At present, almost every electronic appliance (without batteries) in world needs to work under AC. And also we electricity networks around us also provide alternating current, such like household electricity, industrial and commercial electricity. When DC-applying LED lighting products start to emerge on the market, problems came forward too. Every LED lamps should be used together with transformers. Since LED chips are very sensitive to voltage variations, ordinary transformers are not competent. LED manufactures have to design special transformers typically used for LED lighting products, for example high-frequency electronic transformers.
In practices, AC-DC conversion devices came up with other problems: 1. During the process of AC-DC conversion, nearly 15%-30% electricity will be transferred into heat energy and completely wasted. That is contrary to the LED lights high lighting efficiency and energy saving concepts. 2. In most cases, designing and producing a suitable transformer will cost manufacturer a lot of money. It also increases the cost of LED lamps virtually. 3. Electronic components within AC-DC conversion devices have a relatively short service life. This makes LED drives (AC-DC conversion device embedded) became the most fragile parts of the entire LED lamps. 4. Under DC voltage, LED lamps maintained in a constant-working state. This is rather harmful internal electronic components, causing huge working temperatures, and consequently the light attenuation of LED chips.
In order to solve the above problems, some LED producers put forward a new concept – AC-LED technology. Literally, it is a technology that can make LED lamps directly used under AC without any transformers. AC-LED technology used principles of rectification circuit. However, since AC periodically changed, visible flickers are irresistible.
There are now two solutions for this problem: 1. Using series circuit to improve the wave and increase the power factor simultaneously. But this will also reduce the efficiency. 2. Using parallel circuit to smooth the wave. Although flickers cannot be removed completely, filtering capacitors are able to alleviate this phenomenon.
SunFor has recently found a way to decrease flickers caused by AC-LED technology: using phosphor powder. Light emitted through this new developed phosphor powder will have an obvious delay under AC. After applying this phosphor powder, lamps will only present a tiny alternating between light and dark.