Nine performance characteristics and requirements of LED drive power
According to the power grid rules and LED drive power requirements, the following nine performance characteristics must be taken into account when selecting and designing the LED driver power supply:
1. High reliability Especially like the driving power source of LED street lamps, it is installed at a high altitude, which is inconvenient to maintain and costly to repair.
2. High-efficiency LEDs are energy-efficient products that drive power supplies with high efficiency. The structure of the power supply installed in the lamp is particularly important. Because the LED's luminous efficiency decreases as the LED temperature increases, the heat dissipation of the LED is very important. The efficiency of the power supply is high, its power consumption is small, and the heat generated in the lamp is small, which also reduces the temperature rise of the lamp. It is beneficial to delay the decay of the LED.
3. High power factor The power factor is the grid's load requirements. Electrical appliances below 70 watts are generally not mandatory. Although the power factor of a single appliance with low power has a little lower impact on the power grid, at night, everyone lights up and the similar load is too concentrated, causing serious pollution to the power grid. For the 30-watt to 40-watt LED driver, it is said that in the near future, there may be certain indicators of power factor requirements.
4. Drive mode There are two kinds of current pass: One is a constant voltage source for multiple constant current sources, and each constant current source supplies power to each LED individually. This way, the combination of flexible, all the way LED failure, does not affect the work of other LEDs, but the cost will be slightly higher. The other is a direct constant current supply with LEDs running in series or in parallel. Its advantage is that the cost is lower, but the flexibility is poor, but also to solve a certain LED failure, does not affect the operation of other LED. Both forms coexist for a period of time. Multiple constant current output power supply methods will be better in terms of cost and performance. It may be the mainstream direction in the future.
5. Surge protection The ability of the LED to withstand surges is relatively poor, especially against reverse voltage capability. It is also important to strengthen this protection. 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 can be invaded from the grid system, and some surges can lead to LED damage. Therefore, the LED drive power must have the ability to suppress surges and protect the LED 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. Protective aspects of the lamp outside the installation type, the power structure should be waterproof, moisture-proof, shell to be light.
8. The life of the drive power supply must match the life of the LED.
9. To meet safety and electromagnetic compatibility requirements.