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Railway vehicle speed control in a mountainous track
Published in Maksym Spiryagin, Timothy Gordon, Colin Cole, Tim McSweeney, The Dynamics of Vehicles on Roads and Tracks, 2018
H. Magalhães, J. Ambrosio, J. Pombo
The vehicle speed is controlled by the traction wheelsets. These wheelsets are subjected to axial moments developed by the powertrain and braking systems of the vehicle. The acceleration or deceleration of the traction wheelsets is transmitted to the whole vehicle through the suspension system. The powertrain consists of the engine and the gear elements that impose the rotational motion of the traction wheelsets, such as, transmission shaft and axle gear. The powertrain is responsible for the acceleration of the vehicle by converting the electric energy, in the case of electric trains, into kinetic energy. In turn, dedicated braking systems exists in the vehicle for the decelerations (Grote & Antonsson 2009). Figure 2 (a) shows a schematic representation of a bogie that contains two traction wheelsets that are controlled by a common engine and brake devices.
Analysis of energy chains
Published in Kornelis Blok, Evert Nieuwlaar, Introduction to Energy Analysis, 2020
Kornelis Blok, Evert Nieuwlaar
Another example of energy chain analysis is the analysis of the energy performance of automotive transportation. The term well-to-wheels (WTW) analysis is often used in this context. Options for automotive transportation can be subdivided into the fuel used (gasoline, diesel, electricity, (compressed) natural gas, biofuels etc.) and the powertrain that is implemented in the car. A powertrain is the combination of the energy source (fuel tank, battery etc.) and the power source (energy converter like combustion engine or electric motor). The fuel part of the WTW-analysis is called well-to-tank (WTT) analysis and the powertrain part is the tank-to-wheel (TTW) analysis. Figure 8.2 shows a selection of results from European research, comparing various options for increased electrification of transport with a typical car used in the European market. The results shown are for a typical gasoline-fuelled internal combustion engine (ICE), a hybrid-electrical vehicle without external electricity supply (HEV), hybrid electric vehicles with external electricity supply (plugin hybrid electric vehicle, PHEV, and range extended electric vehicle, REEV) and a battery electric vehicle (BEV). The results show that the tank to wheel performance of an electric vehicle is much better than for the internal combustion engine. The TTW electricity requirement for the BEV is about 27 per cent of the fuel requirement of the ICE. As can be expected, the results for vehicles with external electricity supply depend strongly on the way the electricity is produced (the WTT part). Note that the results presented in Figure 8.2 do not include the energy use (and greenhouse gas emissions) for producing, maintaining and waste management of the car. Such contributions are typically analysed using life-cycle assessment, which is the topic of Chapter 9.
A bibliometric analysis and review on reinforcement learning for transportation applications
Published in Transportmetrica B: Transport Dynamics, 2023
Can Li, Lei Bai, Lina Yao, S. Travis Waller, Wei Liu
A hybrid-electric vehicle usually combines a conventional powertrain (e.g. gasoline) with an electric engine. Most existing studies dealing with energy management of HEVs follow pre-defined rules, which heavily rely on the accurate prediction of future traffic conditions and are not straightforward for applications under time-sensitive driving conditions (Qi et al. 2019). RL strategies have been effective tools to avoid the need for precise forecasts.