Coordinated Passenger Flow Control Optimization On An Over-saturated Metro Line

With the continuous development of China's urban rail transit industry,more and more cities have entered the period of networked operation.The contradiction between early planning and current operation and the imbalance of the temporal and spatial characteristics of passenger flows have caused the impact of large passenger flows on the urban rail transportation system.Line capacity is approaching the limit during peak hours,and operational safety and passenger travel efficiency are difficult to guarantee.Based on the supersaturated state of the line,this paper studies the station classification,adjusts the train operation plan according to the characteristics of the station passenger flow,and studies the coordinated current limit optimization strategy of the line system.It mainly includes the following:Starting from the contradiction between supply and demand of passenger flow in urban rail transit,this paper analyzes the characteristics of passenger flow demand in terms of passenger travel influencing factors and the uneven distribution of time and space.Based on the system supply capacity of the network topology,station capacity and train transportation capacity,analyze the causes of the contradiction between supply and demand.Based on the passenger flow control related theories,an urban rail transit system platform composed of three modules of passengers,stations and trains is proposed.The basis and key of the current-limiting work are analyzed.The stations are constructed,and the station grading evaluation index system is proposed.Station rating evaluation method.An optimized model of coordinated current limit for urban rail transit and saturated lines was constructed,combined with the idea of inter-station collaboration and stationvehicle collaboration,with the goal of minimizing the total delay of passenger travel and maximizing the total number of people boarding,and using the number of passengers at the station as a decision variable The constraints are divided into four aspects: train running process,passenger arrival,passenger boarding and disembarking,and system constraints.A model solving algorithm based on TOPSIS(Technique for Order Preference by Similarity to an Ideal Solution)is designed to calculate the solution of each single objective problem.The relative distance between the result and the ideal solution to determine the optimal solution for multi-objective optimization.Taking Shanghai Metro Line 9 as a case study,the passenger flow data input model for the morning peak 7: 30-9: 00 in the Qibao-Xujiahui section of the upward direction was selected and solved using MATLAB software.The output results showed that the total delay of passenger travel was reduced.The total number of people getting on the bus has increased,verifying the effectiveness and efficiency of the model and algorithm.