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Nowadays, electric railway system is known as an efficient and environmentally friendly solution for transportation system. Many developing countries have been expanding their railway systems to support the growth of transport demand. Even though railway system can utilize energy efficiently, its operation still requires bulk of energy. Therefore, management of multiple energy sources is an important issue for railway planning and operation. The advent of modern railway technologies provides regenerative braking system which can recover considerable energy from brake operation. Management of regenerative energy becomes a key for enhancing railway operation. This paper presents a strategy for utilizing regenerative energy in urban railway system by adjusting train operating schedule and employing wayside energy storage system. Optimizing train schedule aims to increase the degree of regenerative energy usage and applying super capacitor as temporary energy storage will manage the surplus of regenerative energy. By integrating appropriate train scheduling and energy storage system, energy management can be more flexible and effective leading to improvement of energy-saving operation. The numerical case study of Bangkok Rapid Transit System was performed and evaluated to reflect the improvement of utilizing regenerative energy. [ABSTRACT FROM AUTHOR]

Energy-saving driving is crucial during railway operation, especially in case of disturbances that require timetable rescheduling. This paper presents a method for the dynamic onboard tuning of energy-efficient speed profiles after the real-time train rescheduling process under a fixed block signaling system for mixed traffic. Similar to the idea of connected driver advisory systems, trains constantly communicate with a central traffic management system. After the rescheduling process, this system provides recommended time corridors for the passing of block signals that depend on the predicted clearing times of the block sections. These recommendations are then used for individual energy optimization of single train runs by avoiding unnecessary braking in front of block signals and maximizing cruising distances. The method is tested and evaluated on a representative line segment of the ELVA, the Railway Signaling Lab at RWTH Aachen University under realistic conditions. Energy consumptions are compared for different prediction time horizons at which the recommendations are available to the train's onboard system. In the examined test case of two trains, the energy-consumption could be decreased by up to 53% compared to operation without any rescheduling system. Thus, the proposed method is able to reduce energy consumption significantly. • Recommended time corridors for onboard energy optimization after rescheduling. • Reduction of unnecessary speed changes and maximization of cruising distances. • No negative effects on arrival times and passenger satisfaction. • Evaluation of the method on a scale model network. [ABSTRACT FROM AUTHOR]

Interest in energy-saving railway scheduling and operations is growing because of environmental concerns. Saving energy on both the hardware and software sides is an ever-increasing interest and challenge. Railway scheduling is closely related to the energy consumption of rolling stock. Energy consumption decreases when running time is increased because running curves can include considerable coasting time. However, the running time between two adjacent stations is determined for scheduling, and this running time is adhered to very strictly in Japan. Power-limiting brakes, which use regenerative braking without mechanical braking, are very useful in energy-saving operations. However, power-limiting brakes have some drawbacks, such as slow deceleration and the difficulty of notch operation. How to use power-limiting brakes effectively on schedule remains a research problem. We propose a method for developing an energy-saving schedule based on automatic train operation (ATO), which offers exceptional control notch performance and is easier to apply to an optimised schedule than manual train operation. In the proposed method, running time distribution is optimised based on energy savings between stations by keeping the total running time constant. Only the running time is optimised, so that additional timetabling strategies for energy-saving can be applied, such as reducing dwell and turnaround times and increasing running time margins. Practical considerations are included, such as determination of running times as integer values. The results of this study show that energy-saving efficiency is increased when the running time distribution between stations is optimised. [ABSTRACT FROM AUTHOR]