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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.
541

Optimised space vector modulation for variable speed drives / MLI vectorielle optimisée pour les variateurs de vitesse

Khan, Hamid 06 November 2012 (has links)
Le travail effectué au cours de cette thèse consiste à étudier et développer des techniques innovantes de modulation de largeurs d'impulsions (MLI) qui visent à optimiser les chaînes de traction électriques embarquées dans des véhicules hybrides ou électriques. La MLI joue un rôle stratégique au coeur des variateurs de vitesse, elle influe sur le comportement général de la chaîne de traction et sur sa performance. La MLI présente des degrés de liberté qui peuvent contribuer avantageusement à redimensionner les composants du variateur tels que le circuit de refroidissement, le filtre EMI et le condensateur du bus continu. Les véhicules hybrides constituent une étape naturelle dans la transition énergétique entre les véhicules thermiques et les véhicules électriques. Notre étude contribue à l'optimisation des variateurs de vitesse en général et ceux au coeur des véhicules hybrides ou électriques en particulier. Notre apport consiste à proposer une MLI performante afin de rendre le variateur plus léger et plus compacte tout en garantissant les fonctionnalités traditionnelles. La compétitivité de ces variateurs et par conséquent des véhicules hybrides ou électriques devient alors accessible. Les véhicules hybrides ou électriques utilisent généralement une machine de traction à courant alternatif en raison de nombreux avantages que celle ci présente par rapport à une machine à courant continu. La source d’alimentation au bord d'un véhicule est une batterie, il est donc nécessaire d'utiliser un onduleur pour transformer la tension continue en tension alternative à amplitude et fréquence variables. Le contrôle de cet onduleur est réalisé par des techniques de modulation de largeurs d'impulsions (MLI) ce qui permet ainsi de réguler le couple de la machine. Les techniques MLI produisent une composante basse fréquence, le fondamental qui est le signal désiré et des composantes hautes fréquences appelées harmoniques de commutation qui sont indésirables. Dans les véhicules modernes, il y a de plus en plus de charges mécaniques pilotées par des machines électriques et des systèmes électroniques. Il est impératif d'éliminer le risque d'interférences électromagnétiques entre ces différents systèmes pour éviter le dysfonctionnement ou la défaillance. Il faut donc filtrer ces harmoniques indésirables pour qu'elles ne perturbent pas les calculateurs et autres circuits électroniques de faibles niveaux de tensions. Il existe des techniques de modulation aléatoire (RPWM) qui permettent d'étaler les harmoniques à la fréquence de commutation et ses multiples. Dans cette étude, notre choix s’est porté sur la technique de modulation vectorielle aléatoire (RSVM) qui présente plusieurs avantages par rapport à la MLI intersective. Les machines pilotées par une MLI produisent des tensions de mode commun dites « shaft voltage », qui peuvent provoquer des courants à travers les roulements de la machine, ces derniers pouvant être destructifs. Nous avons pu développer une technique MLI vectorielle basée sur un choix judicieux des vecteurs nuls pour réduire cette tension de mode commun. La chaleur produite par les pertes dans les convertisseurs à commutation dure lors de l'ouverture et de la fermeture des interrupteurs doit être évacuée rapidement, ce qui réduit le stress thermique, évite la défaillance et augmente la durée de vie des interrupteurs. Une technique utilisée pour réduire ces pertes par commutation est la modulation discontinue (DPWM) ; une amélioration est apportée à cette technique dans ce travail. Cette amélioration est présentée sous forme d'une technique discontinue évolutive (EDSVM) qui s'adapte au régime du moteur pour minimiser les pertes. Grâce à cette technique une meilleure distribution du stress thermique sur les différents bras de l'onduleur est rendue possible et permet ainsi d'augmenter la durée de vie de l'onduleur. (...) / The dissertation documents research work carried out on Pulse Width Modulation (PWM) strategies for hard switched Voltage Source Inverters (VSI) for variable speed electric drives. This research is aimed at Hybrid Electric Vehicles (HEV). PWM is at the heart of all variable speed electric drives; they have a huge influence on the overall performance of the system and may also help eventually give us an extra degree of freedom in the possibility to rethink the inverter design including the re-dimensioning of the inverter components.HEVs tend to cost more than conventional internal combustion engine (ICE) vehicles as they have to incorporate two traction systems, which is the major discouraging factor for consumers and in turn for manufacturers. The two traction system increases the maintenance cost of the car as well. In addition the electric drives not only cost extra money but space too, which is already scarce with an ICE under the hood. An all-electric car is not yet a viable idea as the batteries have very low energy density compared with petrol or diesel and take considerable time to charge. One solution could be to use bigger battery packs but these add substantially to the price and weight of the vehicle and are not economically viable. To avoid raising the cost of such vehicles to unreasonably high amounts, autonomy has to be compromised. However hybrid vehicles are an important step forward in the transition toward all-electric cars while research on better batteries evolves. The objective of this research is to make electric drives suitable for HEVs i.e. lighter, more compact and more efficient -- requiring less maintenance and eventually at lower cost so that the advantages, such as low emissions and better fuel efficiency, would out-weigh a little extra cost for these cars. The electrical energy source in a vehicle is a battery, a DC Voltage source, and the traction motor is generally an AC motor owing to the various advantages it offers over a DC motor. Hence the need for a VSI, which is used to transform the DC voltage into AC voltage of desired amplitude and frequency. Pulse width modulation techniques are used to control VSI to ensure that the required/calculated voltage is fed to the machine, to produce the desired torque/speed. PWM techniques are essentially open loop systems where no feedback is used and the instantaneous values differ from the required voltage, however the same average values are obtained. Pulse width modulated techniques produce a low frequency signal (desired average value of the switched voltage) also called the fundamental component, along with unwanted high frequency harmonics linked to the carrier signal frequency or the PWM period. In modern cars we see more and more mechanical loads driven by electricity through digital processors. It is very important to eliminate the risk of electromagnetic interference between these systems to avoid failure or malfunction. Hence these unwanted harmonics have to be filtered so that they do not affect the electronic control unit or other susceptible components placed in the vicinity. Randomised modulation techniques (RPWM) are used to dither these harmonics at the switching frequency and its multiple. In this thesis a random modulator based on space vector modulation is presented which has additional advantages of SVM. Another EMI problem linked to PWM techniques is that they produce common mode voltages in the load. For electric machines, common mode voltage produces shaft voltage which in turn provokes dielectric stress on the motor bearings, its lubricant and hence the possibility of generating bearing currents in the machine that can be fatal for the machine. To reduce the common mode voltage a space vector modulation strategy is developed based on intelligent placement of zero vectors. (...)
542

Energieprädiktion und Reichweitendarstellung durch Navigationsdaten im Kraftfahrzeug

Lamprecht, Andreas 18 November 2016 (has links) (PDF)
Im Zuge der immer größer werdenden Knappheit fossiler Ressourcen und des damit verbundenen Anstiegs des Rohölpreises ergibt sich ein Trend hin zur Elektromobilität. In den nächsten Jahren werden jedoch nur Elektrofahrzeuge mit deutlich eingeschränkter maximaler Reichweite im Vergleich zu Benzin- oder Dieselfahrzeugen produziert werden können. Um den täglichen Umgang des Kunden mit einem Elektrofahrzeug trotzdem möglichst reibungslos zu ermöglichen, wurde im Rahmen dieser Arbeit eine neuartige Anzeige der verbleibenden Reichweite auf der Navigationskarte entwickelt. Nach detaillierter Analyse vorhandener Ansätze wurde je ein empirisches und ein modellbasiertes Verfahren ausgearbeitet. Die Ansätze wurden systematisch verglichen und zu einem komplett neuartigen, hybriden Ansatz kombiniert. Die auftretenden Verbräuche des Fahrzeugs werden im Kundenbetrieb erfasst, je nach Fahrsituation klassifiziert und für eine Extrapolation in der Zukunft verwendet. Die entwickelte Methodik zur Untersuchung der erreichbaren Genauigkeit ergab ein erzielbares Fehlermaß von durchschnittlich unter 10%. / Due to the prospect of a worldwide shortage of fossil fuels and the correlated increase of prices for crude-oil, a global trend to invest in electric mobility has started. During the next couple of years, electric vehicles will still have restrictions on the maximum distance that can be driven before having the need to recharge the battery. The potential costumers face the so-called „range-anxiety“, the fear to be stranded prior to reaching the destination. In order to provide a safe and easy way of operating such a vehicle, the work conducted in the course of this doctoral thesis led to a new way of displaying the remaining range of the vehicle on a navigation map. After detailed analysis of the state of the art, an empirical- and a model-based solution for calculating the remaining range were developed utilizing predictive map-data from a roadnetwork. After a systematical optimization of the developed solutions, an embedded prototype was developed which captured the driving situation of the vehicle together with the corresponding energy-consumption in order to provide a context-aware interpolation of the remaining range, depending on where the costumer would drive next. A developed methodology of objectively determining the error produced by the system resulted in a mean-deviation of 10% of absolute value.
543

Preference veřejnosti pro politiky a změny ve vztahu k životnímu prostředí / Public Preferences for Environmental Policies and Behavioural Changes

Zvěřinová, Iva January 2019 (has links)
Iva Zvěřinová PhD Thesis Public Preferences for Environmental Policies and Behavioural Changes Abstract Environmental problems, such as climate change, are generally perceived as serious issues by the public in European countries. However, people tend to assign them a low policy priority and disagree with the introduction of some policy instruments, such as carbon tax. Few people also behave in an environmentally friendly way and reduce greenhouse gas emissions. What are the preferences of the inhabitants of several European countries regarding climate mitigation policies and behavioural changes? What makes these policies more acceptable for the public? Would people from these countries be willing to accept climate mitigation policies or behaviour, and if so, under what conditions? This thesis aims to answer these questions by applying a theoretical framework that integrates attitudes and perceptions with preferences. In the empirical part of the thesis, we analyse data from several questionnaire surveys on public responses to climate policies and climate-related behaviours in several European countries. The thesis contains four empirical studies focusing on: i. public preferences for climate mitigation policies; ii. public preferences for policy instruments to reduce GHG emissions; iii. consumers'...
544

Analyse d’une architecture de puissance dédiée aux modes traction–recharge dans un véhicule électrique. Optimisation de la commande et fonctionnement en mode dégradé / Analysis of power electronic architecture intended for drive–recharging modes in electric vehicle. Optimization of control and degraded mode operation

Kolli, Abdelfatah 11 December 2013 (has links)
La problématique de recherche abordée dans ce mémoire de thèse découle de l’étude approfondie d’une association convertisseur-machine dédiée aux modes traction et recharge d’un véhicule électrique. Il s’agit d’un onduleur triphasé constitué de trois onduleurs monophasés connectés à une machine triphasée à phases indépendantes.Dans le chapitre II, une étude comparative entre deux solutions industrielles montre que l’architecture étudiée offre des caractéristiques compétitives notamment en termes de rendement global du convertisseur, performances mécaniques, et surface de silicium nécessaire.Par ailleurs, outre la possibilité de mutualiser les trois fonctions du véhicule que sont la traction, la recharge (rapide ou lente) et l’assistance du réseau électrique, cette topologie offre plusieurs atouts : des possibilités variées d’alimentation et donc un potentiel intéressant de reconfiguration en marche dégradée. La thématique abordée dans les chapitres III et IV est donc centrée sur l’optimisation des stratégies de contrôle de cette structure vis-à-vis de deux types de défauts : les imperfections intrinsèques du système d’une part et les défaillances accidentelles d’autre part.Dans un premier temps, un travail approfondi sur les méthodes de modulation de largeur d’impulsion a permis de synthétiser une stratégie offrant une faible sensibilité vis-à-vis des imperfections de la commande et de la non-linéarité du convertisseur. Dans un second temps, il a été montré qu’en cas de défaillance d’un composant à semi-conducteur, il était obligatoire de recourir à la reconfiguration matérielle de la topologie. L’architecture permettant la continuité de service a été étudiée du point de vue de sa commande. Son analyse nous a amenés à proposer une structure de contrôle basée sur des solutions automatiques simples et efficaces. Finalement, le principe du fonctionnement en marche dégradée a été étendu au fonctionnement normal dans le but d’en améliorer le rendement sur cycle. / This Ph.D. thesis focuses on a novel combination of a frequency converter and an electric machine specially dedicated to traction drive and battery recharging modes of an electric vehicle (EV). This power architecture is composed of a six legs voltage inverter connected to a three-phase open-end winding machine. Chapter II details a quantitative comparison between two industrial power architectures and concludes that the SOFRACI powertrain is a competitive solution in terms of power converter efficiency, drive mechanical performances, and required silicon area.This architecture offers the attractive possibility of combining three important functions: traction and braking, battery charging and connecting the energy storage to a smart grid. In addition, this topology offers several advantages such as various motor feeding possibilities and a high degree of reconfiguration in degraded operating mode. The third and fourth chapters of this thesis concern the optimization of control strategies with regard to two types of faults: firstly the inherent imperfections in the converter itself (non modeled non-linearity and ineffective synchronization of control values) and secondly accidental failures. In the first case, an analysis of the pulse width modulation (PWM) methods enables the creation of a PWM strategy with a very low sensitivity to PWM uncertainties and the non-linear behavior of the power converter.In the second case, in the event of a faulty semiconductor device, it is shown that a hardware reconfiguration is required to enable an emergency traction mode. The sustainability of the traction mode is then examined with respect to the control strategy. This analysis leads to an innovative control structure based on basic and easy to implement solutions. Finally, the degraded mode operation principles have been extended to normal mode operation for the purpose of enhancing the cycle efficiency.
545

O desenvolvimento da indústria de veí­culos elétricos no Brasil: o papel das polí­ticas públicas / Development of the electric vehicle industry in Brazil: the role of public policies

Silva, Marcelo Luiz Risso Rodrigues da 07 December 2018 (has links)
A presente pesquisa tem como objetivo central discutir o papel das políticas públicas no desenvolvimento da emergente indústria de veículos elétricos no Brasil, dado o potencial transformador que os mesmos podem ter no processo de renovação da indústria automotiva nacional e na redução das emissões de CO2. Nessa direção, o país tem grandes vantagens para o avanço dessa indústria localmente, aproveitando-se da tendência de crescimento do mercado mundial. A expectativa é que até 2030 estejam rodando 160 milhões de unidades pelo mundo, contra os 2 milhões existentes em 2016. Assim, este trabalho apresenta um framework com os principais componentes de Políticas Públicas, de Pesquisa, Desenvolvimento e Inovação (PD&I) das Empresas e de Características de Mercado pertinentes ao setor, a partir de adaptações do Sistema Setorial de Inovação e Produção de Malerba (2002) à realidade brasileira, com contribuições do framework setorial de Oltra e Saint Jean (2009) e do Ecossistema de Negócios de Lu et al. (2014). Durante a investigação, foram realizadas entrevistas com os mais relevantes stakeholders da indústria de veículos elétricos e analisados dados secundários que caracterizam as incipientes iniciativas e a inexpressiva contribuição das políticas públicas para o desenvolvimento deste setor industrial. Foram identificados e hierarquizados sete componentes fundamentais de políticas públicas que influenciam diretamente a indústria de veículos elétricos no Brasil. Em termos práticos, esta pesquisa busca subsidiar os stakeholders do setor para direcionar de forma mais eficiente seus esforços, visando o incremento deste setor no país. / The main objective of this research is to discuss the role of public policies on the development of the emerging electric vehicle industry in Brazil, given the transformative potential they can have in the process of renewing the Brazilian automotive industry and reducing CO2 emissions. The country has excellent comparative advantages to develop this industry locally and take advantage of the world market growth, since the expectation is that EVs fleet will grow from 2 million in 2016 to 160 million units by to 2030. Thus, this work presents a framework with the main components of Public Policies, Companies\' Research, Development and Innovation (RD&I) and Market Characteristics pertinent to the sector, based on adaptations to Brazilian reality of the Sectorial Innovation and Production System of Malerba (2002), with contributions from the sector framework of Oltra and Saint Jean (2009) and Business Ecosystem of Lu et al. (2014). During the investigation interviews were conducted with the most relevant stakeholders of the electric vehicle industry and secondary data that characterize the incipient initiatives and inexpressive contribution of public policies to the development of this industrial sector were analyzed. Seven fundamental components of public policies that directly influence the electric vehicle industry in Brazil were identified and ranked. In practical terms, the paper aims to subsidize stakeholders to target more efficiently their efforts towards the development of this industry in Brazil.
546

O desenvolvimento da indústria de veí­culos elétricos no Brasil: o papel das polí­ticas públicas / Development of the electric vehicle industry in Brazil: the role of public policies

Marcelo Luiz Risso Rodrigues da Silva 07 December 2018 (has links)
A presente pesquisa tem como objetivo central discutir o papel das políticas públicas no desenvolvimento da emergente indústria de veículos elétricos no Brasil, dado o potencial transformador que os mesmos podem ter no processo de renovação da indústria automotiva nacional e na redução das emissões de CO2. Nessa direção, o país tem grandes vantagens para o avanço dessa indústria localmente, aproveitando-se da tendência de crescimento do mercado mundial. A expectativa é que até 2030 estejam rodando 160 milhões de unidades pelo mundo, contra os 2 milhões existentes em 2016. Assim, este trabalho apresenta um framework com os principais componentes de Políticas Públicas, de Pesquisa, Desenvolvimento e Inovação (PD&I) das Empresas e de Características de Mercado pertinentes ao setor, a partir de adaptações do Sistema Setorial de Inovação e Produção de Malerba (2002) à realidade brasileira, com contribuições do framework setorial de Oltra e Saint Jean (2009) e do Ecossistema de Negócios de Lu et al. (2014). Durante a investigação, foram realizadas entrevistas com os mais relevantes stakeholders da indústria de veículos elétricos e analisados dados secundários que caracterizam as incipientes iniciativas e a inexpressiva contribuição das políticas públicas para o desenvolvimento deste setor industrial. Foram identificados e hierarquizados sete componentes fundamentais de políticas públicas que influenciam diretamente a indústria de veículos elétricos no Brasil. Em termos práticos, esta pesquisa busca subsidiar os stakeholders do setor para direcionar de forma mais eficiente seus esforços, visando o incremento deste setor no país. / The main objective of this research is to discuss the role of public policies on the development of the emerging electric vehicle industry in Brazil, given the transformative potential they can have in the process of renewing the Brazilian automotive industry and reducing CO2 emissions. The country has excellent comparative advantages to develop this industry locally and take advantage of the world market growth, since the expectation is that EVs fleet will grow from 2 million in 2016 to 160 million units by to 2030. Thus, this work presents a framework with the main components of Public Policies, Companies\' Research, Development and Innovation (RD&I) and Market Characteristics pertinent to the sector, based on adaptations to Brazilian reality of the Sectorial Innovation and Production System of Malerba (2002), with contributions from the sector framework of Oltra and Saint Jean (2009) and Business Ecosystem of Lu et al. (2014). During the investigation interviews were conducted with the most relevant stakeholders of the electric vehicle industry and secondary data that characterize the incipient initiatives and inexpressive contribution of public policies to the development of this industrial sector were analyzed. Seven fundamental components of public policies that directly influence the electric vehicle industry in Brazil were identified and ranked. In practical terms, the paper aims to subsidize stakeholders to target more efficiently their efforts towards the development of this industry in Brazil.
547

Optimisation dans l'auto-partage à un seul sens avec voitures électriques et relocalisations / Optimization in one-way car sharing with electric cars and relocations

Ait Ouahmed, Mohammed Amine 15 October 2018 (has links)
Cette thèse a pour objectif de modéliser et résoudre des problèmes d’optimisation d’un système d’auto-partage avec des voitures électriques dit « à un seul sens », où les utilisateurs peuvent prendre une voiture dans une station et la laisser ensuite dans une autre. Ce fonctionnement conduit généralement à une situation de déséquilibre dans la répartition des voitures avec certaines stations pleines et d’autres vides. Une des solutions utilisées par les opérateurs d’autopartage pour pallier ce problème est le recours à des agents pour déplacer les voitures selon le besoin. Identifier et répondre à ce besoin est un problème d’optimisation non trivial, notamment à cause de l’usage de véhicules électriques, ce qui engendre des contraintes de rechargement de batteries et d’autonomie. Le problème d’optimisation est décomposé en deux sous-problèmes : le premier est le problème d’affectation des voitures aux clients, ainsi que leurs routages, que nous nommons ROCSP pour Recharging One way Car Sharing Problem ; le second problème est celui du planning des agents et leurs routages que nous nommons ESRP pour Employee Scheduling Routing Problem. 1. Résolution du ROCSP : deux modélisations en Programmation Linéaire en Nombres Entiers (PLNE) sont proposées, la première basée sur les flots et la deuxième sur les chemins, ce qui fait que les deux modèles intègrent de manière différente les contraintes de recharge électrique. Comme la résolution exacte à travers les modèles PLNE s’avère très gourmande en temps de calcul et non adaptée aux instances d’auto-partage de taille réelle, nous proposons des heuristiques qui permettent dans un temps raisonnable d’optimiser la redistribution des voitures et la gestion du service. Ces heuristiques permettent de calculer le nombre de voitures et les différentes opérations de relocalisation (redistribution des voitures) à réaliser sur une journée donnée. 2. Résolution du ESRP : un modèle PLNE est proposé pour la résolution exacte du ESRP, et, en complément, des heuristiques sont proposées pour une résolution approchée et relativement rapide. L’objectif est la détermination du nombre minimal d’agents nécessaire pour effectuer les opérations de relocalisation qui découlent du premier problème, le ROCSP. Dans une partie prospective, et une fois les ROCSP et ESRP résolus dans leur version statique, nous nous focaliserons sur une autre variante du problème avec réservation dynamique. Nous proposons également d’explorer un nouveau concept - l’auto-copartage - qui se veut une hybridation entre autopartage et covoiturage. Les algorithmes proposés ont été validés sur le réseau Auto Bleue de la ville de Nice essentiellement, qui gère une flotte de véhicules électriques, en s’appuyant sur des modèles de génération de flux pour estimer la demande, mais aussi d’autres instances que nous avons générées pour simuler d’autres villes, au sein d’un Système d’Information Géographique. / This thesis aims at modelling and solving optimization problems related to the management of one-way-electric-car-sharing systems, where users can take a car from a station, use it, and then return it to another station. This generally leads to an imbalanced distribution of cars, with some full stations and other empty ones. A solution to this problem, implemented by car-sharing operators, is to employ staff agents to move cars as needed. However, identifying this need is a non-trivial optimization problem, especially since the system may be more constrained when the vehicles used are electric, which generates battery recharging and autonomy constraints. The global optimization problem addressed is then divided into two sub-problems. The first one is assigning the cars to customers, as well as their routing; it is denoted by ROCSP (Recharging OneWay Car Sharing Problem). The second problem involves agents planning and routing; it is denoted by ESRP (Employee Scheduling Routing Problem). 1. For the ROCSP, we propose two Mixed-integer linear programming (MILP) modelizations of the problem: One based on flows and the other based on paths. This means that the two models include the battery-recharging constraints in two different ways. As the exact resolution through the MILP models is quite expensive in terms of computational time and is not adapted for the resolution of real-size car-sharing instances, we introduce heuristics that enable the optimization of cars-redistribution and service management of the service within a reasonable amount of time. These heuristics allows the calculation of the number of cars and the various redistribution operations to be performed on a given day. 2. For the ESRP, this second problem is also addressed with MILP models for the exact resolution, and some heuristics are suggested for an approximate resolution. This process has reasonable calculation time and aims at finding the minimum number of agents to perform the necessary relocation operations that stem from the first problem, namely, the ROCSP. Once the ROCSP and ESRP solved in their static versions, we then focus on the ROCSP by exploring another variant of the problem : ROCSP with dynamic reservation. We also suggest to explore a new concept : Auto-CoPartage, which is a hybridization of car-sharing and carpooling. The stated algorithms are validated on the Auto Bleue electrical vehicles fleet in the network of the city of Nice, essentially by relying on flow generation models to estimate the demand, but also using other instances that we have generated for other cities. All the data are handled using a Geographical Information System.
548

Integração de veículos elétricos no planejamento da expansão dos sistemas de distribuição /

Bañol Arias, Maria Nataly. January 2019 (has links)
Orientador: John Fredy Franco Baquero / Resumo: A crescente penetração dos Veículos Elétricos (VEs) no setor de transportes representa um novo e grande desafio para o planejamento da expansão e da operação dos Sistemas de Distribuição de Energia Elétrica (SDEEs) devido ao correspondente aumento da demanda associada ao carregamento das baterias. Portanto, devem ser desenvolvidos métodos que ajudem os SDEEs a lidar com esses desafios, considerando as incertezas associadas às demandas convencionais e aos VEs. Nesta tese é proposto um método robusto baseado em um modelo de Programação Linear Inteira-Mista (PLIM) para auxiliar a integração de VEs no SDEE. O método proposto permite resolver o problema de planejamento multi-estágio da expansão do SDEE considerando a alocação e o dimensionamento de Estações de Carregamento de VEs (ECVEs). Restrições probabilísticas são usadas na formulação proposta para lidar com as incertezas associadas à demanda, garantindo o cumprimento da capacidade de potência das subestações com um nível de confiança especificado. O modelo proposto para o planejamento da expansão avalia a construção e/ou reforço de subestações, ECVEs e circuitos, assim como também a alocação de unidades de geração distribuída e bancos de capacitores ao longo do horizonte de planejamento. O modelo de PLIM proposto é resolvido através de técnicas de otimização clássica visando garantir a solução ótima do problema. A eficiência e robustez do modelo são verificadas usando sistemas teste de 18 e 54 nós, junto com simulações de Mo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The increasing penetration of electric vehicles (EVs) in the transportation sector represents a new challenge for the expansion planning of electrical distribution systems (EDS) due to the corresponding increase of the energy demand. Therefore, methods to support the EDS considering the uncertainties associated with conventional and EV demands should be developed. This thesis presents a methodology to consider the EV integration into the EDS. A mixed-integer linear programming (MILP) model is proposed to solve the multi-stage expansion planning of EDS considering the allocation and sizing of EV charging stations (EVCSs). Chance constraints are used in the formulation to deal with the uncertainties associated with the demands, guaranteeing the fulfilment of the substation capacities within a given confidence level. The proposed model for the expansion planning considers the construction/reinforce of substations, EVCSs and circuits as well as the allocation of distributed generation units and capacitor banks along the planning horizon. The proposed MILP model guarantees optimality using classical optimization techniques. The efficiency and robustness of the model is verified using two test systems with 18-nodes and 54-nodes. Monte Carlo simulations were carried out to verify the compliance of the proposed chance constraint. / Doutor
549

MARKET ADOPTION AND IMPACT OF ELECTRIC ROADWAYS ON CRITERIA POLLUTANTS AND GREENHOUSE GAS EMISSIONS

Theodora Konstantinou (5930705) 16 January 2019 (has links)
<p>Traffic is inevitably a major source of air pollution, particularly in urban areas. Efforts are made towards reducing emissions by improving vehicle and fuel technology and promoting alternative, sustainable modes of transportation. Although the emergence of EVs has shown capabilities of decreasing energy use and emissions levels, the EV market is developing slowly mainly due to drivers’ range anxiety and charging time. Electric roadways (ERs) have been proposed as a solution to overcome the concerns related to EVs by converting road segments into powered lanes where vehicles can be charged as they move along the roadway. This technology has the potential to increase driving range, decrease battery size and thus, lower the weight and the cost of EVs. In this context, exploring the challenging concept of ERs comes natural. </p> <p>Since data on the market acceptance and the environmental implications on this technology are limited to non-existent, this thesis has the following objectives: 1) identify the factors that affect the short- and long-term intention to use ERs, 2) estimate the level of adoption of the ER technology and identify characteristics of the market segments and 3) assess the impact of ERs on criteria pollutants and greenhouse gas emissions based on the market adoption results.</p> <p>To achieve these objectives, a survey of the general population in Los Angeles, California was conducted, gathering 600 responses representative of gender and age in the area. Los Angeles is considered a leader in electro-mobility and thus, a natural choice for the implementation of ERs. The short-or long-term intentions to drive on ERs and purchase an EV knowing about the availability of ERs were found to be correlated and thus, were modeled simultaneously using a bivariate ordered probit model. The compatibility of the ER technology with respondents’ lifestyle and needs, respondents’ tendency towards using sustainable forms of transportation, respondents’ innovativeness and perceived environmental benefits were among the most significant variables found to affect the short-term and long-term intention to use ERs.</p> <p>The level of adoption of the ER technology and corresponding market segments were identified using a combination of Principal Component Analysis (PCA) and Cluster Analysis. Three clusters emerged from the analysis: early adopters (48.5%), mid-adopters (27.67%) and late adopters (23.83%) that differed in terms of demographics and socioeconomic characteristics, travel and EV charging characteristics and level of awareness. </p> <p>The adoption levels found were then used to estimate the emissions change due to the implementation of the ERs by 2050. Using the California Air Resources Board’s (CARB) 2017 EMissions FACtor model (EMFAC). Two scenarios were examined considering light-duty vehicles (LDVs) in a specific corridor: “with” and “without electrification” scenarios. The results suggested that the ER technology for light-duty vehicles has the potential to provide emission reductions of 4 to 24%. A sensitivity analysis was also conducted to examine the effect of speed on the results.</p> <p>Turning to the practical implications, this thesis can provide a foundational framework for the evaluation of the ER technology in terms of environmental and economic viability and set the groundwork for future research. Ultimately, the short-term and long-term intention analysis can be used as a draft guide by state and local agencies and inform their strategic short- or long- range plans for mobility. By segmenting potential users, policy makers and transport operators can be informed about the main challenges regarding the promotion of the ER technology to distinct market segments and devise ways to accelerate its adoption. The findings from the impact analysis of ERs on criteria pollutants and greenhouse gases can also inform long-range transportation plans and existing regulations and policies in California and beyond.</p> <p> </p>
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Power infrastructure requirements for road transport electrification

Nicolaides, Doros January 2018 (has links)
Deep decarbonisation of road transportation is challenging. One of the most potentially beneficial approaches is electrification which is the subject of this PhD thesis. A widespread penetration of electric vehicles (EVs) across a large proportion of road transport demand is needed to realise the benefits of an electrified transport sector. However, this is dependent on overcoming significant barriers. This study performs a systematic analysis of how proven power charging technologies could be used to unlock the barriers to widespread electrification of road transportation. Various road transport sectors and type of journeys are explored including aspects of autonomous operations and novel wireless power transfer technologies. For each operation, a framework is proposed that allows the exploitation of current and potential future electrification technologies to enable shifting towards EVs. Based on that, simulation tools and methods are developed to calculate the power requirements of EVs and determine a suitable charging infrastructure. The additional power demand, electric load and the implications for the electricity supply network are explored. The total expenditure needed and the CO2 emission savings are also calculated for each investigated operation. Transitional strategies include the electrification of bus routes, refuse collection functions, home deliveries and aspects of autonomous operations for public transportation within the boundaries of the cities. In the long-term, focus is given on passenger cars and freight vehicles for both urban and inter-urban journeys. A nationwide adoption of all electrification strategies proposed in this thesis would increase the peak power demand of Great Britain by approximately 38 GW (72% of the current peak) and the electricity consumption by 180 TWh per year (45% of current consumption). The total capital cost required is calculated at £225 billion which is similar to the cost of other large infrastructure projects of the country. The impact would be a significant aggregate saving of approximately 2,000 MtCO2 between the numbers calculated for today's norms (2018) and those calculated for 2050.

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