LED upravljanje osvjetljenjem s podesivim CCT-om i CRI-jem

In recent years, with the continuous development of LED lighting industry, LED has gradually entered the field of general lighting with the characteristics of high luminous efficiency, adjustable brightness, easy control, long service life and various colors. With the development of technology and the improvement of people's quality of life, the adjustable color temperature, high color rendering and intelligent LED lighting system have been paid more and more attention. In view of the shortcomings of inaccurate adjustment of color temperature, poor color rendering and inconvenient control in LED application, the method of obtaining color temperature adjustable white light by mixing cold and warm white LED, the method of improving the color display of light source by multi base color LED chip, the method of obtaining wide color temperature adjustable and high color display white light by wrgb LED module, the theory analysis and engineering design of indoor lighting control system are completed, and the corresponding experiments are carried out.

1. Through the model of mixed color of cold and warm white LED with dual channel pulse width modulation, the simple formula of color temperature, maximum luminous flux and color index of LED module with cold and warm white light LED mixed with dual channel pulse width modulation is derived. Warm white light (color temperature 3282k) and cold white light (color temperature 12930k) are used for color mixing experiment, and the duty cycle can be adjusted by controlling pulse width by single chip microcomputer. The results show that the error between theoretical calculation and experimental value is small, which proves the accuracy of the model.

2. Multi base LED chip can improve the color index of light source, and can write a simulation software for mixed white light parameters based on color measurement method. The maximum value of the color index of the synthetic light source and the corresponding number of LED ratios can be obtained by the simulation calculation of the spectrum import program of the cold, warm white and monochrome LED measured by the experiment. The results show that the white light with temperature between 3500K and 12300k and color index Ra of 92.0 to 97.7 can be obtained by the synthesis of warm white LED and red, green and blue LED; The low temperature white light (3500k-4500k) with the color index RA between 95.0 and 97.8 can be obtained by combining with red, green and green LED. High color temperature white light (8200k-13000k) with RA between 90.9 and 98.4 can be obtained by combining cold white LED with red, green and green LED. The theoretical calculation of the number of LED ratio with the color temperature of 7803k and the color index Ra of 97.29 is made. The experimental results are 7992k, the color index RA is 97.1.

3. The wrgb-led module is studied to obtain mixed white light with wide color temperature dynamic variation and high color rendering. With the combination of warm white and red, green and blue LED, pulse width modulation drive and optimized traversal range, the LED synthetic white light with high color rendering performance and wide color temperature is obtained. According to the simulation results, the mixed white light with color temperature varying from 2572k to 12585k is obtained. The average interval of color temperature variation is 193k, and the color rendering index RA can be maintained between 93 and 96.

4. The design of interior lighting control system based on ZigBee and WiFi can be completed. The lighting control software of PC can be completed by C # language. RGB mixed light, color temperature adjustment and color index optimization algorithm are introduced to realize the basic functions of wireless control, color temperature adjustment, brightness adjustment and color change of LED lamps.