Reducing metro trip times and energy consumption through speed control, holding and boarding limits

Abstract

A mathematical programming model is presented for controlling the operation of a line in a metro train system so as to minimize social cost in passenger trip times and energy consumption. The minimization is accomplished through three control strategies: speed control between stations, train holding and boarding limits. All three can be implemented individually or simultaneously. The proposed approach is evaluated by simulations demonstrating that the speed control and holding strategies alone lower social cost by up to 20% compared to uncontrolled baseline operation. Although average train speed declines slightly in the model’s solutions, the reducible portion of total trip time falls by more than 70%. The model also distributes passengers more evenly, thus improving user comfort. These results demonstrate that substantial reductions in both user trip times and energy costs can be achieved simultaneously.