LED power driver is a voltage converter, which can make a power supply convert into a specified voltage and current to drive the LED light. According to the rules of using electricity and the performance requirements of LED driver, we need to consider the following points when we select and design the LED power driver.
(1) High reliability. LED power driver, especially the driving power of LED street lamp, needs to meet the high reliability because the maintenance is convenient and the maintenance cost is high.
(2) High efficiency. LED is an energy-saving product so it requires a high drive power. The structure of power supply installed in the lamp is particularly important because the luminous efficiency of LED can decrease with the LED temperature increasing. Therefore, the heat radiation is very significant. Because of high efficiency power supply and low power loss, the heat value is small in the lamp and it reduces the temperature rising of lamps, which is beneficial to delay theluminous decay of LED.
(3) High power factor. Power factor is the load requirements of power network. Generally, electrical appliances of less than 70W have no mandatory index.That electrical power has little influence on the power grid, but in the evening, the similar load is too concentrated to bring the serious pollution to power grid.For the 30 to 40W LED driverpower, it is said that in the near future, there may be some requirements of the indicators on the power factor.
(4) Driving modes. Now there are two kinds of commonly use: The one is thata constant voltage source provides a plurality of constant current sources, and each of the constant current sources isseparatelyfor each LED power supply.In this way, the combination is flexible, even if one way of LED is fault, it will not t affect other LED's work. But it will cost a little higher. The other one is a direct constant current power supply. And LED is in the series or parallel operation. It has a little lower costbut poor flexibility. We need to solve a certain fault of LED, and we can’t affect other LED operation. In a certain time, the two forms exist together. The modeof multi-channel constant current output power supplywill be better in the cost and the performance. Perhaps it is the mainstream direction of the future.
(5) Surge protection. LED anti surge capacity is relatively poor, especially the ability of anti-reverse voltage.It is also important to reinforce the protection.
(6) Protection function. Except for the conventional power protection function, it is necessary to set up a negative feedback of LED temperature, which can eliminate high temperature.
(7) Protection. The lamp is mounted outside, and then the power structure should be waterproof, moisture proof and sun-proof.
