Impact on railway infrastructure of wayside energy storage systems for regenerative braking management: a case study on a real Italian railway infrastructure

Abstract

Today, in the railway sector there is considerable interest in studying the best ways of exploiting train braking energy, in order to achieve a reduction in energy costs and better stabilisation of grid voltage. Among the various on-board or wayside measures proposed, one of the most promising solutions is based on using wayside energy storage systems (WESSs). A WESS is a storage installation which can be integrated into mass transit systems in urban areas as well as into long-distance railway lines. It can operate as a smart storage system able to provide relevant benefits in terms of recovering surplus regeneration braking energy, voltage stabilisation, reduction of peak power demand. For these purposes, an effective and flexible simulator is essential to provide all the elements needed to focus and compare feasible configurations and operations. This study examines the problem of introducing the WESS technology in real railway infrastructure. It proposes a method based on a simulator of the WESS system integrated into the infrastructure and carries out the results of dynamic simulations referring to real operating data of the system and vehicles. The results highlight the performance of the WESS in terms of energy and power exchange, also discussing economic aspects.

Modeling, Simulationand Analysis of On-Board Hybrid Energy Storage Systems for Railway Applications

“…Similar conclusions were obtained in [26]; in this work, the use of wayside energy storage improved the overall efficiency by more than 20% and also improved the controllability and the voltage profile of the network. Similar conclusions were obtained in [24,27] supporting the previous conclusions. In [24], the use of energy storage at the substation level reduced the annual cost of energy by 13%.…”

Non‐linear switched model for accurate voltage estimation and power flow analysis of DC railway systems

“…In such a case, on‐board ESS can offer off‐grid traction possibilities. More details about such technologies and other examples are in [5–16].…”

“…[3, 4] and improving the infrastructure. Different solutions are, therefore, envisaged such as reversible traction power substations (TPSs) [5–8], energy storage systems (ESSs) [2, 8–16], or renewable energies [16]. Optimisation techniques are also often used to improve the operation of specific subsystems (i.e.…”

“…Indeed, they represent non‐linear behaviours, which require complex models that are generally solved using numerical iterative techniques [19, 20]. Most existing and commercial tools consider the train as a static current source and use the conductance matrix iterative approach known as the current injection (CI) method [12–15, 18–20]. These currents are then injected into a modified nodal analysis (MNA) method to solve and analyse the DCTN in a specific configuration according to the injected currents [21, 22].…”

Off‐board and on‐board energy storage versus reversible substations in DC railway traction systems

“…Nowadays, there are many research lines chasing this objective. For instance, a static simulator to analyse the impact of the wayside energy storage along the network is proposed in [19]. There, the authors propose a model to study a specific scenario and evaluate the recovering surplus of regeneration braking energy, voltage stabilisation and reduction of peak power demand obtained with this technology.…”