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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.
141

Hybrid electric vehicle dc-bus converter harmonics /

Mills-Price, Michael A. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 130-131). Also available on the World Wide Web.
142

Operation of a brushless DC drive for application in hybrid electric vehicles

Jenkins, James Scott, January 2007 (has links) (PDF)
Thesis (M.S.)--University of Missouri--Rolla, 2007. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed October 25, 2007) Includes bibliographical references (p. 61-62).
143

Μελέτη και κατασκευή οχήματος πόλης με διαφορικό ηλεκτροκινητήριο σύστημα

Βιδιαδάκης, Δημήτριος, Τσιάρα, Νεφέλη 24 October 2012 (has links)
Η παρούσα διπλωματική εργασία πραγματεύεται τη μελέτη της κατασκευής και την ανάπτυξη ενός πειραματικού οχήματος πόλης με ενεργό διαφορικό ηλεκτροκινητήριο σύστημα. Η εργασία αυτή εκπονήθηκε στο Εργαστήριο Ηλεκτρομηχανικής Μετατροπής Ενέργειας του Τμήματος Ηλεκτρολόγων Μηχανικών και Τεχνολογίας Υπολογιστών της Πολυτεχνικής Σχολής του Πανεπιστημίου Πατρών. Σκοπός είναι η μελέτη του ακριβούς ελέγχου της κίνησης των κινητήριων τροχών του οχήματος κατασκευάζοντας ένα ηλεκτρονικό διαφορικό. Ταυτόχρονα αναπτύχθηκε σύστημα παρακολούθησης συσσωρευτών. Αρχικά εξετάζεται η λειτουργία του μηχανικού διαφορικού και τω εφαρμογών του. Παρουσιάζονται μερικοί τύποι μηχανικών διαφορικών και αντίστοιχα πλεονεκτήματα και μειονεκτήματα που τους συνοδεύουν. Ακολουθεί η μελέτη της συμπεριφοράς της τροχιάς του άξονα κίνησης με τις χαρακτηριστικές εξισώσεις που περιγράφουν τις ταχύτητες των κινητήριων τροχών. Παράλληλα εξετάζονται οι μέθοδοι αποθήκευσης ηλεκτρικής ενέργειας στα ηλεκτροκίνητα μέσα μεταφοράς. Γίνεται εκτενής παρουσίαση του τρόπου λειτουργίας και των τύπων των συσσωρευτών καθώς και των συστημάτων παρακολούθησης και ελέγχου τους. Στη συνέχεια προσδιορίζονται οι προδιαγραφές του ηλεκτροκίνητου οχήματος και γίνεται μελέτη και υπολογισμός του απαραίτητου ηλεκτρικού και ηλεκτρονικού εξοπλισμού. Προσδιορίζεται η απαραίτητη ισχύς του κινητήριου συστήματος και η αναγκαία η ισχύς των συσσωρευτών. Σύμφωνα με τις προδιαγραφές προκύπτει και η κατάλληλη χωρητικότητα των συσσωρευτών καθώς επίσης και η διάταξή τους. Το επόμενο βήμα είναι η μελέτη και ανάπτυξη της κατασκευής των τυπωμένων κυκλωμάτων που θα ελέγχουν και θα παρακολουθούν το ηλεκτροκινητήριο σύστημα. Ακολουθεί η εγκατάσταση των συσσωρευτών, των δύο κινητήριων συστημάτων και των περιφερειακών εξαρτημάτων του οχήματος. Τέλος ακολουθούν οι πειραματικές μετρήσεις και η μελέτη της συμπεριφοράς του οχήματος μετά την εγκατάσταση του νέου συστήματος και η αξιολόγηση των θεωρητικών υπολογισμών. / This thesis deals with the study of construction and development of an experimental city vehicle with active differential electric powertrain. The work took place at the Laboratory of Electromechanical Energy Conversion, Department of Electrical and Computer Engineering, University of Patras. The aim is to study the precise control of motion of the drive wheels of the vehicle by manufacturing an electronic differential. Also, a battery monitoring system has been developed. First of all, the mechanical differential and its applications are studied. There are presented some types of mechanical differentials and their corresponding advantages and disadvantages. Also, the trajectory of the drive shaft is analyzed with the characteristic equations that describe the speed of the drive wheels. Additionally, the methods of storing electrical energy in electric transportation are examined. Various types of batteries are presented and operation as well as monitoring and management systems. Moreover, there are determined the specifications of the electric vehicle and then the necessary electrical and electronic equipment is studied and calculated. The required power of the drive system and the necessary power of the batteries are determined. According to the specifications, the capacity of the battery stack is calculated as well as the arrangement of the cells. The next step is the development of the printed circuit boards that control and monitor the electric powertrain. The installation of the batteries, the two drive systems and peripheral components of the vehicle are clearly presented. Finally, measurements of the electronic systems during testing are presented as well as the macroscopic values, followed by and an evaluation of the theoretical calculations.
144

Vehicle to Grid: An Economic and Technological Key to California's Renewable Future

Rafter, Jackson C 01 January 2016 (has links)
This paper explores how the concept of Vehicle to Grid (V2G) could bring benefits to California's electric grid, transportation sector, and environmental goals.
145

Design of a high specific torque induction motor

Ceron Guerrero, Jose Hermilo January 2015 (has links)
Electric vehicles are a key technology in the reduction of our carbon footprint and this has motivated significant research interest. The electrical traction motor is one of the main areas of research in attempts to further improve electric vehicle performance. The permanent magnet motor is the predominant device in this application because of its high specific torque. However, it has suffered from market speculation in the raw magnet materials which has generated efforts to develop electrical machines which have a high specific torque and do not contain rare earth materials. In the past the induction motor used to be the preferred motor for electric vehicles due to its low costs, low maintenance requirements, mature technology and robustness. The induction motor requires a higher specific torque to make it an alternative to permanent magnet machines. For this reason, this research had the primary aim of improving the specific torque of induction machines by undertaking a detailed review of the motor design because this process has conventionally focussed on the requirements for industrial applications. The first stage of the work presented in this thesis consisted of identifying the designs already in use for this purpose and the potential technologies applicable to the induction motor that could be transferred from other electric traction machines. A full review of the design process was also conducted in order to identify the key areas of the process with special reference to the electromagnetic design which used finite element techniques as the main modelling tool. New induction motor designs were developed which showed potential for improving the specific torque; two of these were selected for further refinement, prototyping and testing. Although these designs were modified to facilitate construction, some major difficulties were still encountered during the prototype rotor manufacture. The test results were used to validate the design process and to identify further improvements in the designs. The issues encountered with the rotor manufacture prototype however lead to some overheating during the experimental testing. Comments about the design experience gained during this research are summarized including suggestions for further research.
146

The Electrification of Transportation in Oregon: Opportunities for University, Government, and Industry Collaboration

Phillips, Elaine, Phillips, Elaine January 2012 (has links)
To promote economic recovery and create jobs, Oregon has developed a collaborative approach to economic development and turned its attention to stimulating the growth of competitive industry (Porterian) clusters. The electric vehicle (EV) cluster is one of the state's 21 priorities. With federal funding for electric vehicle infrastructure and The Electrification of Transportation initiatives, momentum is building. The Oregon University System, a number of state agencies and a coalescing group of EV entrepreneurs are pushing Oregon forward as a major player in the global marketplace. This thesis reviews an Oregon Transportation Research and Education Consortium study to determine whether the institutions of the Oregon University System and the state government are meeting the needs of EV entrepreneurs in this effort. The review concludes that Oregon's institutions need to further develop their collaborative networks with entrepreneurs for Oregon to be a competitor.
147

A introdução de veículos elétricos no Brasil: avaliação do impacto no consumo de gasolina e eletricidade

Baran, Renato 09 1900 (has links)
O objetivo desta tese é mensurar o impacto no consumo de gasolina e eletricidade causado pela introdução de veículos elétricos no mercado brasileiro. Para tanto, utilizou-se um modelo de previsão da demanda considerando quatro diferentes cenários, cada um supondo um diferente nível de penetração de veículos elétricos no mercado. Concluímos que a utilização de energia elétrica por automóveis permitiria uma redução do consumo de gasolina de 40,7% em 2031, acompanhado por um aumento do consumo de eletricidade de 42,1% em relação às projeções oficiais. Isto equivale a uma redução de 27,5% no consumo total de energia pela frota nacional, ou cerca de 31,6 x106 tep/ano. Como um dos principais argumentos contrários à introdução de carros elétricos no Brasil é que a eletricidade concorreria com o etanol e o petróleo do pré-sal, buscou-se demonstrar que a eletricidade atuaria como complemento, e não substituto, ao etanol e à gasolina. Apesar do potencial de produção de combustíveis fósseis no Brasil advindos das descobertas no pré-sal, o etanol e a eletricidade vêm de fontes renováveis, e com dependência mínima de matéria-prima importada, e pequena oscilação de preço quando comparados com derivados do petróleo, tornando os veículos elétricos uma alternativa para o Brasil. / The aim of this thesis is to measure the impact on energy consumption of the introduction of electric vehicles on to the Brazilian market. To this end, a demand forecast model was used under four different scenarios, each scenario pre-supposing a given level of penetration of the hybrid vehicles in the market. It is shown that with the use of electricity for individual transport, a reduction in the consumption of gasoline, in 2031, of 40.7% would be accompanied by an increase in electricity consumption of 42.1% in relation to official projections, which means a reduction of 27.5% in total energy consumption by the national fleet, or approximately 31.6 x106 toe/year. Since one of the main obstacles to the introduction of electric cars in Brazil is the competition with ethanol and pre-salt oil, we sought to demonstrate here that electricity could act not as a substitute, but rather a complement for ethanol and gasoline. Despite the significant potential domestic production of fossil fuels in Brazil as a result of the discoveries in the pre-salt, the ethanol and the electricity produced in the country come from renewable sources. This circumstance, together with the fact that their domestic production takes place with minimal dependence on foreign raw materials and lesser price oscillation as compared to petroleum derivatives, makes electrical vehicles an attractive alternative. / Bibliografia: p. 114-123 / Tese (doutorado) - Instituto Alberto Luiz Coimbra de Pós-Graduação e Pesquisa de Engenharia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, 2012.
148

Usina fotovoltaica de 1 MWp para suprimento de veículos elétricos : estimativa da frota atendida, logística de abastecimento e emissões de CO2 evitadas / Photovoltaic power plant of 1 Mwp for supply of electric vehicles : estimated served fleet, logistics supply and CO2 emissions avoided

Strangueto, Karina Maretti, 1987- 20 August 2018 (has links)
Orientador: Ennio Peres da Silva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-20T13:25:32Z (GMT). No. of bitstreams: 1 Strangueto_KarinaMaretti_M.pdf: 19906367 bytes, checksum: cfc584b8248827cae84c86e393a1870f (MD5) Previous issue date: 2012 / Resumo: Desde a Revolução Industrial, as atividades desenvolvidas pelo homem têm provocado um crescimento maciço das emissões de gases de efeito estufa e poluentes para a atmosfera da Terra, devido, entre outros fatores, à constante e crescente necessidade de energia. Um grande esforço vem sendo realizado nas últimas décadas para a redução dessas emissões, com especial atenção ao setor de transporte, principalmente pelos efeitos provocados nas populações das grandes cidades devido à concentração de veículos em espaços reduzidos. Neste caso, busca-se aumentar: a eficiência dos veículos convencionais, o uso de biocombustíveis e de veículos híbridos, e, mais recentemente, o uso de veículos elétricos (VEs). Com o avanço da utilização de veículos elétricos como meio de transporte "limpo", são necessários maiores estudos para avaliar a quantidade de energia necessária para o abastecimento das frotas destes veículos e, também, uma análise da quantidade evitada de emissões de gases de efeito estufa (gás carbônico) comparativamente aos modelos à combustão interna. Assim, esse trabalho teve como objetivo desenvolver esses temas. A geração de energia através painéis fotovoltaicos foi a escolha para essa dissertação, onde foi realizado um estudo de caso para uma usina de 1 MWP, determinando a quantidade de energia efetivamente produzida, considerando a usina localizada em Campinas, São Paulo. Dessa forma, pôde-se estimar que a frota de veículos que poderia ser abastecida com a energia gerada por essa usina teria um valor entre 955 e 1.118 veículos, dependendo de diferentes logísticas de abastecimento consideradas. Com a frota estimada, também foi possível calcular que emissões de até 2.004 toneladas anuais de CO2 poderiam ser evitadas pela substituição dos veículos convencionais pelos por esta frota de VEs / Abstract: Since the Industrial Revolution, human activities have been causing a massive growth in greenhouse gases and pollutants emissions to the Earth's atmosphere, due to, between other factors, the continuing and growing need for energy. A great effort has been made in recent decades to reduce these emissions, with special attention to the transport sector, mainly caused by the effects on populations of large cities due to the concentration of vehicles in confined spaces. In this case, seeks to improve: the efficiency of conventional vehicles, the use of biofuels and hybrid vehicles, and, more recently, the use of electric vehicles (EVs). With advancing of Electric Vehicle use as a means of "green" transport, more studies are needed to assess the amount of energy required to supply fleets of this kind of vehicles and, also, an analysis of the amount of avoided emissions of greenhouse gases (carbon dioxide) compared with internal combustion models. Thus, this study aimed to develop these themes. The generation of energy through photovoltaic panels was the choice for this dissertation, which was conducted a case study for a generating station of 1 MWP, determining the amount of energy effectively produced, considering the generating station located in Campinas, Sao Paulo. Thus, it was estimated that the fleet of vehicles that could be supplied with energy generated by this plant would have a value between 955 and 1.118 vehicles, depending on different logistical supply considered. With the fleet estimated, it was also possible to calculate that 2.004 tons of CO2 could be avoided by the replacement of conventional vehicles by EVs / Mestrado / Engenharia Mecanica / Mestre em Planejamento de Sistemas Energéticos
149

The accelerated life cycle testing and modelling of Li-ion cells used in electric vehicle applications

Rossouw, Claire Angela January 2012 (has links)
Li-ion batteries have become one of the chosen energy storage devices that are used in applications such as power tools, cellular phones and electric vehicles (EV). With the demand for portable high energy density devices, the rechargeable Li-ion battery has become one of the more viable energy storage systems for large scale commercial EVs because of their higher energy density to weight or volume ratio when compared to other current commercial battery energy storage systems. Various safety procedures for the use of Li-ion batteries in both consumer and EV applications have been developed by the international associations. The test procedures studied in this dissertation demonstrated the importance of determining the true capacity of a cell at various discharge rates. For this, the well known Peukert test was demonstrated. The study also showed that cells with different battery geometries and chemistries would demonstrate different thermal heating during discharge and slightly different Ragone results if different test methods were used as reported in the literature. Accelerated ageing tests were done on different cells at different Depth-of-Discharge (DoD) regions. The different DoD regions were determined according to expected stresses the electrode material in a cell would experience when discharged to specific DoD that follows the discharge voltage profile. Electrochemical Impedance Spectroscopy (EIS) was used to measure various electrochemical changes within these cells. The EIS results showed that certain observed modelled parameters would change similarly to the ageing of the cell as it aged due to the accelerated testing. EIS was also done on cells at different State-of-Charge (SoC) and temperatures. The results showed that EIS can be used as an effective technique to observe changes within a Li-ion cell as the SoC or temperature changed. For automotive vehicles that are powered by a fuel cell or battery, a supercapacitor can be coupled to a battery in order to increase and optimize the energy and power densities of the drive systems. A test procedure in the literature that evaluated the use of capacitors with Pb-acid batteries was applied to Li-ion type cells in order to quantify the increased power due to the use of a supercapacitor with a Li-ion cell. Both a cylindrical LiCoO2 cell and a VRLA Pb-acid cell showed some additional charge acceptance and delivery when connected to the supercapacitors. A LiMn2O4 pouch cell showed significant charge acceptance and delivery when connected to supercapacitors. The amount of additional charge acceptance and delivery of the different combinations could be explained by EIS, in particular, the resistance and capacitance of the cell in comparison to the combination of the cell and supercapacitor. A large capacity LiCoO2 cell showed high charge acceptance and delivery without connection with a supercapacitor. The study proved that EIS can be used to model the changes within cells under the different conditions and using different test procedures.
150

Analysis and modelling of energy source combinations for electric vehicles

Jarushi, Ali Milad January 2011 (has links)
The objective of this research is to develop suitable models to simulate and analyse Electrical Vehicle (EV) power-trains to identify and improve some of the deficiencies of EVs and investigate new system architectures. Although some electro-chemical batteries improvements have lately been achieved in specific-energy, the power density is still low. Therefore, an efficient, cost-effective and high power density support unit could facilitate EV competitiveness compared to conventional internal combustion engine powered vehicles in the near future. The Na-Ni-Cl2, or ZEBRA battery as it is most commonly known, has good energy and power densities; it is very promising electro-chemical battery candidate for EV's. The thesis presents a detail simulation model for the ZEBRA technology and investigates its application in an EV power-train with regard to state-of-charge and voltage transients. Unlike other battery systems, the ZEBRA technology can sustain about 5-10% of failed cells. While this is advantageous in single series string or single battery operation it is problematic when higher numbers of batteries are connected in parallel. The simulation model is used to investigate faulted operation of parallel battery configurations. A non-linear capacitance versus voltage function is implemented for the supercapacitor model which yields good energy and terminal voltage predictions when the supercapacitor is cycled over dynamic regimes common to EV applications. A thermal model is also included. Multiple energy source systems are modelled and studied in the form of an energy dense ZEBRA battery connected in parallel with a power dense supercapacitor system. The combination is shown to increase available power, reduce the maximum power demanded from the battery and decrease battery internal power loss. Consequently, battery life would be increased and more energy would be recovered from regenerative braking, enhancing the energy conversion efficiency of the power-train.A combination of ICE and ZEBRA battery is implemented as a range extender for London taxi driving from Manchester to London. The hybridisation ratio of the system is discussed and applied to fulfil the requirement with minimum emissions. This study offers a suitable model for different energy sources, and then optimises the vehicle energy storage combination to realize its full potential. The developed model is used to assess different energy source combinations in order to achieve an energy efficient combination that provides an improved vehicle performance, and, importantly, to understand the energy source interconnection issues in terms of energy flow and circuit transients.

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