Over the past few years there has been a lot of talk about LED technology that is powered from AC rather than using costly AC to DC drivers, as well as using them to reduce system sizes and cost whilst still proving high quality LED illumination.
In the past however there have been sacrifices in order to obtain these benefits, though recent advances in technology have made a winning proposition making the system reach over 90 percent efficiency.
As you may know, conventional LED lighting systems require a regulated current or voltage to be supplied to the LED, which in turn results in higher costs and shorter life spans. An article by Next Generation Lighting Industry Alliance suggests drivers are responsible for over 50% failure rate of the luminaries they tested.
AC LEDs on the other hand can be connected directly to mains line voltage and completely remove the need for complex drivers.
Having the ability to connect directly to mains power the system become more reliable, offers better design flexibility, lower heat and a far less failure rate, reduced costs, no conversion costs, easier dimming and no external power supply requirements.
Some of the unfortunate drawbacks of AC LEDs are that if the mains voltage is not stable unwanted flickering and flutters will occur, and even at the 50/60Hz it can appear unstable and have the potential to cause headaches and eye strain. Other issues include dimming methods, simply AC LEDs do not like being dimmed by traditional phase shift, or triac dimmers.
Ready for Prime Time
No longer is there a need to sacrifice efficiency, power factor or light quality to gain the perks of using AC LED lights, as time moves forward development in AC LEDs will gain strong ground in retrofit lamps and general lighting applications. There are still challenges to overcome but the future is certainly looking bright for AC LEDs.
Source: LEDJournal - By Vivian Wu