LED drive power input, including high-voltage power frequency AC (ie, electricity), low voltage DC, high voltage DC, low voltage high frequency AC (such as electronic transformer output) and so on. While the LED drive power output is mostly with the LED forward voltage drop to change the voltage constant current source.
According to the power grid rules and LED power supply driven by the characteristics of the choice and design of LED power supply drive to take into account the following points:
1. High reliability, especially as LED lights drive power, installed at high altitude, maintenance is not convenient, maintenance costs are also large.
2. High efficiency LED is energy efficient products, drive power efficiency is higher. It is especially important for the power supply to be installed in the fixture. Because LED luminous efficiency with the LED temperature increases and decreased, so the LED heat is very important. Power efficiency is high, its power consumption is small, the heat in the lamp is small, it will reduce the temperature rise of the lamp. To delay the LED light failure beneficial.
3. High power factor power factor is the load on the grid requirements. Generally less than 70 watts of electrical appliances, there is no mandatory indicators. Although the power is not a single power factor low power on the power of the little impact, but at night we light, similar load is too concentrated, will produce more serious pollution of the grid. For 30 watts to 40 watts of LED drive power, it is said that in the near future, there may be a certain degree of power factor requirements.
4. There are two ways to drive now: one is a constant pressure source for multiple constant current sources, each constant current source to each LED power supply. This way, the combination of flexible, all the way LED failure, does not affect the work of other LED, but the cost will be slightly higher. The other is a direct constant current power supply, LED series or parallel operation. Its advantage is that the cost is lower, but the flexibility is poor, but also to solve an LED failure, does not affect the other LED operation problems. These two forms coexist for a period of time. Multi-channel constant current output power supply, in terms of cost and performance will be better. Perhaps the future direction of the mainstream.
5. Surge protection LED anti-surge capability is relatively poor, especially anti-reverse voltage capability. It is also important to strengthen this protection. Some LED lights installed in the outdoors, such as LED lights. Due to the load of the grid load and lightning induction, from the grid system will invade a variety of surges, and some waves will lead to LED damage. So the LED drive power to suppress the surge of intrusion, the protection of LED is not damaged capacity.
6. Protection function In addition to the 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 aspects of lighting outside the installation type, the power structure to waterproof, moisture, the shell to light.
8. The life of the drive power supply is compatible with the life of the LED.
9. To meet the requirements of safety and electromagnetic compatibility.
With the growing use of LED, LED power supply performance will be more and more suitable for LED requirements.