Analysis of the development trend of future LED dimming methods

Since the LED light source enters the field of general illumination, it gradually replaces the traditional light source and increasingly occupies the core field of illumination. In addition to the advantages of low energy consumption, no pollution, no mercury, long life, and strong controllability, the LED light source is distinguished from the traditional light source. Therefore, give full play to the innate advantages of LED, let LED be "controllable and adjustable" according to people's lighting needs, which will make LED occupy the core position of lighting field more quickly. How to achieve cost-acceptable "controllable adjustment" will be very important.

The demand for dimming can be roughly divided into three categories: one is the need to adjust the light of function type, such as the entrance to the door, the conference room, etc.; the second is the embodiment of the comfort and lifestyle of the home life, such as the light and dark combination of the light, the color temperature Cold and warm, can be adjusted according to the needs of the environment, can also play a role in setting off the atmosphere; Third, the need for environmental protection and energy conservation, such as energy-saving needs in public places. Such as parking lot lighting, shopping mall lighting, road lighting, etc.

At present, according to the way of dimming, we can also be roughly divided into: thyristor dimming, remote dimmer wall switch and some commercial lighting dimming systems, such as 0-10V, Dali and so on.

How to provide cost-effective LED products to consumers according to the needs of dimming and appropriate dimming methods will be the key to testing the industry.

The thyristor dimmer is a product that meets people's needs for dimming halogen lamps. Because there is no need to change the wiring, the device cost is low, and the popularity of European and American households is high. Therefore, thyristor dimming technology will exist as an existing dimming method in the replacement market. However, it is undeniable that thyristor dimmers also have great shortcomings. include:

The power factor will be poor, and the shorter the conduction angle, the worse the power factor will be. When adjusted to 1/4 bright, the power factor will be lower than 0.25.

In the dimming state, the electromagnetic compatibility will be very poor.

The efficiency is poor, because when the dimming, the load is insufficient, the silicon control tube will be closed early, causing the LED lamp to be unable to work stably, and the problem of flickering may occur. To solve the flicker problem, a bleederordummy load is usually added to maintain the normal operation of the silicon control tube by consuming power on the bleeder resistor. In this way, there is a waste of energy, which is contrary to the original intention of dimming and energy saving. At light loads, the thyristor dimmer system is only about 10% efficient.

At the same time, the matching problem is also a very serious problem. To develop a thyristor dimmer with dozens of brands on the market, it is quite difficult to ensure compatible dimmable LED lamps.