13,681 research outputs found
Smart Procurement of Naturally Generated Energy (SPONGE) for Plug-in Hybrid Electric Buses
We discuss a recently introduced ECO-driving concept known as SPONGE in the
context of Plug-in Hybrid Electric Buses (PHEB)'s.Examples are given to
illustrate the benefits of this approach to ECO-driving. Finally, distributed
algorithms to realise SPONGE are discussed, paying attention to the privacy
implications of the underlying optimisation problems.Comment: This paper is recently submitted to the IEEE Transactions on
Automation Science and Engineerin
A state-of-the-art review on torque distribution strategies aimed at enhancing energy efficiency for fully electric vehicles with independently actuated drivetrains
© 2019, Levrotto and Bella. All rights reserved. Electric vehicles are the future of private passenger transportation. However, there are still several technological barriers that hinder the large scale adoption of electric vehicles. In particular, their limited autonomy motivates studies on methods for improving the energy efficiency of electric vehicles so as to make them more attractive to the market. This paper provides a concise review on the current state-of-the-art of torque distribution strategies aimed at enhancing energy efficiency for fully electric vehicles with independently actuated drivetrains (FEVIADs). Starting from the operating principles, which include the "control allocation" problem, the peculiarities of each proposed solution are illustrated. All the existing techniques are categorized based on a selection of parameters deemed relevant to provide a comprehensive overview and understanding of the topic. Finally, future concerns and research perspectives for FEVIAD are discussed
AN ENERGY STRATEGY FOR PUBLIC TRANSPORT SYSTEMS
The paper describes the energy consumption processes in a public transport system and identifies areas where savings can be made. An assessment is undertaken of the cost of achieving energy savings, the effectiveness of those savings and a priority proposed for realising them. The paper also discusses the role of different fuels and the trends in future availability. From this proposals are made for changing fuel sourcesm, to make public transport less vulnerable to market price fluctuations
Evolution towards a Sustainable Public Transport in the City of Madrid
This chapter is a vision of the path followed by EMT of Madrid, during 25Â years, towards the sustainability, efficiency, and contribution to the air quality in the city, starting from a diesel fleet, until getting a fleet 100% of clean vehicles, mostly GNC, which is already a reality. It shows the evolution and the use, from the practical perspective of an operator, of all the technologies available at each moment (biodiesel, bioethanol, hydrogen, electricity, natural gas, hybridization, dualisation, start-stop, catalysis, etc.) in Madrid, in a fleet of more than 2000 buses, more than 200 lines, and more than 400 million passengers per year, which makes this case an international benchmark. In addition, EMT is currently at the end of the transition to gas vehicles (CNG) and the implementation of urban electric mobility from the double perspective of the mobile material and the associated infrastructure needed, an essential case study towards sustainable public transport
Future âgreenerâ urban transport: accessible, mobile and resilient cities?
Geographers, amongst others, have been considering urban futures for some time now. They all try to conceptually understand what a âsustainable cityâ in Europe / the UK / globally might look like. oncepts such as liveable, âgreenâ, sustainable and resilient are being discussed, with carbon emissions and transitions, including from transport. Mobility (or what some authors call motility) is one strand, with lifecycle assessment of vehicles and fuels being applied . This article reviews visions and policies for more resilient urban transport
Multi-objective energy management and charging strategy for electric bus fleets in cities using various ECO strategies
The paper presents use case simulations of fleets of electric buses in two cities in Europe, one with a warm Mediterranean climate and the other with a Northern European (cool temperate) climate, to compare the different climatic effects of the thermal management strategy and charging management strategy. Two bus routes are selected in each city, and the effects of their speed, elevation, and passenger profiles on the energy and thermal management strategy of vehicles are evaluated. A multi-objective optimization technique, the improved Simple Optimization technique, and a âbrute-forceâ Monte Carlo technique were employed to determine the optimal number of chargers and charging power to minimize the total cost of operation of the fleet and the impact on the grid, while ensuring that all the buses in the fleet are able to realize their trips throughout the day and keeping the battery SoC within the constraints designated by the manufacturer. A mix of four different types of buses with different battery capacities and electric motor specifications constitute the bus fleet, and the effects that they have on charging priority are evaluated. Finally, different energy management strategies, including economy (ECO) features, such as ECO-comfort, ECO-driving, and ECO-charging, and their effects on the overall optimization are investigated. The single bus results indicate that 12 m buses have a significant battery capacity, allowing for multiple trips within their designated routes, while 18 m buses only have the battery capacity to allow for one or two trips. The fleet results for Barcelona city indicate an energy requirement of 4.42 GWh per year for a fleet of 36 buses, while for Gothenburg, the energy requirement is 5 GWh per year for a fleet of 20 buses. The higher energy requirement in Gothenburg can be attributed to the higher average velocities of the bus routes in Gothenburg, compared to those of the bus routes in Barcelona city. However, applying ECO-features can reduce the energy consumption by 15% in Barcelona city and by 40% in Gothenburg. The significant reduction in Gothenburg is due to the more effective application of the ECO-driving and ECO-charging strategies. The application of ECO-charging also reduces the average grid load by more than 10%, while shifting the charging towards non-peak hours. Finally, the optimization process results in a reduction of the total fleet energy consumption of up to 30% in Barcelona city, while in Gothenburg, the total cost of ownership of the fleet is reduced by 9%
Advanced Control and Estimation Concepts, and New Hardware Topologies for Future Mobility
According to the National Research Council, the use of embedded systems throughout society could well overtake previous milestones in the information revolution. Mechatronics is the synergistic combination of electronic, mechanical engineering, controls, software and systems engineering in the design of processes and products. Mechatronic systems put âintelligenceâ into physical systems. Embedded sensors/actuators/processors are integral parts of mechatronic systems. The implementation of mechatronic systems is consistently on the rise. However, manufacturers are working hard to reduce the implementation cost of these systems while trying avoid compromising product quality. One way of addressing these conflicting objectives is through new automatic control methods, virtual sensing/estimation, and new innovative hardware topologies
Scaling Milton Keynes power requirements for electrical transportation
Milton Keynes is home to the UKâs first installation of a wirelessly charged passenger bus route. This Inductive Power Transfer (IPT) system enables a fleet of 8 electric buses to service a demanding 15-mile urban route. Opportunistic wireless charging of the batteries during the layover time at the routes allows reducing the size of the batteries, consequently improving cost and performance characteristics of the bus. This paper aims to analyze the effects of electric buses on the electricity distribution grid. In particular, the paper analyses scalability of the IPT solution to all urban routes in Milton Keynes and compares peak power requirements generated at different points in the network with typical industrial and commercial (I&C) loads
Hierarchical Control of Electric Bus Lines
In this paper, we propose a hierarchical control strategy for a line of electric buses with the double objective of minimizing energy consumption and providing regular service to the passengers. The state-space model for the buses is formulated in space rather than in time, which alleviates the need for integer decision variables to capture their behavior at bus stops. This enables us to first assemble a fully-centralized multi-objective line problem in the continuous nonlinear optimization framework. It is then reassembled into a hierarchical structure with two levels of control in order to improve on scalability and reliability. This new supervisory structure consists of a centralized line level controller which handles the time headway regularity of the buses, and of decentralized bus level controllers which simultaneously manage the energy consumption of each individual bus. Our method demonstrates good battery energy savings and regularity performances when compared to a classical holding strategy
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