Studies On LED Dimming Controller With Sunlight Perception Function

With the increasing emphasis on the healthy lighting environments of lighting, the studyof the impact of lighting on eco-environments has been carried out in depth in many countries.Ecological healthy lighting will be the direction of the research and application of lightingfield. For humans is no more as simple as illuminate, and environment friendly, it is requiredto be healthy, comfortable, energy saving. For all living creatures sun is the healthiest lightsource, full use of daylight for lighting is an important way to realize green lighting.The means of traditional lighting controlling is very single and the degree of intelligenceis also low. The switch and dimming controlling are done. Basing on the people`s subjectivefeelings, lacking of proper light control strategies, In low light conditions, the light sourcecan`t be adjusted in an adaptive manner to keep the room maintaining a constant illuminationlevel.In the course of indoor lighting, illumination of the working surface is often affected bythe movement of persons. When people are closing to the working surface, the illuminationvalue decreased due to his blocking of incident light. While the people left, the illuminationlevels regain its original height again. If we use the classical control technology and theillumination of the working surface as the control variables in order to maintain a constantillumination, it inevitably lead to flashing light and thereby reducing the comfortableness oflighting.This research focused on the study of LED dimming controller with daylight sensingfunction, and the results are work as follows：The LED dimming controller with daylight sensing function is composed mainly ofillumination measurement unit, a data processing unit, high-power LED driver unit andremote control units. The LED dimming controlled technology with daylight sensing ismainly compromises the technology of automatic control, Pulse width modulation dimming,sensing and communication and so on. Through the hardware selection and circuit design, thesystem can dynamically adjust the brightness of the LED light source based on the strength ofthe sun. when sunlight is insufficient, indoor illumination can be controlled through the jointaction of the sun and artificial sources. Illumination is automatically maintained at thethreshold value, to achieve the purpose of saving energy while ensure the good effects oflighting. By illumination equivalent processing, the dimming controller will equivalent theintensity of illumination of the working surface and the intensity of illumination near thelighting. By shortening the feedback circuit, it is possible making the system compact andeasy to install.The dimming controller has a variety of driving modes, modular design and multiplefunctions to be as option. The dimming controller has broad application prospects in homelighting, commercial lighting and other fields. The study shows that in the case of sunshineshortage, such as dawn, dusk or overcast, it can achieve at least40%energy savings for thedaylight sensing LED technology.