According to the power consumption rules of the power grid and the characteristics of the LED drive power supply, the following points should be considered when selecting and designing the LED drive power supply:
1. High reliability: Especially like the driving power of LED street lights, it is installed at high altitude, it is difficult to repair and costly.
2. High efficiency: LED luminous efficiency decreases with increasing temperature, so heat dissipation is very important. Especially the power supply is installed in the luminaire
LED is an energy-saving product, the driving power supply has high efficiency, the power consumption is small, and the heat generated inside the lamp is small, which is beneficial to reducing the temperature rise of the lamp. Delay LED light decay.
3. High power factor: The power factor is the load on the grid. Generally, there are no mandatory indicators for electrical appliances below 70 watts. Although the power factor of a single power consumer with low power has little effect on the power grid, at night, everyone lights up, and the similar load is too concentrated, which will cause serious pollution to the power grid. For 30 watts to 40 watts of LED driver power, it is said that in the near future, there may be certain indicators for power factors.
4. Constant current output power supply mode;
1) Multi-channel constant current output, flexible combination, one-way LED failure, does not affect other LED work, the cost is slightly higher.
2) Direct constant current power supply, LEDs run in series or in parallel. The cost is lower, but the flexibility is poor, and one LED failure affects other LEDs.
These two forms coexist for a while. Multi-channel constant current output power supply mode will be better in terms of cost and performance. Perhaps it is the mainstream direction in the future.
5. Surge protection: LED's ability to withstand surge is relatively poor, especially against reverse voltage capability. It is also important to strengthen protection in this area. Some LED lights are installed outdoors, such as LED street lights. Due to the start of the grid load and the induction of lightning strikes, various surges will be invaded from the grid system, and some surges will cause LED damage. Therefore, the LED driver power supply must have the ability to suppress the intrusion of surges and protect the LEDs from damage.
6. Protection function: In addition to the conventional protection function, it is better to increase the LED temperature negative feedback in the constant current output to prevent the LED temperature from being too high.
7. Protection: The exterior of the lamp is installed, the power supply structure should be waterproof and moisture-proof, and the outer casing should be light-resistant.
8. The life of the drive power is adapted to the life of the LED.
9. To comply with safety and electromagnetic compatibility requirements.