Tram Signal Coordination Control Method Based On Multi-path Optimization

As a supplement to fast rail transit such as urban subways,trams are widely used in many cities in China.At present,the coordination control of tram signals is mostly based on the main line control of a single straight-line tram.It lacks consideration of multi-path conditions such as multi-line trams and social vehicles that make turns.However,with the development of the city,various types of multi-path tram turning networks are bound to become a trend.To address the issue,the research paper is organized as follows:On the basis of on-the-spot investigation and inspection of relevant data,the vehicle characteristics such as the length and width of the tram and the maneuverability parameters such as driving speed,acceleration,deceleration and stopping time are calibrated.Then,we analyze the section form,site layout and road of the tram.Operational characteristics such as power allocation,and analysis of the parameters required in the model for the fast charging and continuous power supply of the site,lays the foundation for the construction of the subsequent green wave model.For the tramway turn intersection,we analyze the traffic organization and driving characteristics of the single-line and multi-line trams through the intersection,and study the different cross-section signals of the trams for the common phase of the tram and the conventional ground traffic.We design the optimal phase scheme for a single intersection and a set of signal timing procedures considering the influence of phase sequence which is suitable for single-point intersections in the state of tram laying.Based on the method of signal timing of intersections under the condition of tram laying,the multi-path trunk green wave model is designed based on MAXBAND model,which is combined with the driving characteristics of social vehicles and the driving characteristics of trams.The model can coordinate the green light time,phase difference and left turn phase sequence of each intersection of the main line.Under the same signal control condition,the green wave of the social vehicle and the green wave of the multi-path tram will be generated respectively.In addition,the traffic of the tram and the social vehicle will be taken into consideration to reduce the delay time and number of stops at the intersection.The optimization goal of the model is that the social vehicle green wave bandwidth is the largest under the premise of meeting the traffic demand of the tram.Then,considering the coordination of the green wave model under induction control,we propose the coordination strategy of the intersection signal scheme under the active priority of the multi-track tram,and designing an active priority control process for the tram.To verify the feasibility of the model,we choose the Nanjing Kirin typical tram turning line to study and use the signal multi-path green wave model to optimize the signal phase sequence,timing and phase difference of each intersection.Then,we obtain the green wave system including the tram,time and space map.With the help of VISSIM simulation software,the current conditions,multi-path trunk green wave,multi-path trunk green wave plus active priority control of trams and social vehicles are simulated.The road operation efficiency under such scheme is evaluated using metrics including delay,number of stops,queue length,etc.The results show that the trunk multi-path green wave model can effectively improve the traffic efficiency of social vehicles and trams operation,and the initiative priority can guarantee the minimum parking delay of trams at the cost of affecting social vehicles.