The secrets of LED street lighting technology
LED lighting industry, lighting lighting project, is well received by the global environment, the industry also has its particularity. And it is precisely the most important power LED lights LED current development of LED technology related to the design, there are already a variety of programs and unique design approach, Here we look at the little secret LED street lighting technology.
1, LED street lamp power supply constant Why must it?
LED lighting characteristics determine the material influenced by the environment, such as elevated temperature, LED current increases, the voltage increases, the LED current will increase. Long-term than the rated current work, will greatly shorten the life of the LED lamp beads. The LED constant is change when environmental factors such as temperature and voltage, to ensure that the operating current value unchanged.
2, LED street lamp power supply current precision
Precision constant current power supply on the market, some difference, as the popularity of the recommended programs such as constant current program error of ± 8%, constant error is too large. General requirements in the ± 3% on it. By 3% of the design. To fine-tune the production of power in order to achieve ± 3% error.
3, LED street lamp power supply operating voltage
General LED's recommended operating voltage is 3.0-3.5V, have been tested, most of the work in 3.2V, 3.2V calculated according to the formula so reasonable. N-series lamp beads total voltage = 3.2 * N
4, LED street lamp power supply operating current is how much is the most appropriate
Such as LED's rated current 350 mA, and some plants used to make the outset, design 350 mA, in fact, this current work is very serious fever, after numerous comparison test, designed to be 320 mA is ideal . Minimize the amount of heat, so that more energy into visible light energy.
5, series-parallel LED lights with wide voltage power supply board to be more wide it?
To make LED lights power supply input voltage range is wide in scope AC85-265V, the light board parallel LED strings is very important. Try not to use a wide voltage, can be divided into AC220V, AC110V classification possible, so as to ensure the power supply reliability. Due to the current supply is generally a non-isolated step-down constant current power supply, requiring voltage 110V, the output voltage should not exceed 70V, serial number no more than 23 strings. When the input voltage is 220V output voltage can reach 156V's. That is, no more than 45 number of series strings. Parallel few not too much, otherwise the operating current is too large, the power fever serious. There is also a wide voltage scheme, APFC active power compensation is the first with the L6561 / 7527 of the voltage raised to 400V, then the buck, the equivalent of two switching power supply. This scheme was used under certain conditions.
6, isolated / non-isolated
Usually made of isolated power as 15W, the LED lights on the power tube transformer bulky, difficult to put in here. Mainly to see the spatial structure, as the case may be, isolated generally only do 15W, 15W more than the few and the price is very expensive. So the cost is not high isolation, the general non-isolated more mainstream, the volume can be made smaller, the smallest high 8 mm can be done, in fact, non-isolated safety measures well, the problem does not exist. Space allowed isolated power can do.
7, LED street lamp power dissipation
The main factor is the cooling solution power LED lights beads in hot conditions, but can greatly extend the life, usually with aluminum and easier to heat. That is, the power LED lights beads attached to the aluminum plate, external to maximize heat dissipation area.
Faced with such a vast LED market is really full of vigor, mainly to develop science can achieve a leading position on a few technical areas, I believe that China's LED business will become more powerful.