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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Desenvolvimento e análise de estratégias de gerenciamento de potência em veículo elétrico híbrido de configuração paralela / Development and analysis of strategies of power management in hybrid electric vehicles with parallel configuration

Corrêa, Fernanda Cristina, 1984- 07 December 2013 (has links)
Orientador: Franco Giuseppe Dedini / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-23T05:45:50Z (GMT). No. of bitstreams: 1 Correa_FernandaCristina_D.pdf: 2997267 bytes, checksum: d232b968b2a0c38ad71028200424345b (MD5) Previous issue date: 2013 / Resumo: O considerável aumento de automóveis tem causado graves efeitos ao meio ambiente e para o homem, fato este que incentiva a pesquisa pela obtenção de formas de energia mais limpa. A adoção da tecnologia propulsora híbrida veicular tem contribuído para a redução da agressão causada pelos automóveis ao meio ambiente. O termo "híbrido" deriva da combinação de duas ou mais fontes de potência, sendo que a combinação mais comum se faz através de um motor de combustão interna (MCI), comumente usado em veículos convencionais, com o conjunto bateria e motor elétrico (ME) usados nos VEs (Veículos Elétricos). Em geral, a principal razão para usar a arquitetura híbrida elétrica é o grau de liberdade adicional devido à presença de uma fonte de energia adicional além do tanque de combustível; isto implica que, a cada instante, a potência necessária pelo veículo pode ser fornecida por uma dessas fontes, ou por uma combinação das duas. Escolher a combinação correta é normalmente uma tarefa complexa. Dentro desse contexto, neste trabalho é realizado o desenvolvimento e a análise das estratégias de gerenciamento de potência em um VEH a fim de minimizar o seu consumo de combustível e consequentemente suas emissões. São desenvolvidas duas estratégias de gerenciamento, a primeira baseada em regras e a segunda utilizando sistemas fuzzy. Além disso, também é realizado o controle interno do motor a combustão, de forma que este opere, na maior do tempo, em regiões que tenham um menor consumo específico. Por meio da utilização das estratégias de gerenciamento de potência aliadas ao controle do motor a combustão é possível obter uma considerável economia de combustível. Comparando-se as duas estratégias desenvolvidas, a estratégia baseada em fuzzy é a que proporcionou melhor economia de combustível / Abstract: The considerable increase of automobiles has caused serious effects to the environment and to man; this fact encourages research by obtaining forms of cleaner energy. The adoption of hybrid vehicle propulsion technology has contributed to the reduction of aggression caused by car to the environment. The term "hybrid" derives from the combination of two or more power sources, and the most common combination is by of the engine (MCI), commonly used in conventional vehicles, together with the battery and motor electric (ME) used in EVs (Electric Vehicles). In general, the main reason to use the architecture electric hybrid is the additional degree of freedom due to the presence of an energy source plus additional fuel tank, this implies that, at each instant, the power required the vehicle may be provided by one of these sources, or a combination of both. Choose the correct combination is usually a complex task. Within of this context, this work development is undertaken and analysis of strategies for power management in a VEH in order to minimize fuel consumption and thus emissions. Two management strategies are developed, the first is based in rules and the second is based in fuzzy systems. Furthermore, it is also performed internal control engine combustion of so that it operates at greater time in regions having lower specific fuel consumption. Through the use of power management strategies coupled with the motor control combustion is possible to obtain a considerable saving of fuel. Comparing the two strategies developed, the strategy based on fuzzy is that provided better economy fuel / Doutorado / Mecanica dos Sólidos e Projeto Mecanico / Doutora em Engenharia Mecânica
262

Development and evaluation of a range anxiety-reducing business model for connected full electric vehicles

Kammerer, Sven Daniel 27 September 2012 (has links)
Submitted by Eliene Soares da Silva (eliene.silva@fgv.br) on 2012-11-26T14:59:25Z No. of bitstreams: 1 FINAL THESIS_Sven Kämmerer.pdf: 4409442 bytes, checksum: f0b4d51fcb5997ef130c873c65386e15 (MD5) / Approved for entry into archive by Eliene Soares da Silva (eliene.silva@fgv.br) on 2012-11-26T15:03:02Z (GMT) No. of bitstreams: 1 FINAL THESIS_Sven Kämmerer.pdf: 4409442 bytes, checksum: f0b4d51fcb5997ef130c873c65386e15 (MD5) / Made available in DSpace on 2012-11-26T15:16:15Z (GMT). No. of bitstreams: 1 FINAL THESIS_Sven Kämmerer.pdf: 4409442 bytes, checksum: f0b4d51fcb5997ef130c873c65386e15 (MD5) Previous issue date: 2012-09-27 / This thesis develops and evaluates a business model for connected full electric vehicles (FEV) for the European market. Despite a promoting political environment, various barriers have thus far prevented the FEV from becoming a mass-market vehicle. Besides cost, the most noteworthy of these barriers is represented by range anxiety, a product of FEVs’ limited range, lacking availability of charging infrastructure, and long recharging times. Connected FEVs, which maintain a constant connection to the surrounding infrastructure, appear to be a promising element to overcome drivers’ range anxiety. Yet their successful application requires a well functioning FEV ecosystem which can only be created through the collaboration of various stakeholders such as original equipment manufacturers (OEM), first tier suppliers (FTS), charging infrastructure and service providers (CISP), utilities, communication enablers, and governments. This thesis explores and evaluates how a business model, jointly created by these stakeholders, could look like, i.e. how stakeholders could collaborate in the design of products, services, infrastructure, and advanced mobility management, to meet drivers with a sensible value proposition that is at least equivalent to that of internal combustion engine (ICE) cars. It suggests that this value proposition will be an end-2-end package provided by CISPs or OEMs that comprises mobility packages (incl. pay per mile plans, battery leasing, charging and battery swapping (BS) infrastructure) and FEVs equipped with an on-board unit (OBU) combined with additional services targeted at range anxiety reduction. From a theoretical point of view the thesis answers the question which business model framework is suitable for the development of a holistic, i.e. all stakeholder-comprising business model for connected FEVs and defines such a business model. In doing so the thesis provides the first comprehensive business model related research findings on connected FEVs, as prior works focused on the much less complex scenario featuring only 'offline' FEVs.
263

A control strategy for the power system of a hybrid vehicle

Furrutter, Marco Klaus 24 October 2012 (has links)
M.Ing. / The increase in awareness of the environmental problems resulting from emissions released from vehicles have forced governments and car manufactures to invest more time in to the designing a vehicle that is an alternative to petrol driven vehicles. This dissertation aims to introduce a control strategy to manage the flow of energy of different power sources that may be found on a vehicle. Hybrid vehicles are a possible solution to reducing carbon emissions that play a part in global warming. In this dissertation, di erent hybrid vehicles are de ned and their components discussed in detail. The possibility of more than one energy source to power the vehicle introduces more exibility in terms of the drivetrain but this increases the complexity of the energy control management. The goal is to optimize the energy control management to reduce fuel consumption and therefore reduce emissions. Operating procedures for the various hybrid con gurations are discussed. Simulations of the Energy Management System of the hybrid electric vehicle are used to develop the control optimization algorithm. Various control optimization procedures are discussed. Satisfactory results from the simulations allow the implementation of the hybrid onto a platform entered into the South African Solar Challenge 2010, which covered a distance of 4000 km. The Energy Management system selected for the parallel hybrid electric vehicle demonstrated fuel savings, which meant a reduction in emissions, which is the goal of any hybrid vehicle. Further investigations include more intelligent controllers to adjust the parameters of the energy management controller to allow for adaptation to various driving conditions, e.g. urban and motorway driving.
264

Analysis of fuel consumption reduction potential through the use of an electrically driven air conditioning compressor

Marais, Charel January 2007 (has links)
The disturbing current situation regarding the world climate has initiated a major wave of urgent developments towards decreasing the overall impact of human activities on the living environment. A major role player in this development is the automobile industry that is inherently connected to pollution of various types, be it air, water or noise pollution. There have been drastic changes not only in the technologies employed in producing vehicles and components, but also in the construction and technologies built into modern automobiles to lessen the overall environmental impact of the industry. Noxious emissions have been decreased, overall efficiencies increased and vehicles are becoming more economical with each new generation. Stricter laws dictate that the level of acceptable vehicle emissions is to be decreased ever further and all manufacturers are developing various possibilities to achieve this. With the emergence of hybrid vehicle technology, there was also a sudden development of different electrical systems that were made viable by the higher onboard voltage systems employed in hybrid vehicles. One of these developments was the electrical air conditioning compressor for use in automobile applications. Although it is designed to operate with a higher voltage than the traditional 12V onboard vehicle systems, it is theoretically possible to incorporate it into a 12V system by making use of a DC-DC converter to step up the supply voltage of the electrical compressor sufficiently to allow for its successful operation. The question therefore arises whether it would be feasible and sensible to employ an electrical air conditioning system in conventional combustion engine vehicles from an overall fuel consumption and vehicle emissions point of view. A modelling approach was taken where an overall vehicle driving simulation was created to represent an average modern production vehicle. The simulation was then extended to include the options of incorporating models for both mechanically and electrically driven air conditioning systems. This provides insight into the influences of the air conditioning system on the vehicle’s overall fuel consumption and an opportunity to compare the influences from the two different systems. This study attempted to provide answers to some of the viability questions regarding the incorporation of electrically driven air conditioning systems into vehicles that use standard 12V onboard voltage systems. It was found that the electrical system has definite potential as a viable replacement option for the conventional system should it be combined with an appropriate alternator and equipped with an efficient control system.
265

Driving electric ? : a financial assessment of electric vehicle policies in France / Une évaluation financière des politiques publiques en faveur des véhicules électriques en France

Windisch, Elisabeth 25 June 2013 (has links)
Au cours des années récentes, les véhicules électriques sont revenus sur le devant de la scène des politiques publiques en matière de transport. Considérés comme un remède possible à diverses préoccupations pressantes des pouvoirs publics, ils bénéficient d'un soutien croissant de leur part. De telles mesures de soutien demeurent contestées : en effet, leur impact sur le décollage effectif des ventes, leur soutenabilité, leur utilité et leur justification sont loin d'aller de soi. Cette étude vise à éclairer l'impact des politiques publiques destinées à influencer la demande sur i) le taux de pénétration des véhicules électriques auprès des ménages français, et ii) les finances publiques. Dans un premier temps sera brossé le tableau du contexte dans lequel les véhicules électriques ont vocation à se développer. Il sera proposé un panorama large des opportunités potentielles offertes par l'introduction des véhicules électriques. Une revue internationale des politiques publiques est conduite, qui décrit les leviers de politique publique qui sont aujourd'hui actionnés en soutien au véhicule électrique de par le monde. L'accent y est mis sur les mesures destinées à agir sur la demande. Des conclusions préliminaires seront proposées sur l'efficacité de ces mesures au regard des taux observés de pénétration du véhicule électrique. Dans un deuxième temps, l'étude s'attache à évaluer le marché potentiel des véhicules électriques auprès des ménages français. L'analyse porte non seulement sur les déterminants financiers de la demande, mais aussi sur les obstacles socio-économiques à l'adoption des véhicules électriques par ces ménages. S'appuyant sur une analyse par scénarios qui permet de rendre compte des nombreuses incertitudes relatives aux évolutions à prévoir des véhicules, des coûts et des tendances de marché, une prévision du potentiel de demande à l'horizon 2023 est avancée. L'approche désagrégée qui est appliquée à partir de la base de données de l'Enquête Nationale Transports et Déplacements 2007/2008 permet d'identifier les combinaisons de instruments financiers de politique publique les plus à même de garantir certains niveaux de pénétration du véhicule électrique dans la prochaine décennie. Enfin, l'impact sur les finances publiques du remplacement d'un véhicule conventionnel par un véhicule électrique est étudié. L'analyse porte à la fois sur les phases de production et d'usage du véhicule. Le modèle d'évaluation développé à cet effet tient compte des impacts directs et indirects sur les finances publiques. Sont pris en compte les subventions directes à l'achat, les allègements fiscaux, les recettes fiscales, ainsi que les effets sur l'emploi. Les conclusions et observations tirées de l'étude permettent de formuler diverses suggestions à l'attention des constructeurs automobiles et des décideurs publics affichant la volonté de soutenir l'essor du véhicule électrique / In recent years, electric vehicles have come to the forefront of public transport policies. They are seen as remedy for various pressing public concerns and are thus increasingly benefiting from supportive policy measures. Such measures remain contested: their impact on actual vehicle uptake rates, their sustainability, usefulness and justification are far from being self-evident. This study aims at uncovering the effect of financial demand-side public policy measures on i) the uptake rate of electric vehicles among private households in France, and ii) the public budget. First, the context within which electric vehicles are to evolve is sketched. A comprehensive overview of the potential opportunities that come with the introduction of electric vehicles is given. An international policy review depicts public policy levers that are currently deployed in order to support the uptake of electric vehicles. A focus is put on financial demand-side measures. Preliminary conclusions on their effectiveness with regards to observed electric vehicle uptake rates in the various countries reviewed are drawn. Next, the potential market for electric vehicles among French households is explored. Besides financial aspects, socio-economic obstacles to electric vehicle uptake among private households are analysed. With the aid of scenario analysis that accounts for the many uncertainties with regards to future vehicle developments, costs and market trends, a forecast of the electric vehicles' potential up until 2023 is given. The applied disaggregate approach based on the database of the French National Transport Survey 2007/2008 allows identifying the most promising sets of financial public policy measures that are likely to guarantee certain electric vehicle uptake rates over the next decade. Lastly, the effect of replacing one conventional vehicle by one electric vehicle on the public budget is investigated. Both, vehicle manufacture and use aspects are considered. The set up valuation model hereby accounts for direct and indirect financial impacts on the public budget. These comprise direct purchase subsidies, tax breaks, and tax income, as well as effects of changing employment situations that alter the amount of social contributions and unemployment benefits .The study's findings and considerations allow for various suggestions for vehicle manufacturers and policy makers willing to support the uptake of electric vehicles. These are listed in the conclusions section which also sketches directions for further research
266

Sustaining Uber: Opportunities for Electric Vehicle Integration

Wagner, David 01 January 2017 (has links)
Uber and Lyft, the “unregulated taxis” that are putting traditional taxi companies out of business, are expanding quickly and changing the landscape of urban transportation as they go. This thesis analyzes the environmental impacts of Transportation Network Companies, particularly in California, with respect to travel behavior, congestion, and fuel efficiency. The analysis suggests that fuel efficient taxis are being replaced by less fuel efficient Uber and Lyft vehicles. Linear regressions were run on data from the Clean Vehicle Rebate Project’s Electric Vehicle Consumer Survey of electric vehicle owners in California. The findings indicate that Uber drivers are more reliant upon the state rebate than the general population of electric vehicle owners in California.
267

Análise de consumo de combustível em veículo automotor hibridizado / Analysis of fuel consumption in hybridized automotive vehicle

Costa, Eduardo dos Santos, 1982- 26 August 2018 (has links)
Orientador: Franco Giuseppe Dedini / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-26T13:12:33Z (GMT). No. of bitstreams: 1 Costa_EduardodosSantos_M.pdf: 3795975 bytes, checksum: 57e8b74b69e23ca6a180dd32323f0a1e (MD5) Previous issue date: 2014 / Resumo: Veículos Elétricos Híbridos representam, atualmente, uma alternativa para a redução do consumo de combustível fóssil utilizado pelos motores de combustão interna. Este trabalho analisa, em uma plataforma de simulação computacional e em condição experimental, o consumo de combustível de um veículo automotor, antes e após a hibridização. As simulações computacionais auxiliam, através de modelos matemáticos, um maior entendimento dos fenômenos físicos relacionados com os problemas de engenharia. Um modelo computacional bem elaborado possui um elevado grau de fidelidade em relação aos sistemas reais, tornando-se assim uma poderosa ferramenta de análise. A realização de experimentos, além de permitir uma comprovação de resultados, contribui para um refinamento dos modelos simulados. A tecnologia híbrida em estudo caracteriza-se pelo acoplamento de dois motores elétricos diretamente nas rodas traseiras do veículo. Por fim, busca-se a verificação da similaridade de comportamentos e/ou investigação de possíveis divergências entre o modelo matemático desenvolvido e os experimentos realizados. Um modelo de dinâmica veicular longitudinal descrito pela literatura é implementado no software Matlab/SimulinkTM e os resultados são comparados com os experimentos realizados em um dinamômetro de chassi / Abstract: Hybrid Electric Vehicles currently represent an alternative to reducing fossil fuel consumption used by internal combustion engines. This paper analyses, in a platform of computational simulation and also in experimental condition, the vehicle fuel consumption, before and after hybridization. It checks the similarity of behaviors and/or the investigation of possible differences between the developed mathematical model and experiments performed. Computer simulations help, through mathematical models, a better understanding of physical phenomena related to engineering problems. A well elaborated computer model has a high fidelity degree with the real systems, becoming a powerful analysis tool. The experiments besides allowing a proof of results, they contribute to a refinement of the simulated models. The hybrid technology under study is characterized by the coupling of two electric motors directly to the rear vehicle wheels. A model for the vehicle longitudinal dynamics described in the literature is implemented in Matlab/SimulinkTM software and the results are compared with the experiments performed on a chassis dynamometer / Mestrado / Mecanica dos Sólidos e Projeto Mecanico / Mestre em Engenharia Mecânica
268

A Novel Location-Allocation-Routing Model for Siting Multiple Recharging Points on the Continuous Network Space

January 2020 (has links)
abstract: Due to environmental and geopolitical reasons, many countries are embracing electric vehicles (EVs) as an alternative to gasoline powered automobiles. Other alternative-fuel vehicles (AFVs) powered by compressed gas, hydrogen or biodiesel have also been tested for replacing gasoline powered vehicles. However, since the associated refueling infrastructure of AFVs is sparse and is gradually being built, the distance between recharging points (RPs) becomes a crucial prohibitive attribute in attracting drivers to use such vehicles. Optimally locating RPs will both increase demand and help in developing the refueling infrastructure. The major emphasis in this dissertation is the development of theories and associated algorithms for a new set of location problems defined on continuous network space related to siting multiple RPs for range limited vehicles. This dissertation covers three optimization problems: locating multiple RPs on a line network, locating multiple RPs on a comb tree network, and locating multiple RPs on a general tree network. For each of the three problems, finding the minimum number of RPs needed to refuel all Origin-Destination (O-D) flows is considered as the first objective. For this minimum number, the location objective is to locate this number of RPs to minimize weighted sum of the travelling distance for all O-D flows. Different exact algorithms are proposed to solve each of the three algorithms. In the first part of this dissertation, the simplest case of locating RPs on a line network is addressed. Scenarios include single one-way O-D pair, multiple one-way O-D pairs, round trips, etc. A mixed integer program with linear constraints and quartic objective function is formulated. A finite dominating set (FDS) is identified, and based on the existence of FDS, the problem is formulated as a shortest path problem. In the second part, the problem is extended to comb tree networks. Finally, the problem is extended to general tree networks. The extension to a probabilistic version of the location problem is also addressed. / Dissertation/Thesis / Doctoral Dissertation Industrial Engineering 2020
269

Eco-routing and scheduling of Connected and Autonomous Vehicles

Houshmand, Arian 19 May 2020 (has links)
Connected and Autonomous Vehicles (CAVs) benefit from both connectivity between vehicles and city infrastructures and automation of vehicles. In this respect, CAVs can improve safety and reduce traffic congestion and environmental impacts of daily commutes through making collaborative decisions. This dissertation studies how to reduce the energy consumption of vehicles and traffic congestion by making high-level routing decisions of CAVs. The first half of this dissertation considers the problem of eco-routing (finding the energy-optimal route) for Plug-In Hybrid Electric Vehicles (PHEVs) to minimize the overall energy consumption cost. Several algorithms are proposed that can simultaneously calculate an energy-optimal route (eco-route) for a PHEV and an optimal power-train control strategy over this route. The results show significant energy savings for PHEVs with a near real-time execution time for the algorithms. The second half of this dissertation tackles the problem of routing for fleets of CAVs in the presence of mixed traffic (coexistence of regular vehicles and CAVs). In this setting, all CAVs belong to the same fleet and can be routed using a centralized controller. The routing objective is to minimize a given overall fleet traveling cost (travel time or energy consumption). It is assumed that regular vehicles (non-CAVs) choose their routing decisions selfishly to minimize their traveling time. A framework is proposed that deals with the routing interaction between CAVs and regular uncontrolled vehicles under different penetration rates (fractions) of CAVs. The results suggest collaborative routing decisions of CAVs improve not only the cost of CAVs but also that of the non-CAVs. This framework is further extended to consider congestion-aware route-planning policies for Autonomous Mobility-on-Demand (AMoD) systems, whereby a fleet of autonomous vehicles provides on-demand mobility under mixed traffic conditions. A network flow model is devised to optimize the AMoD routing and rebalancing strategies in a congestion-aware fashion by accounting for the endogenous impact of AMoD flows on travel time. The results suggest that for high levels of demand, pure AMoD travel can be detrimental due to the additional traffic stemming from its rebalancing flows, while the combination of AMoD with walking or micromobility options can significantly improve the overall system performance.
270

Pedal to the Metal: Accelerating the Transition to Electric Vehicles

Larson, Nicole 01 January 2019 (has links)
This thesis explores barriers to widespread adoption of electric vehicles and proposes possible policy solutions. It analyzes main barriers including awareness, upfront cost, and range anxiety, as well as existing policy solutions, and a detailed case study examining policy differences in high adopting versus low adopting states. Awareness and eduction surrounding electric vehicles and their capabilities, financial incentives and market mechanisms for reducing costs, and charging infrastructure and efficiency improvements are examined. Conclusions were formed through interviews with various experts as a method of data collection. It was found that many existing state and local level policies could be scaled to a national level to facilitate rapid reductions in transportation emissions through electrification of the transportation sector.

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