The principle of LED illumination is solid-state illumination. According to the principle of solid-state illumination physics, the spectrum of LED is almost entirely concentrated in the visible light band, so the luminous efficiency is as high as 90%. Therefore, LED is known as the new light source of the 21st century, and will soon become the incandescent lamp and fluorescent lamp. The fourth generation of light source after high-intensity discharge lamps is recognized as one of the top ten cutting-edge technologies. The new illumination source of LED light source will replace the traditional illumination source and is driving a new industrial revolution. Lighting revolution. In response to the global financial turmoil, the Central Development and Reform Commission has allocated 4 trillion yuan together with local financial support. It is estimated that more than 10 trillion yuan will be invested in national transportation, supporting enterprises, and improving infrastructure. Recently, the Ministry of Science and Technology of the People's Republic of China launched the "Ten Cities and Ten Thousand Miles" LED street lighting semiconductor lighting application project in the country. Under this strong east wind, the semiconductor lighting industry, which has consistently received government support, will be an opportunity for great development.
1 System Introduction
A complete LED solar street light system includes: LED light source, controller, battery, solar cell module and lamp body. During the day, the solar cell module converts the light energy into electrical energy and stores it into the battery through the controller. At night, the battery supplies power to the light source through the controller, converting it into light energy and illuminating the road. The lamp body mainly plays the role of system protection and daytime decoration to ensure the normal operation of this cycle. Among them, LED light source, controller and battery are the key to determine the performance of street lamp system. It must be optimized and properly configured in the design.
1 System matching problems Nowadays, manufacturers of solar lamps often pursue excessive styling design, and ignore the most important system matching design. Without careful consideration, they simply calculate things, and finally cause a lot of problems in the lamps; It is not advisable to create the price advantage of your own products and sacrifice the stability of the system.
Matching design is an important factor related to system reliability and stability. To pay attention to it, the following aspects should be considered:
(1) The ratio of solar cell power generation and load power consumption is reasonable.
(2) The ratio of power consumption and battery capacity should meet the requirements of continuous rainy days and the discharge depth is reasonable.
(3) The solar cell charging current and battery capacity ratio are reasonable.
(4) The ratio of load discharge current to battery capacity is reasonable.
2 LED street light technology features The purpose of road lighting is to provide night vision drivers with a visually safe and reliable condition, high-brightness LED street lights, whose brightness must meet the brightness requirements that must be achieved in traffic safety under existing road conditions. Its luminous efficiency and luminous intensity can meet the brightness requirements required for existing road lighting. Road lighting has been implemented since July 1, 2007. The industry standard CJJ45-2006 "Urban Road Lighting Design Standards" of the Ministry of Construction, the road illumination illumination requirements are shown in Table 1. In order to make the design more perfect, the following points should be carefully considered:
