Three Applications for High-power LED Light Sources in Public Lighting

At present, flashlights and miner's lamps using white light high-power LEDs as light sources have been widely used and scaled up. Many lighting components manufacturers are using their respective advantages to adopt different design schemes, in the hope that white light high-power LED light source will break through in tunnel lights and street lights. There are three options for applying more:

1. Multiple low power bracket high power LED type:

When designing the luminaire, multiple bracket type low power Φ5~Φ10 white light high power LEDs are used as the light source. At present, there are 1 to 5W bulbs, 15 to 20W tube lamps, 40 to 60W street lamps, floor lamps, etc. on the market. Generally used tens to hundreds of Φ5 ~ Φ10 white high-power LED, array arrangement, power drive can be achieved by capacitor step-down. There is no need to consider too much design, there is no heat dissipation problem, and the structure is easy to implement; but the production process is complicated, the reliability is poor, the failure rate is high, the outer casing size is large, and the brightness of large lamps such as street lamps is not ideal.

2. High-power LED base type:

In some public lighting, such as street lights and tunnel lights, several or more high-power LED bases can be used as the light source. This design idea has greater flexibility in the design of the optical part when designing the luminaire, but different luminaires are more targeted.

The high-power LED light source is a point light source with a light intensity distribution similar to the Lambertian source. If the high-power LED light source is simply collected for road illumination, the advantage of the high-power LED cold light source cannot be truly utilized. Must be achieved through two optical designs. Due to the limited illumination angle of high-power LEDs, the maximum half-light intensity angle can only reach 120 degrees. After multiple combinations, although the illumination can meet the requirements, it does not meet the uniformity requirements of national lighting standards. Through theoretical analysis, it is difficult to achieve uniform light distribution. And the directivity of the high-power LED light source has certain difficulties even through optical design such as a lens.

When designing such a luminaire, if a reflector is not added, a part of the direct light will be wasteful. Even if the angle of the reflector is adjusted, the light band will always exist after reflection, which is the main obstacle that currently plagues its application.

The luminaire adopting this scheme can adopt a switching constant current driving circuit in the power supply driving, and the efficiency is high, up to 80%. However, the luminaire must have a good heat dissipation structure to ensure the service life of the luminaire.

Lamps that use pedestal-type high-power LEDs as light sources are much more expensive than incandescent, fluorescent, and energy-saving lamps, but their energy-saving effects and longevity are much higher than other lamps. If it is used on street lamps, its one-time investment is higher, but long-term power saving effect and economy are worth looking forward to.

3. Single or several multi-chip integrated type

Multi-chip integrated white light high-power LED has unique advantages: through different series-parallel combination, it can realize various rated voltage and current, better adapt to driver design, improve overall luminous efficiency and reduce cost; chip per unit area The number can be more or less, and can be packaged into a variety of different point and surface light sources.

The installation process of the lamp is simple, and the secondary optical design is difficult due to multi-point illumination. Since the average single can be made to 20W or even 200W, the heat dissipation requirements for the lamps are also harsh. The luminaires are designed to be less flexible and subject to chip limitations.

Since high-power LED chips have not been domestically produced so far, they are imported from abroad or Taiwan, and the price is very high. However, the domestic supply of small-power chips is sufficient, and the same power is combined, and the price is relatively low. Therefore, by packaging a plurality of small power chips to form an integrated white light high-power LED, the use of the light source of the lamp has a price advantage.

You can also read details of related led lingting components: COMP-7-VARTA/WITH LEADS(BLACK & RED)