Lighting consumes nearly 20% of the global electricity. Compared to developed countries, a higher proportion of lighting energy consumption in developing countries. The incandescent Although cheap, but the efficiency is very low. If the overall energy saving bulbs to replace or solid-state lighting (led lights), the world can reduce the construction of more than 100-seat power plant, and reduce thousands of tons of carbon dioxide emissions each year. The European Union has plans in the 2009-2016 phase-out of incandescent; the United States is also expected to gradually disable most of the incandescent 2010-2014. Although Japan has not passed a similar legislative measures, a leading lighting brands, Toshiba has been in the March 2010 closure of its incandescent production line, ending 120 years of manufacturing light bulbs history. On the other hand, China is actively build its large-scale LED lighting industry. China, India, and Japan to ban incandescent, but also within a few years things will happen.
Eliminated from the incandescent lamp, general household and commercial lighting energy saving bulbs, CFL and LED lighting planes a competitive situation. LED lighting and many other features beyond saving light bulbs, and therefore parties are optimistic for the lighting of choice for the twenty-first century. The advantages of LED lighting include:
LED does not contain toxic substances, energy saving bulbs have a certain amount of mercury.
Unlike the energy saving bulbs, the LED does not emit ultraviolet rays.
LED lighting efficiency and energy saving bulbs are similar, but its efficiency is constantly increased, while prices are getting cheaper.
LED lamp life several times longer than the energy saving bulbs. Matsushita Electric of Japan to claim that their LED bulbs have a life span of 19 years.
5 LED bulbs in the low temperature of -40 degrees C environment to continue its normal operation, but most of the energy saving bulbs in less than 10 degrees C, it is difficult to start or operate.
Many industry analysts predict that LED bulbs in 2015 to replace the energy saving bulbs. This view is the conclusion of the competition in other markets based on recent years, LED and CCFL products. They noted that the LED backlight CCFL backlight, mobile phones, tablet computers, notebook computers, the application has been pushed to the brink of elimination, the market experts confidently predict LED backlight CCFL backlight in the LCD TV and LCD screen will replace the 2012 applications. In this respect, beyond the CFL lighting LED lighting in five years it is reasonable to speculate.
Many engineers and companies in the LED lighting technology breakthrough achievement for us to bring this lighting revolution, we applauded them pay tribute. However, we are very anxious about the potential destroyer of the silicon-controlled dimmer will erode, or even overthrow the majority of the benefits of LED lighting revolution.
We know that the dimmable lighting energy-saving effect can be further enhanced. However, in the three main types of LED dimming lighting, silicon-controlled dimmer like a hideous monster, swallowing our efforts to develop the results obtained by the dimmable lighting.
The silicon-controlled dimmer, dimming the truncated part of the bulb of the sinusoidal alternating current waveform. As a result, the power factor of the silicon-controlled dimming light bulb is often less than 0.5. But note that the power factor is an important indicator of the power supply efficiency and power quality. The perfect power factor of 1.0. Only with the phase of the sinusoidal current, and harmonic distortion is zero, in order to achieve a 1.0 power factor. In recent years, the current waveform harmonic distortion of the electrical and electronic equipment, EN / IEC 61000-3-2 standards are very strict specification. In the past, most of the computer power supply power factor of 0.5 to 0.7. EN 61000-3-2 and other government specifications require the power of television, computers and other electrical equipment, such as the U.S. Department of Energy’s Energy Star 0.9 power factor.
Furthermore, the silicon controlled dimming LED bulbs must be coupled with some capacitor snubber circuit in order to avoid the light bulbs flicker when dimming. But doing so will make the already low power factor becomes lower, often less than 0.10. At the same time, the supply line current waveform will become a series of surge current. The current waveform harmonic distortion will far exceed the prescribed limits. The author of more than three decades of experience in the electronics industry point of view, there is no any other product like the silicon-controlled dimmer, like power factor and current waveforms caused such a serious injury.