Countries are actively promoting the implementation of energy-saving and emission-reduction projects. In particular, LED street lamps in China are &#118alued by LED street lamp manufacturers due to their huge business opportunities. Street lamps are an important part of urban lighting. Traditional street lamps often use high-pressure sodium lamps. The overall low light efficiency of high-pressure sodium lamps causes a huge waste of energy. Therefore, the development of new types of high efficiency, energy saving, long life, high color rendering index, and environmental protection The street lights are of great significance to the energy saving of urban lighting.
Features of today's LED street lights:
The difference between high-power LED street lights and conventional high-pressure sodium street lights is that the light source of high-power LED street lights adopts low-voltage DC power supply, high-efficiency white light diodes composed of GaN-based power blue LEDs and yellow phosphors. Light Emitting Diodes LED) is a high-efficiency solid-state light source formed by a semiconductor PN junction that can emit light with weak electric energy. Under a certain forward bias voltage and injection current, the holes injected into the P region and the electrons injected into the N region diffuse to the After the source area, the radiation recombines and emits photons, which directly convert electrical energy into light energy.
As the light source of street light, LED has many advantages compared with traditional street light source.
1. The LED street lamp itself has the directivity of light, and there is no light diffusion to ensure the light effect;
2. The LED street lamp has a unique secondary optical design, which irradiates the light of the LED street lamp to the area that needs to be illuminated, that is, the road surface, which further improves the light efficiency and achieves the purpose of energy saving;
3. The light source efficiency of LED has reached 100lm/W, and there is still a lot of room for development. The theoretical &#118alue can reach 250lm/W. The luminous efficiency of high-pressure sodium lamps increases with the increase of power. Therefore, the overall light efficiency LED street lights are stronger than high-pressure sodium lights;
4. The light color rendering of LED street lamps is higher than that of high pressure sodium lamps. The color rendering index of high pressure sodium lamps is only about 23, while the color rendering index of LED street lamps can reach 75 or more. From the perspective of visual psychology, the same brightness can be achieved. It is more than 20% lower than high-pressure sodium lamps (refer to British road lighting standards); moreover, at the intermediate vision level, the human eye can distinguish things more easily in a high color temperature environment than in a low color temperature environment, avoiding certain dangerous states;
5. The light decay of LED street lights is small, less than 3% in one year, and it can still meet the road illumination requirements after 10 years of use. Therefore, LED street lights can be designed with lower power than high-pressure sodium lamps;
6. LED street lights can be automatically dimmed, which can meet the lighting requirements at different times, reduce the power as much as possible, and save energy;
7. LED is a low-voltage DC device, and the voltage to drive a single LED is a safe voltage, so it is a safer power supply than using a high-voltage power supply, especially suitable for public places. The characteristic of direct current makes LED especially suitable for combining with solar energy and wind power;
8. The LED die of each unit has only a small volume, so it can be prepared into various shapes of devices, and it is suitable for a changeable and shock-prone environment;
9. Long life: The theoretical life can be used for more than 50,000 hours;
10. The LED can be switched frequently without worrying about its damage;
11. Easy to install: directly install the LED street lamp cap on the pole to replace the original sodium lamp cap