street lamp drive power, installed in the high altitude, maintenance is not convenient, the cost of maintenance is also large.
2 high efficiency LED is energy-saving products, drive power efficiency is high. For power supply installed in the lamp structure, is particularly important. Because the luminous efficiency of LED decreases with the increase of LED temperature, the heat dissipation of LED is very important. High power efficiency, its power consumption is small, heat in the lamp is small, LED drive power reduces the temperature rise of lamps and lanterns. Favorable to delay the LED attenuation.
3 high power factor power factor is the requirement of power grid to load. Generally less than 70 watts of electrical appliances, there is no mandatory indicators. Although power is not a single electrical power factor low point on the grid has little effect, but all night lighting similar load is too concentrated, will cause serious pollution to the power grid. For 30 watts ~40 watts LED drive power, it is said that in the near future, there may be some indicators of the power factor requirements.
4 driving mode now has two kinds: one is a constant pressure source for multiple constant current source, each constant current source to separate each road LED power supply. This way, the combination of flexible, all the way LED fault, does not affect the work of other LED, but the cost will be slightly higher. The other is direct current power supply, LED series or parallel operation. It has the advantage of low cost, but poor flexibility, but also to solve a LED failure, does not affect the operation of other LED issues. These two forms coexist in a period of time. Multi way constant current output power supply, in terms of cost and performance will be better. May be the future of the mainstream.
5 surge protection LED anti surge capacity is relatively poor, especially the anti reverse voltage capability. It is also important to strengthen the protection of this area. Some LED lights are installed outdoors, such as LED street lamps. Due to the load of the power grid and lightning induction, from the grid system will invade a variety of surge, some surge will cause damage to LED. Therefore, LED drive power supply to suppress the surge of intrusion, the protection of the ability of LED is not damaged.
6 protection function in addition to conventional protection function, it is best to increase the LED temperature in the constant current output negative feedback to prevent the LED temperature is too high.
7 protection lamp installation type, power structure should be waterproof, moisture-proof, shell to light.
8 the life of the driving power supply is suitable for the life of LED.
9 to meet the requirements of safety and electromagnetic compatibility.