The LED Lighting Technology Drived Directly By Alternating Current

Although the light-emitting diode(LED) has been put into manufacturing more than ten years, all of the LED luminaires available in the market are drived by direct current(DC), so AC/DC conversion is needed when the alternating current(AC) power is supplied. This not only increases costs of the LED luminaires, but also reduces greatly the service life of them, furthermore, results in energy waste. All kinds of the problems above mentioned would be solved by the LED lighting technology drived directly by alternating current(AC LED) which discussed in this paper. Using the single-phase conductivity of LEDs as diodes, rectifier bridge circuit can be builded, alternating current is input, through the bridge, the output is direct current, which can drive directly LED. Without transformer and driving circuit of constant current source, AC LED has many advantages, such as convenient application, low cost, etc. In addition, less heat would be producted because of only half of LEDs in rectifier bridge working.The principle of rectifier bridge circuit is elaborated firstly as well as AC LED technology which combines LED and rectification theory. Whereafter, the basic circuit of AC LED and various power AC LED circuits(for example5W,10W) are introducted in detail, meanwhile, the simulations of every circuit using Multisim are described, too. The simulation results are consistent with theoretical analysis. In the end, according to the previous circuit designs and simulation results, printed circuit boards (PCB) are designed by Altium Designer, in addition, some circuits are validated and analysed, and it’s found that PCB board circuit verification results according basically with previous simulation results.It’s worth noting that the PCB board-level circuit is not the only form of AC LED. In accordance with the above ideas, deeper integration could be made as needed, such as using surface mount devices, or even using directly die. AC LED technology is unique new and practical, has many advantages. It’s one of the trends of the developments of LED lighting technology.