Research on the Optimal Coupling and Uncoupling Position Decision of Flexible Marshalling of Urban Rail Transit

The expanding scale of the rail network presents vital challenges to urban transportation operation. The demand for energy savings and improved service levels is increasing. Flexible marshalling on spatial lines can achieve a win-win situation for both operation level and passenger service. In this paper, we construct a comprehensive objective model for selecting the optimal coupling and uncoupling positions of trains under imbalanced spatial passenger flow. The model minimizes both the traction energy cost and passenger congestion penalty cost with a genetic algorithm to determine the optimal coupling and uncoupling position of trains under different operating frequencies, focusing on the entire section of the line, considering constraints such as line conditions and capacity, decision variables as the marshalling position. The optimal solution can reduce the traction energy cost by 20.08% to 27.13% and the passenger penalty congestion cost by 14.97% to 34.99%.