Characteristics of LED Drive Power Supply

Good LED lights can not be separated from high-quality LED power supply, so this paper focuses on the characteristics of LED power supply, thus deepening the understanding of consumers of LED power.

(1) high reliability
Especially the driving power of LED street lamp is installed at high altitude, so the maintenance is not convenient and the cost of maintenance is also large.

(2) high efficiency
LED is an energy-saving product, and the efficiency of driving power is high. It is very important to heat the junction of the power supply in the luminaire. The efficiency of the power supply is high, its loss of power is small, and the heat generated in the lamps is small, thus reducing the temperature rise of the lamps. It is beneficial for retarding the decay of LED.

(3) high power factor
Power factor is the requirement of power grid to load. Generally, there are no mandatory indicators for electrical appliances below 70 watts. Although the low power factor of single electrical appliances with small power has little impact on the power grid, the use of large amount of lighting at night, similar loads are too concentrated, will produce more serious pollution to the power grid. For a 30 to 40 Watt LED driver, it is said that in the near future, there may be some specifications for power factors.

(4) driving mode
There are two popular: one is a constant voltage source for multiple constant current sources, each constant current source to each LED power supply alone. This way, the combination of flexible, one way LED failure does not affect the work of other LEDs, but the cost will be slightly higher. The other is the direct constant current power supply, that is, the "China Science Huibao" to use the drive mode, LED series or parallel operation. It has the advantage of low cost, but poor flexibility, but also to solve a certain LED fault, does not affect the operation of other LED problems. These two forms coexist in a period of time. Multi way constant current output power supply will be better in terms of cost and performance. Maybe the mainstream direction in the future.

(5) surge protection
The ability of LED to resist surge is relatively poor, especially the ability to resist reverse voltage. Strengthening protection in this area is also important. Some LED lights are outdoors, such as LED street lamps. Due to the start-up and swing of the grid load and the induction of lightning strikes, various surges may be intruded from the grid system, some of which may lead to LED damage. Therefore, the analysis of "China Science and Technology Huibao" drive power supply in the surge protection should have some deficiencies, and as for the frequent replacement of power supply and lamps, LED drive power to suppress the invasion of surges, to protect the LED from damage.

(6) protection function
In addition to conventional protection functions, it is best to add negative temperature feedback to the constant current output to prevent the LED temperature from being too high; to meet the requirements of safety regulations and electromagnetic compatibility.