Research On Key Technologies Of Tunnel Lighting Intelligent Control System Based On LED Color Temperature Adjustment

With the continuous advancement of the construction of highway tunnels,the number of tunnels and the total mileage have been continuously increasing.The tunnel lighting control system has gradually become a hot spot for relevant scholars at home and abroad.At present,the tunnel lighting control system mainly considers the relationship between human visual effect,energy saving and lighting brightness during the design process,that is,brightness adjustment has become the main standard for both safety and energy saving of the tunnel.The latest research shows that the color temperature of the light source has a certain influence on the visibility and comfort of the driver’s eyes.It is very important to use the color temperature of the light source as an indicator of the tunnel light environment to guide the design of the tunnel lighting control system.To this end,this paper introduces the concept of dynamic color temperature adjustment into the tunnel lighting system based on the LED light source,designing a tunnel lighting control system based on the dynamic adjustment of the LED color temperature,and implementing the process of dynamic adjustment of the light color around the LED light source.In-depth study of key technologies.First,the paper analyzes the characteristics of LED photochromatics and the theory of LED light mixing.Based on this,a dynamic calculation model of LED light color based on three-channel PWM dimming technology is derived,and the target color temperature and target luminous flux of mixed white light are established Function mapping relationship with the PWM duty cycle signal.Using warm white light,green light and cool white light as the three primary color experimental light sources,an experimental light source control drive system was built,and the experimental verification of the calculation model was carried out through the LED light color electrical analysis system.The experimental results show that the calculation model can better guide the LED light source to achieve three-channel PWM light color adjustment,the error of the correlated color temperature is kept within 1%,and the error of the luminous flux is kept within 3.5%,which provides a theory for the dynamic adjustment of the color temperature of the tunnel lighting stand by.Secondly,for the current sharing problem of multi-channel parallel LED light sources,a LLC current sharing resonant LED drive circuit based on capacitor capacitive reactance balance is designed.The specific current sharing principle of the drive circuit is introduced in detail.Perform modeling analysis.On this basis,the corresponding closed-loop feedback control circuit and PWM dimming circuit are designed.Next,the parameter design and selection of the main components of the main circuit,control circuit and dimming circuit were carried out.Based on MATLAB software,the overall simulation model of the drive circuit was built and the circuit simulation analysis was carried out.At the same time,a 38 W experimental prototype was made for actual Test of current sharing effect and dimming effect.The simulation and experimental results show that the designed current-sharing topology has a good current-sharing effect,which can achieve accurate PWM dimming,and provides hardware support for the LED light source to achieve dynamic adjustment of light color.Finally,a set of LED light color dynamic adjustable tunnel lighting control system based on open source platform was designed and built.According to the overall architecture of the system,the GPRS communication module,main controller,Zig Bee wireless communication module and sub-controller are specifically selected;based on Lab VIEW software,a tunnel lighting control platform with multiple functions such as control and remote communication is developed,and the Arduino is used The IDE software completes the development of the color temperature adjustment program of the lower computer.Build a system simulation experiment platform,and verify the light and color control effect of the system through simulation experiments.Simulation experiments show that the host computer can accurately output control instructions to control the LED light source to achieve dynamic adjustment of light color in different sections of the tunnel.Finally,summarize and prospect the work of this article.