Research On Intelligent Lighting Technology Of Expressway Tunnel Using LED

It is an important guarantee to make tunnel lighting environmental reason for the security of tunnel traffic.With more and more tunnels are built and put into operation in china,the tunnel traffic accidents occur frequently and power consumption is high,which caused by the limitations of lighting technology,while the contradiction between the traffic safety and comfort and energy-saving is not solved under the situation of existing lighting technology.“k value method” was adopted to calculate the tunnel brightness in the current rules in China,the method of lighting in which can't change with the traffic volume and outside brightness and ignore the visual demand of the driver in actual operation.What's more,the method of lighting all the time can't meet the development of “energy-saving+intelligent” lighting technology requirements.Therefore,it is important in both theory and practice to study on the intelligent lighting technology of highway tunnel.Tunnel lighting quality evaluation system is built considering double factors of tunnel lighting and driver.Evaluating the rationality of lighting environment from average brightness of road pavement,brightness of the total road pavement evenness,pavement evenness and longitudinal midline brightness flicker frequency and inductive requirement;The visual problem of driver through tunnel is analyzed.Pupil area change rate and reaction time is chosen to characterize driving safety and comfort of tunnel in the introduction of driver's visual characteristics evaluation index.The luminance,speed,traffic flow and human visual system parameters were obtained by illuminometer and eye tracker.The results of each parameter test are mostly analyzed,and the quality of tunnel illumination is checked by the results of the survey.After analyzing lighting effect of the subjects,a regression model of brightness reduction coefficient,speed and visual characteristics of indicators is established,and the dynamic threshold interval is determined based on the safety and comfort of drivers.The regression model of parking in tunnel was optimized to calculate the layout distance of vehicle detector.According to the position of the vehicle real-time,intelligent lighting mode of “the light on when the vehicle comes and of when leave” is realized through adjust the correction in front of the vehicle lighting area length.“XiaoSanChaKou tunnel” is taken as an example to check energy conservation,which shows the half tunnel in the calculation 24 h days saving about 20%.Finally,the LED intelligent lighting dimming control strategy is designed.The control module is divided into input unit,control decision unit and output unit,all of which cooperate to realize the real-time dimming of tunnel lighting.