Design And Realization Of Adaptive LED Fill Light Lighting System

Light provide energy for plant growth, development and morphogenesis. The influence of factors such as the geographical position, rainy weather and seasonal change, especially the exacerbated haze weather in recent years, result in lacking of sun as the main factor limiting plant growth. So artificial light supplement is necessary. LED is the best choice to lighting supplement for plant, because LED light source has the advantages of energy saving and high efficiency than traditional light source. With the development of science and technology and widespread application of network communication technology, modern greenhouse gradually entered informatization, intelligent and networked stage. Based on the demand of the light environment for plant, realizing configuration of uniform intensity distribution of LED light source, and lighting system of intelligent, networked, low-energy is the demand of modern greenhouse for plant lighting.In this paper, using LED source module designed as light source, combining with upper computer based on LabVIEW and lower computer controller based on STM32, realize collection, storage, call of environment parameter data, adaptive regulation output of red, green, and blue light, and function of remote monitoring. In this paper, the main research contents are:First of all, LED light source is selected based on theoretical research, and is analyzed with testing instruments. Based on the research of configuration and uniformity, design factors of LED array shape, number of LED, LED spacing and the distance between LED light source and the light receiving surface are set. LED spacing of 7.5mm,10mm,12.5mm and 15mm are raytraced to get irradiance analysis map with TracePro optical software. The optimal design scheme of light-receiving surface evenness design is selected through the comparison and analysis of the irradiation analysis maps, and LED module is implemented.Secondly, PC based on LabVIEW using TCP/IP protocol wirelessly communicate with lower computer through WiFi module. In this paper, a monitoring system is completed through hardware and software design of control module, detection module, WiFi communication module and LabVIEW. LabVIEW achieve remote monitoring of greenhouse via Web publishing function on the front panel.Finally, experimental test and analysis is implemented to LED lighting system we designed. Results show when different lighting sources with different wavelength are lighted, uniformity of light receiving surface is 70%. Effects of system adaptive regulation are also achieved which is ideal. Contrast test is implemented using plant growth chamber between LED lighting supplement system we designed and the traditional constant lighting. Through the comparison and analysis of plant physiological indexes and power consumption, we found system have little differences from traditional constant lighting in physiological indexes, and power consumption saves 40%. It verifies the system has advantages of energy saving, high efficiency, and is of great application value for modern greenhouse production.