Optimal Energy-Efficient Operation of a Metro Train on a Long and Steep Downhill Segment

Because the standard four-stage operation and control strategy cannot fully utilize the gravitational potential energy of a train operating on a long and steep downhill segment, this paper further improves the method for train operation and control strategy. The improved operation includes three stages of acceleration, coasting-speed limit cruising, and braking. Taking the speed limit, time limit, and distance limit as the constraints, the coasting condition switching point, braking condition switching point, traction coefficient, and braking force coefficient are used as the decision variables. Then, an improved train traction energy consumption model is constructed, and an improved differential evolution algorithm is designed to solve this model. The improved method is used to simulate two long and steep downhill segments of the Nanning metro. The results show that the improved method can meet the requirements of speed limit, time limit, and distance limit. Compared with the standard four-stage operation, the improved train operation and control strategy can reduce train energy consumption by more than 40% on the two long and steep downhill segments; compared with other similar algorithms, the improved algorithm is more suitable for solving the model.