Energy‐efficient approach combining train speed profile and timetable optimisations for metro operations

Abstract

Rising energy cost and environment-friendly awareness make energy conservation a key issue for metro operation. Reducing traction energy consumption and improving the utilisation of regenerative braking energy are two efficient solutions to conserve energy. Two optimisation models are proposed in this study for metro systems to minimise the energy consumption by exploring energy-efficient speed profile and optimum timetable. An analytical formulation through finding suitable force coefficients and driving regime-switching points is developed to investigate the optimal speed profile of a single train during its movement along complex rail tracks considering gradients, curves, tunnels and speed limits. Moreover, the synchronisation of accelerating and braking trains is much necessarily implemented when a timetable optimisation model is established for the energy-efficient operation by adjusting the dwell times, running times and turnaround times of multiple trains. A combined particle swarm optimisation and genetic algorithm are addressed to solve the model. The case studies from the actual data of a Beijing Metro line are carried out to verify the feasibility and availability of the proposed approach. Their results show that the net energy consumption of trains along the metro line is reduced by 10.99% by combining the optimal speed profiles and timetable. force coefficient of the jth non-coasting regime in section n, n≠N, 2N TR n turnaround time at terminal n (s), n = 1, N T n running time in section n (s), n≠N, 2N D n dwell time at station n (s), n≠1, N, N + 1, 2N

Reducing Power Peaks in Railway Traffic Flow Subject to Random Effects

“…We refer to the review by Scheepmaker et al (2017) for further literature on both the energyefficient train control and the energy-efficient train timetabling. Some works attempted to combine these two problems by embedding train control between pairs of stations as a subproblem into a timetable optimization framework (Yang et al 2015, Ran et al 2020. Although our work also considers a system of interacting trains, the problem we tackle is quite different than timetabling as we focus on a string of trains running in a corridor; hence, we are not concerned with setting departure and arrival times.…”

Optimization approach to the aircraft weight and balance problem with the centre of gravity envelope constraints

“…The first focuses on methods for the construction of shipping plans to select a fleet of aircraft for a given set of cargo items, which requires transportation within a specified time window, and assigns cargo items to allowable onboard positions. Keys works considering this approach include Ng [5], Baker et al [6], Guéret et al [7], Zhang and Zhong [8], Roesener and Barnes [9] and Ran et al [10]. The second explore methods of assigning and positioning a set of cargo items into different containers.…”

“…[7], Zhang and Zhong [8], Roesener and Barnes [9] and Ran et al. [10]. The second explore methods of assigning and positioning a set of cargo items into different containers.…”

Two‐objective train operation optimization based on eco‐driving and timetabling

“…Combing eco-driving technologies with EETT, Su et al designed a model based on precise energy consumption calculations and precise speed optimization [28]. Similar research has gradually become a hot spot [29,30]. Combining the energy consumption target with the passenger waiting time target, Sun et al accurately calculate passenger waiting time based on smart card data.…”