No electrolytic capacitor as a LED price war as innovation

Associate professor of Guangxi University Wang Xitian specializes in the design of power supply design in recent years, and actively participate in the LED power supply, especially the thorough research in the field of non electrolytic capacitor. For the current LED lighting industry difficulties and countermeasures, Wang Xitian also has its own unique insights.

Energy Star LED lighting standard and promote the healthy development of industry

Industry popular saying: "first-class standard in making profit, profit rate in the patent competition, three profit in the brand strategy, four profit is the price war has milepost meaning".2009 November announcement of the "American Energy Star LED lighting standards". Although the purchase is only a "Energy Star certification" logo of the LED lighting market in the United States, the United States government to enjoy financial subsidies to buyers, but this is the first standard LED lighting industry global LED lamp can not focus on, even in the future will become an important reference in the formulation of national LED lighting standard.

Wang Xitian summarizes the core content of the standard in four sentences: 1, reduce the power factor threshold, helps to reduce the cost and expand the LED lamp production; 2, outstanding small power LED bulb directly replace incandescent lamp standard; 3, clear LED lighting luminous efficiency of 55 lumens per watt, clear bottom line; 4 the use of 25000 hours after the three become the bottom line of light.

With LED bulbs directly replace incandescent bulbs with energy-saving significance, now the domestic chip has reached 80lm/W, with the United States Energy Star specification, replacing incandescent bulbs with LED lighting specifications shown in the table below:

Wang Xitian stressed that this is only for domestic LED now 80lm per watt light efficiency statistics. Foreign countries have announced a new product of 208 lumens per watt LED lamp, incandescent lamp is only 15-25lm per watt low light efficiency, so the use of LED lamps instead of incandescent lamps is an inevitable trend.

LED industry chaos and worries

LED lighting development, but chaos, such as lamp life did not imagine it in thirty thousand hours. Wang Xitian believes that the industry must face the following problems:

LED unit 1, the purchase of high light efficiency, attention by the high temperature of 60 DEG C under LED voltage and current data to screen. Select the current consistent LED is suitable for series, select the same voltage LED is suitable for the association. At present, the folk workshop type LED lamp factory, if the LED after the purchase of 60 degrees high temperature screening, can have confidence in a process to promote, otherwise it will cause a lot of quality problems.

2, small power LED lights, a LED, a constant current power supply; and, in the high power LED lamp string LED respectively to the constant current power supply, which is more complicated; there are both on the grid network structure and LED matrix, constant current and voltage must be the power supply is good.

3, LED light is the sworn enemy of high temperature, the volt ampere characteristics of LED unit are quite different in different temperature. Therefore, in addition to the screening of LED at 60 degrees LED were used in series and parallel to the LED, but also the need for temperature monitoring and compensation, can be used to control the temperature of the light bulb to minimize the temperature rise. LED the higher the temperature Zeguang efficiency is low, the light effect is inversely proportional to temperature; the higher the temperature of LED light is, life is inversely proportional to temperature. It is no exaggeration to say, who mastered the LED lamp heat dissipation ratio, excellent structure, who will get the advantage of LED lamp industry confidence. The LED lamp power adapter, pay attention to the electrolytic capacitor on the temperature sensitive products: electrolytic capacitor mark of 85 DEG C; industrial electrolytic capacitor temperature mark 105 DEG C; professional grade products of electrolytic capacitor mark temperatures above 125 degrees. Penny goods, high reliability from the purchase of electrolytic capacitor began to pay attention to the.

4, LED lighting is the combination of science and art, including light illumination (Lux "as a unit, such as a hallway lights under 15 lux can, desk and church should have 60 lux desktop more than satisfied).

And "color" and "color" and the need for dimming and optical requirements, and meet the psychological needs of the eyes. For this purpose, the LED luminaire itself needs to be considered in terms of power electronics and thermodynamics, and overall, there are cost limits and volume requirements, etc.. Therefore, the LED industry easy entry, the threshold is not high, prone to herd, when the above art, optics, electricity, thermodynamics of specific problems, and there will be many goukan, once a reshuffle.

Current LED lighting power factor more than 0 orders are required, 9, Wang Xitian did not agree with this requirement. Fluorescent lamp electronic ballasts are widely used, the formation of social consensus: the higher the power factor, the better. But in order to improve the power factor had to raise costs, which are detrimental to production and marketing. Moreover, the fluorescent lamp is a low pressure arc discharge lamp, is a negative resistance characteristics of the light source, the power of environmental protection (harmonic), EMC problem is very prominent. However, LED is a positive resistance characteristics of the light source, LED lamp itself does not exist EMC problem, only for the LED service of the constant current power supply. Such as switching power supply, EMC problems. The United States has a general online harmonic compensation device, so the 5W or less than 5W of the LED bulb does not require PF, even more than 5W of the LED bulb, but also to reduce the threshold requirements only 0, or more on it. Do not have to join the same number of active power compensation APFC switching power supply (which will lead to the EMC problem), is very beneficial to reduce production costs. This is to promote the production and sale of LED bulb standardization purposes.

"Have a brilliant future without electrolytic capacitor scheme"

Now only LED factory manual