Study On Energy-Saving Technology Of Highway Tunnel Lighting System

Nowadays with the rapid development of economy and society in China, Tunnels bring great convenience for highway traffic. A better visual environment for vehicle drivers should be provided in tunnels in order to ensure driving safety. Tunnel lighting facilities play a key role to provide a good visual environment for vehicle drivers in tunnels to ensure driving safety. Because of the visual adaptation problems when vehicle drivers enter and exit the hightway tunnel, how to ensure vehicles to access and pass the tunnels safely during the day and night with design speed has become a primary concern problem. Tunnel lighting is also the greatest energy consumption unit in tunnels. On the premise of security, how to optimize design for tunnel lighting system and reduce energy consumption to the most extent and save operation cost has important realistic significance. In view of the problems of excessive energy consumption of tunnel lighting at present, in the paper, tunnel lighting system was studied from four aspects of light source characteristics, luminaires distribution, light distribution methods and lighting control schemes.By comparing the performances of light sources, the adaptabilities of light sources in tunnel were analyzed. Simulation experiments were made by lighting design software DIAlux for HPS (high pressure sodium) and LED, results show that LED had higher lighting efficiency, greater energy-saving and better color rendering in key areas of the tunnel than HPS. The new mesopic theory was applied to tunnel lighting, which not only improved road surface lighting quality, but also reaalized energy-saving in a certain extent.Three luminaires distribution methods were studied, including symmetrical distribution, interleaving distribution and central distribution, results showed that the lighting efficiency of the central luminaires distribution was the highest, and the interleaving luminaires distribution was better than the symmetrical luminaires distribution. If the central luminaires distribution method were adoped in the advisable tunnel, it could improve lighting efficiency and saved light source power. Mathematical models of the single lamp lighting and the above three luminaires distribution methods were established, and optimal design were made.for them. Simulation experiments were made with lighting software DIAlux for transverse symmetrical lighting, longitudinal symmetrical and counter beam lighting, results showed that the counter beam lighting was more reasonable to be adopted in the tunnel entrance zone, the lighting efficiency could be improved and the energy consumption could be saved. Compared with the other two light distribution methods, longitudinal symmetrical lighting had higher road surface uniformity and was conducive to the large luminaries spacing in the tunnel internal zone, power consumption could be reduced by decreasing the number of luminaries used. The effect factors of counter beam lighting were studied.Two control schemes of tunnel lighting system based on fuzzy theory and stepless dimming were proposed and designed, and the corresponding control models were established and the control programs flow were designed, the lighting effect of the above two control schemes and four hierarchical control were compared by simulated tunnel internal and external environment, results showed that the energy-saving effect of stepless dimming control scheme was the best, and fuzzy dimming control scheme was better than four hierarchical dimming control scheme.