To see the other types of publications on this topic, follow the link: Electric Vehicle Propulsion System.
Dissertations / Theses on the topic 'Electric Vehicle Propulsion System'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Electric Vehicle Propulsion System.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Keshri, Ritesh Kumar. "Electric Vehicle Propulsion System." Doctoral thesis, Università degli studi di Padova, 2014. http://hdl.handle.net/11577/3423806.
Full textAbstract:
Electric vehicles are being considered as one of the pillar of eco-friendly solutions to overcome the problem of global pollution and radiations due to greenhouse gases. Present thesis work reports the improvement in overall performance of the propulsion system of an electric vehicle by improving autonomy and torque-speed characteristic. Electric vehicle propulsion system consists of supply and traction system, and are coordinated by the monitoring & control system. Case of light electric vehicle propulsion system with permanent-magnet (PM) brushless dc (BLDC) drive being used in electric scooters and electric-mini cars is considered for analytical study and the implementation of the proposed solutions. PM BLDC motor and voltage source inverter are considered as a part of traction system and electric energy source such as battery, fuel cell or photovoltaic panel are considered as a part of supply system.
Available electric energy sources are capable of delivering higher current at lower terminal voltage, so are connected either in series or -more often- to the higher voltage dc-link through a circuital arrangement (boost topology) to achieve higher voltage. For the evaluation of boost topologies, traditional dc-to-dc boost converter with cascade VSI (DBI) and Z-source inverter (ZSI) are considered for fuel cell and battery as on-board energy sources. Evaluation of the convenience of the two supply topologies is carried out in terms of the factors defining transistor power utilization, and voltage and current transistor solicitation. In addition to mentioned defined factors, sizing of the passive components in terms of the power contribution factor of fuel cell is considered. In respect to the defined factors, DBI supply is found to be beneficial for PM BLDC drive whereas, with respect to the power contribution factor, ZSI supply is good to adopt for the cases were major contribution of power is from battery.
For the improvement in torque-speed characteristics of the considered drive, issue of torque ripple due to non-ideal phase commutation in case of conventional square-wave phase current (SqPC) supply is studied analytically by establishing a correlation between the behavior of the commutating phase currents and motor torque. Behavior of the motor torque during commutation for low and high speed zone as a function motor speed and defined motor specific quantity are explained in detailed. The analytical results are used to explain the dropping torque-speed characteristic of the drive and are verified experimentally for a propulsion drive available in the laboratory. Dropping torque-speed characteristic limits the use of the drive up till the nominal speed. To overcome this issue sinusoidal phase current (SPC) supply is proposed. SPC offers constant motor torque. A detailed convenience analysis of SPC over SqPC is carried out. Strategy for the implementation of SPC supply is also discussed and the analytical results were verified by the experimentally.
The study of the PM BLDC drive by means of the space phasor/vector approach has been executed. While such an approach is quite common for drives with motors with sinusoidal back-emf and phase currents, it is not explored in the literature for the present case, where back-emfs are trapezoidal and phase currents are square-wave in nature. Behavior of the PM BLDC drive has been revisited in stationary plane and the current commutation between the motor phases has been explained with the help of phase variable vectors. All the results obtained in a-b-c plane are cross verified in stationary plane showing the simplicity and potentialities of the vector approach for PM BLDC drive.
To address the issue of the autonomy of electric vehicles, use of solar energy to assist the on-board batteries of an electric mini-car is considered. Photovoltaic Geographical Information Systems database provided by Joint Research Centre Europe, is used to estimate the solar irradiance available in Padova, Italy. Output of a 0.487 sq-meter, 20-cell multi-crystalline PV panel is estimated and accordingly a conventional dc-to-dc boost converter is designed to interface PV panel with dc-link of a mini-car available in the laboratory. Appropriate control is implemented through DSP to track maximum power point. Whole system was tested outside the laboratory and measurements were carried out. Analytical loss model of the dc-to-dc boost converter is developed to explain the variations in gain, efficiency and loss components of the converter under varying solar irradiance.
The thesis work has been carried out at the Laboratory of “Electric systems for automation and automotive” headed by Prof. Giuseppe Buja. The laboratory belongs to the Department of Industrial Engineering of the University of PadovaI veicoli elettrici sono considerati uno dei pilastri tra le soluzioni ecosostenibili per superare il problema dell’inquinamento globale dovuto ai gas serra. Questo lavoro di tesi tratta del miglioramento delle prestazioni complessive di un sistema di propulsione di un veicolo elettrico mediante l’aumento dell’autonomia e della caratteristica coppia-velocità. Il sistema di propulsione di un veicolo elettrico consiste in un sistema di alimentazione e di un sistema di trazione, coordinati da un sistema di monitoraggio e controllo. Lo studio analitico e l’implementazione della soluzione proposta per il sistema di propulsione sono stati svolti con riferimento ad un motore brushless a magneti permanenti con fem trapezoidale (PM BLDC), utilizzato comunemente in veicoli elettrici leggeri come gli scooter e le mini-car. Il sistema di propulsione è costituito dal motore PM BLDC e dall’invertitore di tensione, mentre il sistema di alimentazione è formato da sorgenti energia elettrica come le batterie, le celle a combustibile o i pannelli fotovoltaici. Le sorgenti di energia elettrica disponibili sul mercato consentono di raggiungere elevati valori di corrente ma con bassi valori di tensione. Al fine di ottenere i valori di tensioni richiesti dal bus in continua, esse sono collegate in serie tra loro o sono connesse mediante convertitori innalzatori di tensione. Ciò può avvenire o attraverso un tradizionale convertitore dc/dc innalzatore con in cascata un invertitore di tensione (DBI) o attraverso un invertitore di tipo Z-source (ZSI). La valutazione di convenienza delle due modalità di alimentazione è basata sul fattore di utilizzazione e sulle sollecitazioni in termini di corrente e tensione dei transistor di potenza. Oltre ai fattori menzionati in precedenza, sono stati dimensionati gli elementi passivi in funzione della quota parte di potenza fornita dalla cella a combustibile. In relazione ai parametri definiti, la migliore soluzione risulta essere l’alimentazione con DBI, mentre quella con ZSI appare conveniente quando la maggior parte della potenza assorbita dal carico sia fornita dalle batterie. Al fine di migliorare le prestazioni di coppia, il ripple di coppia dovuto alla non ideale commutazione del convertitore ad onda quadra (SqPC) è stato studiato analiticamente, stabilendo la correlazione tra le correnti durante la fase di commutazione e la coppia del motore. Il comportamento di coppia a basse ed ad alte velocità è stato esaminato in dettaglio utilizzando specifiche grandezze del motore. I risultati analitici sono stati utilizzati per spiegare la caduta della coppia sviluppata dal motore ad alte velocità; essi sono stati verificati sperimentalmente su un azionamento di propulsione disponibile in laboratorio. La non costanza della caratteristica coppia-velocità limita l’uso del motore nei pressi della velocità nominale. Per superare questo limite è stata altresi utilizzata un’alimentazione con corrente sinusoidale (SPC). Essa permette di fornire al motore una coppia costante. E’ stata quindi eseguita un’analisi dettagliata al fine di vedere quale sia il metodo di alimentazione più conveniente tra SqPC e SPC. È stata altresì descritta la strategia d’implementazione dell’alimentazione SPC, e i risultati analitici sono stati verificati sperimentalmente. E’ stato eseguito lo studio degli azionamenti con motori PM BLDC con l’approccio dei fasori spaziali. Mentre questo approccio è abbastanza comune nel caso di azionamenti con motori con forza contro-elettromotrice e correnti di sinusoidali, esso non è trattato in letteratura per gli azionamenti con motori PM BLDC, in quanto la forza contro-elettromotrice è trapezoidale e il profilo delle correnti di fase è un onda quadra. Il comportamento del motore PM BLDC è stato rivisitato sul piano stazionario e la commutazione della corrente tra le fasi è stata descritta con l’ausilio dei vettori delle grandezze di fase. Tutti i risultati ottenuti nel piano a-b-c sono stati verificati nel piano stazionario, mostrando la semplicità e le potenzialità dell’approccio vettoriale. Al fine di estendere l’autonomia del veicolo sono stati utilizzati dei pannelli fotovoltaici. Il Sistema Geografico di Informazioni Fotovoltaico sviluppato dal Joint Research Center Europe è stato utilizzato per stimare il valore d’irraggiamento solare disponibile a Padova. È stata stimata la potenza generata da un pannello fotovoltaico di superficie 0.487 m2, formato da 20 celle multi-cristalline, e in relazione ad essa, è stato progettato il convertitore dc-dc elevatore per interfacciare il pannello fotovoltaico al bus in continua di una mini-car disponibile in laboratorio. Un appropriato controllo è stato implementato in un processore DSP al fine di inseguire il punto di massima potenza. L’intero sistema è stato provato all’esterno del laboratorio, facendo le misure necessarie per le verifiche. Un modello analitico delle perdite del convertitore dc-dc elevatore è stato sviluppato per descrivere la variazione di guadagno, rendimento e perdite del convertitore al variare dell’irraggiamento solare. Il lavoro di tesi è stato sviluppato presso il Laboratorio di “Sistemi elettrici per l’automazione e la veicolistica” diretto dal Prof. Giuseppe Buja. Il laboratorio afferisce al Dipartimento di Ingegneria Industriale dell’Università di Padova
2
Lundin, Johan. "Flywheel in an all-electric propulsion system." Licentiate thesis, Uppsala universitet, Elektricitetslära, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-222030.
Full textAbstract:
Energy storage is a crucial condition for both transportation purposes and for the use of electricity. Flywheels can be used as actual energy storage but also as power handling device. Their high power capacity compared to other means of storing electric energy makes them very convenient for smoothing power transients. These occur frequently in vehicles but also in the electric grid. In both these areas there is a lot to gain by reducing the power transients and irregularities. The research conducted at Uppsala university and described in this thesis is focused on an all-electric propulsion system based on an electric flywheel with double stator windings. The flywheel is inserted in between the main energy storage (assumed to be a battery) and the traction motor in an electric vehicle. This system has been evaluated by simulations in a Matlab model, comparing two otherwise identical drivelines, one with and one without a flywheel. The flywheel is shown to have several advantages for an all-electric propulsion system for a vehicle. The maximum power from the battery decreases more than ten times as the flywheel absorbs and supplies all the high power fluxes occuring at acceleration and braking. The battery delivers a low and almost constant power to the flywheel. The amount of batteries needed decreases whereas the battery lifetime and efficiency increases. Another benefit the flywheel configuration brings is a higher energy efficiency and hence less need for cooling. The model has also been used to evaluate the flywheel functionality for an electric grid application. The power from renewable intermittent energy sources such as wave, wind and current power can be smoothened by the flywheel, making these energy sources more efficient and thereby competitive with a remaining high power quality in the electric grid.
3
Ren, Zhongling. "Optimization Methods for Hybrid Electric Vehicle Propulsion System." Thesis, KTH, Energiteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-235932.
Full textAbstract:
Design of hybrid vehicles is a hot topic because of the strict restriction on the emissions of the vehicle. The optimal design of hybrid vehicles becomes necessary to reduce the cost or emissions of the vehicle. The propulsion system of a hybrid electric vehicle is inherently more complex than that of a conventional vehicle as an electric power supply branch is added. The design involves topology design, component design and control design, where all phases are interrelated. The idea to handle all the three design phases together is called system level design. Due to its complexity, it is not possible time wise to evaluate all possible design options. Optimization algorithms are therefore needed to speed up the process. The variable types that appear in each design phase are different and multiple algorithms are needed. In this thesis, different algorithms are studied for their robustness for both continuous variables and discrete variables, as well as benchmarked for the Volvo internal optimization platform afterwards. Standard test cases are used to validate the algorithms and several features are added to an algorithm to make it more generic and efficient. Based on theoretical and experimental studies, recommendations for the selection of algorithms are proposed based on different types of variables.Based on the optimization platform, several different optimization coordination architectures for system level design are introduced and simultaneous and nested coordination architectures are tested by one specific industrial case in the second part of the thesis. Both methods appeared to be promising according to the result of the test case and they managed to reduce the convergence time dramatically. The vehicle model used was not precise enough to prove which method is the superior one but a more precise model can be introduced in the future to facilitate such a conclusion.Hybridfordon är ett aktuellt ämne, på grund av den strikta regleringen gällande fordonsutsläpp. Den optimala designen av hybridfordon är nödvändig för att reducera kostnaden eller utsläppen. Motorsystemet hos ett elektriskt hybridfordon blir mer komplicerat än det hos ett konventionellt fordon, eftersom man måste ta hänsyn till försörjningen av elektrisk energi. Designprocessen involverar design av topologi, design av komponenter samt design av kontrollsystem. Idéen om att sammanfoga alla tre designfaser kallas systemnivådesign. På grund av komplexiteten är det tidsmässigt inte möjligt att evaluera samtliga möjliga designval. Därför behövs optimeringsalgoritmer för att snabba på processen. Olika typer av variabler berörs i de olika designfaserna och därför behövs olika algoritmer. I avhandlingen undersöks olika algoritmers robusthet för kontinuerliga och diskreta variabler samt deras prestanda mot en intern optimeringsplattform. Standardiserade testfall används för att validera algoritmerna vartefter algoritmerna görs mer effektiva och generella. Baserat på teoretiska och experimentella studier föreslås rekommendationer för val av algoritmer baserat på olika typer av variabler. Baserat på optimeringsplattformen introduceras flera olika optimeringskoordinationsarkitekturer för systemnivådesign, och samtidiga och samordnade koordinationsarkitekturer testas för ett specifikt industrifall i den andra delen av avhandlingen. Båda metoderna tycktes vara lovande enligt resultatet av testfallet, och de lyckades sänka konvergensperioden dramatiskt. Den använda fordonsmodellen var inte tillräckligt exakt för att bevisa vilken metod som är den överlägsna, men en mer exakt modell kan introduceras i framtiden för att underlätta en sådan slutsats.
4
Yourkowski, Joel. "Computer simulation of an unmanned aerial vehicle electric propulsion system." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1996. http://handle.dtic.mil/100.2/ADA307294.
Full text
5
Dhand, Aditya. "Design of electric vehicle propulsion system incorporating flywheel energy storage." Thesis, City University London, 2015. http://openaccess.city.ac.uk/13699/.
Full textAbstract:
Battery electric vehicles are crucial for moving towards a zero emission transport system. Though battery electric vehicle technology has been rapidly improving, it is still not competitive to the conventional vehicles in terms of both cost and performance. The limited driving range and high cost are significant impediments to the popularity of battery electric vehicles. The battery is the main element which affects the range and cost of the vehicle. The battery has to meet the requirements of sufficient power and energy, quick recharge, safety, low cost and sufficient life. However the battery can either provide high power or high energy but not both. Hybridisation of the energy source is one of the methods to improve the energy efficiency of the vehicle, which would involve combining a high energy battery with a high power source. High power batteries, ultracapacitors and high speed flywheels are the potential high power sources that could be used. Out of these, the high speed flywheel in combination with a mechanical transmission is an attractive high power source for the battery electric vehicle due to its favourable characteristics of high specific power, sufficient high specific energy, high energy efficiency, long cycle life, quick recharge and low cost . This thesis presents and critically assesses a concept of a mechanically connected flywheel assisted battery electric vehicle propulsion system for a modern passenger car application. The main contribution of this thesis is the analysis of the effect of utilizing a mechanically connected flywheel in a hybrid energy storage with Li-ion batteries on the energy efficiency of the electric vehicle. The starting point of the research was to create a base electric vehicle model based on current technology. An analysis of the battery electric vehicle, its various components and control strategy and various approaches to model it was discussed which led to the creation of the baseline model. Simulations using the baseline model on three real world driving cycles representing urban, extra urban and motorway conditions, showed the potential for improving the energy efficiency of the vehicle by utilizing a power handling device that could transmit power directly to the driveline such as a mechanically connected flywheel. Hybridisation of the energy storage with the incorporation of the mechanically connected flywheel was presented. The flywheel was sized and a road data analysis was performed to support the sizing analysis. To accomplish the integration of the flywheel with the driveline, a fundamental analysis of the mechanical power split continuously variable transmission was conducted which showed various ways of obtaining the desired ratio range for the flywheel operation according to vehicle requirements. The speed ratio, power flow and efficiency were derived for three different types of transmissions. This analysis produced a simple methodology that can be applied to design a transmission for flywheel energy storage to provide any required speed ratio coverage and predict its efficiency in both directions of power flow, which is an important contribution of the thesis. The hybrid vehicle layout was presented and all its components were discussed. Further to obtain the maximum potential for improvement in energy consumption with the hybrid vehicle, optimisation of the energy management strategy was conducted. The optimisation problem was complex because of factors such as the small storage capacity of the flywheel, the kinematic constraints and the slipping of clutches. Dynamic programming was used to find optimal energy management strategy on the three real world driving cycles, which was the first instance of its implementation for such a powertrain; another important contribution of the thesis. The results were compared with baseline using a quasi static backward model. There was significant reduction in energy consumption for the more aggressive motorway cycle, less for the extra urban cycle, while there was a small increase in energy consumption for the relatively less aggressive urban cycle. However significant reduction in battery stress was observed for all the cycles which is expected to lead to improvements in battery life and lower operating costs. To provide a further step in implementation, a predictive energy management strategy was applied in the backward model for the hybrid vehicle based on dynamic programming with short computation time and utilizing limited future journey information which showed good performance in comparison to the benchmark simulation results. Finally the control was tested in a forward dynamic simulation to verify its suitability for real life implementation, and showed small deviation in performance compared to the backward simulation.
6
Harmon, Frederick G. "Neural network control of a parallel hybrid-electric propulsion system for a small unmanned aerial vehicle /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2005. http://uclibs.org/PID/11984.
Full text
7
Brezina, Aron Jon. "Measurement of Static and Dynamic Performance Characteristics of Electric Propulsion Systems." Wright State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=wright1340066274.
Full text
8
Stevens, John Wesley. "A design of a low-cost propulsion system for an electric scooter." Thesis, Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/17885.
Full text
9
Mercan, Aybüke. "Driveline Modelling for Full Electric Bus." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Find full text
10
Grudic, Elvedin. "Electric Propulsion System for the Shell Eco-marathon PureChoice Vehicle : Controlling the lights and alternative storage devices such as batteries and supercapacitors." Thesis, Norwegian University of Science and Technology, Department of Electrical Power Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-9744.
Full textAbstract:
This report is divided into six main chapters. It starts off with an introductory chapter explaining the different propulsion strategies that have been considered during the last semester, and the final propulsion system that has been decided upon. The final propulsion strategy has several demands when it comes to components that have to be implemented and what type of components they should be. The main purpose for me in this project was therefore to meet these demands. Main demands for me were to demonstrate different possibilities when it comes to controlling the lights in the PureChoice vehicle, and to make sure the vehicle had enough energy stored in alternative storage devices in order to have a fully functioning system when it comes to driving the vehicle and managing the safety system onboard. The report continues with five individual chapters explaining how these demands were solved and which components that have been considered and implemented in the final vehicle. All off the chapters start of with an introduction about the topic at hand. They then continue with an explanation about the different components used in the vehicle, and reasoning for why exactly these components were chosen. In order to determine how the components would function in the final propulsion system, laboratory tests were performed on all the involved parts, and these laboratory tests are described at the end of all the chapters. This report includes both theoretical calculations and practical solutions.
11
Khusid, Michael. "Potential of electric propulsion systems to reduce petroleum use and greenhouse gas emissions in the U.S. light-duty vehicle fleet." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/62769.
Full textAbstract:
Thesis (S.M. in Engineering and Management)--Massachusetts Institute of Technology, Engineering Systems Division, System Design and Management Program, 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 74-78).
In the summer of 2008, the United States of America experienced an oil shock, first of a kind since 1970s. The American public became sensitized to the concerns about foreign oil supply and climate change and global warming, and to the role of transportation in emissions of carbon dioxide and other greenhouse gases (GHG). Several proposed federal policies impose stringent limits on the transportation sector, in terms of fuel consumption and GHG emissions. Within transportation sector, light duty vehicles (LDVs) - cars, light trucks and SUVs - currently emit the most GHGs. Hybrid technology emerged as a promising option to address several of these challenges. A modern hybrid electric vehicle (HEV) offers significantly better fuel economy together with lower levels of pollutant and CO2 emissions. HEVs are currently categorized as Advanced Technology Partial Zero Emission Vehicles (AT-PZEV) by California Air Resource Board. Recently, a new generation of vehicles, plug-in hybrid electric vehicles (PHEV), has been announced in the immediate future by major auto manufacturers. While HEVs have a relatively small battery that is recharged by the engine or by regenerative braking, a larger battery of a PHEV and a charger allows a vehicle owner to recharge the battery from the electric grid. The plug-in technology further increases fuel economy and reduces emissions from the tailpipe. For example, a Chevrolet Volt PHEV is expected to be launched as 2011 model with 40 mile allelectric travel with no tailpipe emissions. However, there are multiple challenges associated with the new technology. HEVs and PHEVs incur higher costs due to additional components, such as electric motors and motor controllers, and a battery. Today's batteries provide energy storage density hundred times lower than that of gasoline. Electricity consumed by hybrids is generated by coal and other fossil fuel power plants that emit harmful chemicals and greenhouse gases. The infrastructure for electric cars is at the infancy stage. Some government policies designed to introduce all-electric cars, such as the California ZEV mandate of the late 1990s, failed to introduce a sustained number of electric vehicles to the market. To provide an integrated approach to the causes and effects of electrified powertrains, two plausible scenarios of advanced vehicle market penetration were developed. Federal policies and consumer preferences were considered as primary drivers. Biofuels were considered alongside fossil fuels as primary energy sources for transportation. Rapid adoption of PHEVs was found to cause a perceptible, but not a significant increase in electric power demand. The scenarios demonstrated ability to achieve fuel economy milestones and quantified the challenge of achieving 80% reduction in greenhouse gas emissions by 2050.
by Michael Khusid.
S.M.in Engineering and Management
12
Sergent, Aaronn. "Optimal Sizing and Control of Battery Energy Storage Systems for Hybrid-Electric, Distributed-Propulsion Regional Aircraft." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1595519141013663.
Full text
13
BOUKADIDA, Yassine. "The i-motor: a system for end-of-line testing of electric drives for vehicles." Doctoral thesis, Università degli studi di Cassino, 2021. http://hdl.handle.net/11580/83957.
Full textAbstract:
This work is developed within a current trend aimed at time simulation-based testing systems, especially those dedicated to complex process where different sub-processes interact with different dynamics. The Hardware in the loop (HIL) is currently considered as a viable candidate to fulfill the requirements of real time simulation for the testing of complex systems. Within this trend, a HIL simulation system dedicated to the testing of a variable speed traction drive is developed. It incorporates a power system made up of two DC-AC converters connected through their AC sides by a three phase inductor, and a control system built around a NI PXI interface in which is embedded a real-time simulation HIL system. The implemented control scheme considers a current-regulated voltage source inverter fed permanent magnet synchronous motor under a vector control strategy. The analysis the test results obtained considering the emulation of different accelerating and braking cycles, have clearly proven the potentialities of the developed system.
14
Tanaka, Carlos Naomi. "Metodologia de dimensionamento do sistema de tração para veículos elétricos." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-26072013-120442/.
Full textAbstract:
O interesse por veículos elétricos voltou a crescer nos últimos anos, principalmente, devido às questões ambientais e de eficiência energética. Aliado ao desenvolvimento de fontes e acumuladores de energia com densidades de energia e potência maiores que viabilizam a utilização de veículos elétricos em substituição parcial dos veículos com motores a combustão interna, já surgem comercialmente no mercado alguns modelos de veículos elétricos. Neste contexto, também cresce a necessidade de recursos humanos capacitados e ferramentas auxiliares para o dimensionamento dos componentes dessa nova geração de veículos automotores. Este trabalho apresenta uma metodologia simples e direta de dimensionamento do sistema de tração para veículos elétricos autônomos, bem como os resultados de uma aplicação prática da utilização desta metodologia no desenvolvimento de veículos elétricos fora de estrada para transporte de pessoas e de material. A comparação entre os resultados práticos obtidos com os cálculos realizados mostra que a metodologia, com o equacionamento completo e abrangente apresentado, fornece resultados com excelente exatidão.The interest in electric vehicles is growing again in recent years, mainly due to environmental concerns and energy efficiency issues. Combined with the development of energy storage devices with higher power and energy densities that enable the use of electric vehicles, some models already appear commercially in the market replacing vehicles with internal combustion engines in specific applications. In this context, it also increases the need for trained human resources and auxiliary tools for designing the components of this new vehicles generation. This dissertation presents a simple and direct methodology of propulsion system design for autonomous electric vehicles as well as the results of a practical application of using this methodology in the development of off-road electric vehicles for people and material transport. The comparison between the practical results obtained with the calculations shows that the methodology, with the complete and comprehensive equations presented, provides results with excellent accuracy.
15
Zhao, Jianning. "Co-Optimisation du Dimensionnement et du Contrôle des Groupe Motopropulseurs Innovants." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLC057/document.
Full textAbstract:
Des technologies avancées sont très demandées dans l'industrie automobile pour respecter les réglementations de consommation de carburant de plus en plus rigoureuses. La co-optimisation du dimensionnement et du contrôle des groupes motopropulseurs avec une efficacité de calcul améliorée est étudiée dans cette thèse.Les composants des groupes motopropulseurs, tels que le moteur, la batterie et le moteur électrique, sont modélisés analytiquement au niveau descriptif et prédictif afin de permettre une optimisation du contrôle rapide et une optimisation du dimensionnement scalable. La consommation d'énergie minimale des véhicules hybrides-électriques est évaluée par des nouvelles méthodes optimales. Ces méthodes – y compris Selective Hamiltonian Minimization et GRaphical-Analysis-Based energy Consumption Optimization – permettent d'évaluer une consommation minimale d'énergie avec une efficacité de calcul améliorée. De plus, la méthode de Fully-Analytic energy Consumption Evaluation (FACE) approxime la consommation d'énergie minimale sous forme analytique en fonction des caractéristiques de la mission et des paramètres de conception des composants du groupe motopropulseur. Plusieurs cas d’études sont présentées en détail par rapport aux approches de co-optimisation à bi-niveaux et à uni-niveau, ce qui montre une réduction efficace du temps de calcul requis par le processus global de co-optimisationAdvanced technologies are highly demanded in automotive industry to meet the more and more stringent regulations of fuel consumption. Cooptimization of design and control for vehicle propulsion systems with an enhanced computational efficiency is investigated in this thesis.Powertrain components, such as internal combustion engines, batteries, and electric motor/generators, are analytically modeled at descriptive and predictive level correspondingly for the development of fastrunning control optimization and for the scalability of design optimization. The minimal fuel consumption of a hybrid-electric vehicle is evaluated through novel optimization methods. These methods – including the Selective Hamiltonian Minimization, and the GRaphical-Analysis-Based energy Consumption Optimization – are able to evaluate the minimal energy consumption with the enhanced computational efficiency. In addition, the Fully-Analytic energy Consumption Evaluation method approximates the minimal energy consumption in closed form as a function of the mission characteristics and the design parameters of powertrain components.A few case studies are presented in details via the bi-level and uni-level co-optimization approaches, showing an effective improvement in the computational efficiency for the overall co-optimization process
16
Goel, Varun, and Sonja Wadelius. "Evaluation of transition towards zero emission commuter ferries : Comparative Analysis of Fuel-based and Battery-based Marine Propulsion System from financial and environmental perspectives." Thesis, KTH, Marina system, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302781.
Full textAbstract:
The purpose of this study is to compare the life-cycle cost and environmental impact of the existing fuel-based propulsion system, on public commuter ferries in Stockholm, with a battery based propulsion system. The study is divided into multiple layers. First, the operating characteristics of the route Line 80 within Stockholm’s waterborne public transportation (WPT) are collected, such as fuel consumption, propulsion power output, speed, voyage time and propulsion system configuration. Second, based on the energy demand of the route, important parameters related to the existing fuel-based propulsion system and the battery-based propulsion system are accounted for and modeled. Third, Life Cycle Assessment (LCA) and the cost assessment methods are applied to examine the effectiveness of the electrification of commuter ferries on a financial and environmental scale. With the help of the software GaBi 2020, GREET 2020, and other literature studies, the environmental impacts at the construction, use and end-of-life (EOL) phase are evaluated. There are in total 8 scenarios considered, 4 for the fuel-based and 4 for the battery-based propulsion system. The environmental performance of these 8 scenarios are discussed in terms of Globalwarmingpotential(GWP), Acidificationpotential(AP), Eutrophicationpotential(EP) and Photo-chemical ozone creation potential (POCP). Themostpollutingphaseistheusephase for all scenarios. Propulsion system powered by diesel (scenario 1) is considered as a reference for comparative analysis of 7 other scenarios. The best performing system is the one powered by batteries with the assumption of an electricity mix based on hydro, wind and nuclear power, which is scenario 7 and 8 with a net reduction of GWP by more than 98%, AP by 90%, EP by 96%, and the POCP by 96%. If we consider the current Swedish electricity mix (scenario 5 and 6), the decrease in GWP, AP, EP and POCP are 90%, 80%, 82% and 91% respectively. Alternative fuels also present promising results for GWP in comparison to diesel (with the origin of the feed-stock creating mostly negative impacts) but the contribution to other impact categories is significantly higher. With inputs from the industry and the environmental evaluation, the cost assessment compares the costs related to fuel-based and battery-based propulsion systems with different energy sources. For the battery-based system, 3 scenarios are modeled for two different types of Li-ion batteries. The vessels in the developed scenarios are charged more frequently than the existing electric vessel and the number of charging stations is varied. The costs that are included in the assessment are the initial capital cost, the cost for fuel/electricity, maintenance cost, end-of-life cost and emissions cost. When concerning all the cost categories, the battery-based system is more cost-efficient than a fuel-based system, if run on the Swedish electricity mix, due to the lower cost for electricity and emissions. The reduction of cost is more than 68% when comparing traditional diesel with battery-based systems, but the source of the electricity is very important.Syftet med denna studie är att jämföra livscykelkostnaden och miljöpåverkan av de befintliga framdrivningssystemen på pendelbåtarna inom Stockholms kollektivtrafik, med batteridrivna system på motsvarande båtar. De befintliga framdrivningssystemen drivs av olika typer av diesel. Studien är uppdelad i flera steg. Först samlas driftsegenskaperna in, såsom bränsleförbrukning, framdrivningseffekt, hastighet, färdtidochframdrivningssystemetsuppbyggnad, etc, på linje 80, som är en del av Stockholms vattenburna kollektivtrafik. För det andra undersöks det befintliga framdrivningssystemet som drivs av diesel eller alternativa bränslen som RME eller HVO och fullt batteridrivna system utifrån energibehovet. För det tredje tillämpas metoderna för kostnadsanalys och livscykelanalys (LCA) för att undersöka hur elektrifieringen av pendelbåtar påverkar ekonomin och miljön. Med hjälp av programmet GaBi 2020, GREET 2020 och andra litteraturstudier utvärderas miljöpåverkan av faserna tillverkning, användning och avfallshantering. Det är totalt 8 scenarier som övervägs, 4 för bränslebaserade och 4 för batteri baserade framdrivningssystem. Hur bra dessa 8 scenarier presterar miljömässigt diskuteras i termer av växthuseffekt (GWP), försurning (AP), övergödning (EP) och marknära ozon (POCP). Den fasen med mest utsläpp, för alla scenarier, är användningsfasen. Framdrivningssystemet som drivs av diesel (scenario 1) används som referens att jämföra de övriga 7 scenarierna mot. Det system som presterar bästa är det som drivs av batterier, med antagandet att elmixen är baserad på vatten-, vind-och kärnkraft, detta motsvarar scenario 7 och 8 med en reduktion av GWP på mer än 98%, AP med 90%, EP med 96% och POCP med 96%. Om vi tittar på den aktuella svenska elmixen (scenario 5 och 6) så är minskningen av GWP, AP, EP och POCP 90%, 80%, 82% respektive 91%. Alternativa bränslen ger också lovande resultat för GWP jämfört med diesel (där råvarans ursprung skapar mest negativa effekter) men bidraget till andra påverkanskategorier är betydligt högre. Med input från företag och miljöutvärderingen kan kostnadsanalysen jämföra kostnaderna för bränslebaserade och batteri baserade framdrivningssystem med olika energikällor. Det batteri baserade systemet modelleras även på 3 utvecklade scenarier för 2 olika typer av batterier. Fartygen i de utvecklade scenarierna laddas oftare än det befintliga batteridrivna fartyget och antalet laddstationer varierar mellan scenarierna. De kostnader som inkluderas i analysen är de initiala kapitalkostnaderna, kostnaden för bränsle/el, underhållskostnader, avfallshanteringskostnader ochutsläppskostnader. Medallakostnaderinkluderadeiberäkningarna är batteri baserade system mer kostnadseffektiva än bränslebaserade system om de körs på svensk elmix, tack vare de lägre kostnaderna för el och utsläpp. Minskningen av den totala kostnaden är mer än 68% när man jämför traditionell diesel med batterisystem, men elens ursprung är mycket viktig.
17
Salomonsson, David, and Erik Eng. "A Component-based Model of a Fuel Cell Vehicle System." Thesis, Linköpings universitet, Fordonssystem, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-176698.
Full textAbstract:
Improving the efficiency and performance of vehicle propulsion systems has always been desirable, and with increasing environmental awareness this has become increasingly topical. A particularly strong focus today is at fossil-free alternatives, and there is a strong trend for electrification. Hybrid powertrains of different types can bring benefits in certain aspects, and there is a lot of research and development involved in the making of a new powertrain. In this thesis, a complete powertrain for a fuel cell hybrid electric vehicle is modeled, with the intention of contributing to this trend. The model can be used to investigate design choices and their impact on energy consumption. A component-based library is developed, with the purpose of being easy to implement for different configurations. The results show that it is possible to assemble and simulate a complete hybrid drivetrain, using the modeled components, while not being very computationally heavy. The developed models correspond well with reality while being modular and easy to implement.
18
PORRU, MARIO. "Management and control of energy storage systems for stationary and automotive applications." Doctoral thesis, Università degli Studi di Cagliari, 2015. http://hdl.handle.net/11584/266607.
Full textAbstract:
This PhD dissertation has presented a number of scenarios in which Energy Storage Systems (ESSs)
can be usefully employed for increasing energy system performances. Particularly, after introducing
the State-of-the-Art of ESS technologies (Chapter 1), reference has been made to some stationary and
automotive applications. Stationary applications have regarded Renewable Energy Sources (RESs)
exploitation issues and EV integration within micro-grids (Chapter 2). It has been shown that ESSs
are particularly useful in compensating for RES forecasting errors, whereas they are much less
effective as energy buffers. In addition, Vehicle to Grid (V2G) has also been revealed as an
alternative and viable solution for increasing RES penetration level and micro-grid autonomy, even in
presence of small EV fleets. The promising results obtained in the energy management of power
systems by means of the use of V2G and G2V paradigm have suggested the integration of Electric
Vehicles (EVs) into the power system. This requires that EV energy storage systems should satisfy
both electric propulsion and power system requirements. With this aim, the design and management
of a novel Hybrid Energy Storage System (HESS) for EVs has been considered (Chapter 3).
Particularly, the proposed configuration allows the reduction of the peak current delivered by EV
batteries, thus preserving their rated performances and increasing their lifetime. This goal has been
achieved by means of a suitable management of the energy flows provided by the HESS, leading to a
good exploitation of the proposed topology. The effectiveness of the proposed solutions has been
verified through several extensive simulation studies, which have been carried out in the Matlab
environment.
In conclusion, it can be stated that all cases have revealed the need of carefully sizing and managing
ESSs in order to achieve optimal results. In this context, it is worth noting that the employment of
large ESS easily leads to enhanced performances but also to significant increased costs. This
drawback cannot be sustained, especially in automotive applications, in which EV competitiveness is
strictly related to a decrease of ESS size, weight and costs. On the other hand, small ESSs do not
generally guarantee the same performances but they can be quite similar if optimal management and
control strategies are employed. These last thus will cover a fundamental role in making ESS more
widespread, enabling an optimal trade-off among increased performances, costs, management and
control issues.
19
Dai, Ping. "Réjection de perturbation sur un système multi-sources - Application à une propulsion hybride." Thesis, Poitiers, 2015. http://www.theses.fr/2015POIT2251/document.
Full textAbstract:
Ce mémoire porte sur l'étude d'un système de gestion d'énergie électrique dans un système multi-sources soumis à des perturbations exogènes. L'application visée est l'alimentation d'une propulsion hybride diesel/électrique équipée d'un système d'absorption des pulsations de couple. Les perturbations exogènes considérées peuvent être transitoires ou persistantes. Une perturbation transitoire correspond à une variation rapide du couple de charge, due par exemple à une accélération ou une décélération du véhicule. Une perturbation persistante provient du système de compensation des pulsations de couple générées par le moteur thermique. Le premier objectif du contrôle est de maintenir constante la tension du bus continu. Le deuxième objectif est d'absorber dans un système de stockage rapide constitué de super condensateur ces perturbations qui peuvent à terme provoquer une usure prématurée de la batterie. Le troisième objectif est de compenser l'auto-décharge dans le super condensateur en maintenant constante sa tension nominale. Les deux sources (batterie et super condensateur) sont reliées au bus continu par l'intermédiaire de deux convertisseurs boost DC/DC. La commande consiste à piloter les rapports cycliques de chaque convertisseur. C'est un système non linéaire où la commande est multiplicative de l'état. L'approche classique consistant à résoudre les équations Francis-Byrnes-Isidori ne s'applique pas directement dans ce cas où la sortie et la matrice d'interconnection dépendent de la commande. De plus, si cette approche est bien adaptée au rejet de perturbations persistantes, elle montre ces limites pour le rejet de perturbations non persistantes combiné à des objectifs de régulation. Notre approche a consisté à écrire le système sous un formalisme Port-Controlled Hamiltonian et à s'affranchir de la contrainte de la dépendance de la matrice d'interconnection avec la commande en utilisant la théorie des perturbations singulières. La commande du système dégénéré peut ensuite être calculée par une approche passive. Les performances de cette commande ont été testées en simulation et à l'aide d'un banc d'essai expérimental. Les résultats montrent l'efficacité du système d'absorption des différents types de perturbation tout en respectant les deux objectifs de régulationThis thesis presents the research of energy management in a battery/ultracapacitor hybrid energy storage system with exogenous disturbance in hybrid electric vehicular application. Transient and harmonic persistent disturbances are the two kinds of disturbances considered in this thesis. The former is due to the transient load power demand during acceleration and deceleration, and the latter is introduced from the process of the internal combustion engine torque ripples compensation. Our control objective is to absorb the disturbances causing battery wear via the ultracapacitor, and meanwhile, to maintain a constant DC voltage and to compensate the self-discharge in the ultracapacitor to maintain it operating at the nominal state of charge. The object system is nonlinear due to the multiplicative relation between the input and the state. The traditional approach to solve Francis-Byrnes-Isidori equations cannot be directly applied in this case since the interconnect matrix depends on the control input. Besides, even if this approach is well suited to the rejection of persistent disturbances, it shows the limits for the case of non-persistent disturbances which is also our object. Our contributed control method is realized through a cascade control structure based on the singular perturbation theory. The ultracapacitor current with the fastest motion rate is controlled in the inner fast loop through which we impose the desired dynamic to the system. The reduced system controlled in the outer slow loop is a Hamiltonian system and the controller is designed via interconnection and damping assignment. Simulations and experiments have been carried out to evaluate the control performance. A contrast of the system responses with and without the control algorithm shows that, with the control algorithm, the ultracapacitor effectively absorbs the disturbances; and verifies the effectiveness of the control algorithm
20
Larsson, Martin. "Electric Motors for Vehicle Propulsion." Thesis, Linköpings universitet, Fordonssystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-103907.
Full textAbstract:
This work is intended to contribute with knowledge to the area of electic motorsfor propulsion in the vehicle industry. This is done by first studying the differentelectric motors available, the motors suitable for vehicle propulsion are then dividedinto four different types to be studied separately. These four types are thedirect current, induction, permanent magnet and switched reluctance motors. Thedesign and construction are then studied to understand how the different typesdiffer from each other and which differences that are of importance when it comesto vehicle propulsion. Since the amount of available data about different electricmotors turned out to be small a tool was developed to use for collecting data fromthe sources available which can be for instance product sheets or articles with informationabout electric motors. This tool was then used to collect data that wasused to create models for the different motor types. The created motor models foreach motor type could then be used for simulating vehicles to investigate how thespecific motor is suited for different vehicles and applications. The work also containsa summary of different electric motor comparison studies which makes it agood source of information during motor type selection in the process of designingan electric vehicle.
21
Dong, Rong [Verfasser], Uwe [Akademischer Betreuer] Schäfer, Uwe [Gutachter] Schäfer, Sibylle [Gutachter] Dieckerhoff, Sami [Gutachter] Hlioui, and Julia [Gutachter] Kowal. "Design and comparison of two brushless DC drives for an electric propulsion system of solar-power unmanned aerial vehicles / Rong Dong ; Gutachter: Uwe Schäfer, Sibylle Dieckerhoff, Sami Hlioui, Julia Kowal ; Betreuer: Uwe Schäfer." Berlin : Universitätsverlag der TU Berlin, 2020. http://d-nb.info/1216945020/34.
Full text
22
Kaloun, Adham. "Conception de chaînes de traction hybrides et électriques par optimisation sur cycles routiers." Thesis, Centrale Lille Institut, 2020. http://www.theses.fr/2020CLIL0019.
Full textAbstract:
La conception des chaînes de traction hybrides est une tâche complexe, qui fait appel à des experts de différents domaines s'appuyant sur des compétences et des outils distincts. En plus de cela, la recherche d'une solution optimale nécessite un retour système. Cela peut être, selon la granularité des modèles de composants, très coûteux en temps de calcul. Ceci est d'autant plus vrai lorsque la performance du système est déterminée par sa commande, comme c'est le cas du véhicule hybride. En fait, différentes possibilités peuvent être sélectionnées pour fournir le couple requis aux roues pendant le cycle de conduite. Ainsi, le principal obstacle est d'atteindre l'optimalité tout en conservant une méthodologie rapide et robuste. Dans ces travaux de thèse, de nouvelles approches visant à exploiter le potentiel complet de l'hybridation sont proposées et comparées. La première stratégie est une approche bi-niveaux composée de deux blocs d'optimisation imbriqués: un processus d'optimisation des paramètres de design externe qui calcule la meilleure valeur de consommation de carburant à chaque itération en se basant sur une version améliorée de la programmation dynamique pour l'optimisation de la commande. Deux stratégies de conception systémique différentes basées sur le schéma itératif sont également proposées. La première approche est basée sur la réduction de modèle tandis que la seconde se repose sur des techniques précises de réduction de cycle. Cette dernière permet l'utilisation de modèles de haute précision sans pénaliser le temps de calcul. Une approche simultanée est ensuite mise en œuvre, qui optimise à la fois les variables de conception et les paramètres d'une nouvelle stratégie efficace à base de règles. Cette dernière permettra une optimisation plus rapide par rapport à l'optimisation directe de toutes les variables de décision. Enfin, une technique basée sur l'utilisation des méta-modèles est exploréeDesigning hybrid powertrains is a complex task, which calls for experts from various fields. In addition to this, finding the optimal solution requires a system overview. This can be, depending on the granularity of the models at the component level, highly time-consuming. This is even more true when the system’s performance is determined by its control, as it is the case of the hybrid powertrain. In fact, various possibilities can be selected to deliver the required torque to the wheels during the driving cycle. Hence, the main obstacle is to achieve optimality while keeping the methodology fast and robust. In this work, novel approaches to exploit the full potential of hybridization are proposed and compared. The first strategy is a bi-level approach consisting of two nested optimization blocks: an external design optimization process that calculates the best fuel consumption value at each iteration, found through control optimization using an improved version of dynamic programming. Two different systemic design strategies based on the iterative scheme are proposed as well. The first approach is based on model reduction while the second approach relies on precise cycle reduction techniques. The latter enables the use of high precision models without penalizing the calculation time. A co-optimization approach is implemented afterwards which adjusts both the design variables and parameters of a new efficient rule-based strategy. This allows for faster optimization as opposed to an all-at-once approach. Finally, a meta-model based technique is explored
23
Dinca, Dragos. "Development of an Integrated High Energy Density Capture and Storage System for Ultrafast Supply/Extended Energy Consumption Applications." Cleveland State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=csu1495115874616384.
Full text
24
St, Rock Brian Eric. "Thermal-fluid analysis of a lithium vaporizer for a high power magnetoplasmadynamic thruster." Worcester, Mass. : Worcester Polytechnic Institute, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-010907-142804/.
Full text
25
Byrne, Lawrence Thomas. "Langmuir probe measurements in the plume of a pulsed plasma thruster." Link to electronic thesis, 2002. http://www.wpi.edu/Pubs/ETD/Available/etd-1219102-173938.
Full textAbstract:
Thesis (M.S.)--Worcester Polytechnic Institute.Keywords: PPT; pulsed plasma thruster; Langmuir probe; plasma diagnostics; electric propulsion; electron temperature; electron density. Includes bibliographical references (p. 97-102).
26
Kwon, Kybeom. "A novel numerical analysis of Hall Effect Thruster and its application in simultaneous design of thruster and optimal low-thrust trajectory." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/34777.
Full textAbstract:
Hall Effect Thrusters (HETs) are a form of electric propulsion device which uses external electrical energy to produce thrust. When compared to various other electric propulsion devices, HETs are excellent candidates for future orbit transfer and interplanetary missions due to their relatively simple configuration, moderate thrust capability, higher thrust to power ratio, and lower thruster mass to power ratio. Due to the short history of HETs, the current design process of a new HET is a largely empirical and experimental science, and this has resulted in previous designs being developed in a narrow design space based on experimental data without systematic investigations of parameter correlations. In addition, current preliminary low-thrust trajectory optimizations, due to inherent difficulties in solution procedure, often assume constant or linear performances with available power in their applications of electric thrusters. The main obstacles come from the complex physics involved in HET technology and relatively small amounts of experimental data. Although physical theories and numerical simulations can provide a valuable tool for design space exploration at the inception of a new HET design and preliminary low-thrust trajectory optimization, the complex physics makes theoretical and numerical solutions difficult to obtain. Numerical implementations have been quite extensively conducted in the last two decades. An investigation of current methodologies reveals that to date, none provide a proper methodology for a new HET design at the conceptual design stage and the coupled low-thrust trajectory optimization. Thus, in the first half of this work, an efficient, robust, and self-consistent numerical method for the analysis of HETs is developed with a new approach. The key idea is to divide the analysis region into two regions in terms of electron dynamics based on physical intuition. Intensive validations are conducted for existing HETs from 1 kW to 50 kW classes. The second half of this work aims to construct a simultaneous design optimization environment though collaboration with experts in low-thrust trajectory optimization where a new HET and associated optimal low-thrust trajectory can be designed simultaneously. A demonstration for an orbit raising mission shows that the constructed simultaneous design optimization environment can be used effectively and synergistically for space missions involving HETs. It is expected that the present work will aid and ease the current expensive experimental HET design process and reduce preliminary space mission design cycles involving HETs.
27
Kaloun, Adham. "Conception de chaînes de traction hybrides et électriques par optimisation sur cycles routiers." Thesis, Ecole centrale de Lille, 2020. http://www.theses.fr/2020ECLI0019.
Full textAbstract:
La conception des chaînes de traction hybrides est une tâche complexe, qui fait appel à des experts de différents domaines s'appuyant sur des compétences et des outils distincts. En plus de cela, la recherche d'une solution optimale nécessite un retour système. Cela peut être, selon la granularité des modèles de composants, très coûteux en temps de calcul. Ceci est d'autant plus vrai lorsque la performance du système est déterminée par sa commande, comme c'est le cas du véhicule hybride. En fait, différentes possibilités peuvent être sélectionnées pour fournir le couple requis aux roues pendant le cycle de conduite. Ainsi, le principal obstacle est d'atteindre l'optimalité tout en conservant une méthodologie rapide et robuste. Dans ces travaux de thèse, de nouvelles approches visant à exploiter le potentiel complet de l'hybridation sont proposées et comparées. La première stratégie est une approche bi-niveaux composée de deux blocs d'optimisation imbriqués: un processus d'optimisation des paramètres de design externe qui calcule la meilleure valeur de consommation de carburant à chaque itération en se basant sur une version améliorée de la programmation dynamique pour l'optimisation de la commande. Deux stratégies de conception systémique différentes basées sur le schéma itératif sont également proposées. La première approche est basée sur la réduction de modèle tandis que la seconde se repose sur des techniques précises de réduction de cycle. Cette dernière permet l'utilisation de modèles de haute précision sans pénaliser le temps de calcul. Une approche simultanée est ensuite mise en œuvre, qui optimise à la fois les variables de conception et les paramètres d'une nouvelle stratégie efficace à base de règles. Cette dernière permettra une optimisation plus rapide par rapport à l'optimisation directe de toutes les variables de décision. Enfin, une technique basée sur l'utilisation des méta-modèles est exploréeDesigning hybrid powertrains is a complex task, which calls for experts from various fields. In addition to this, finding the optimal solution requires a system overview. This can be, depending on the granularity of the models at the component level, highly time-consuming. This is even more true when the system’s performance is determined by its control, as it is the case of the hybrid powertrain. In fact, various possibilities can be selected to deliver the required torque to the wheels during the driving cycle. Hence, the main obstacle is to achieve optimality while keeping the methodology fast and robust. In this work, novel approaches to exploit the full potential of hybridization are proposed and compared. The first strategy is a bi-level approach consisting of two nested optimization blocks: an external design optimization process that calculates the best fuel consumption value at each iteration, found through control optimization using an improved version of dynamic programming. Two different systemic design strategies based on the iterative scheme are proposed as well. The first approach is based on model reduction while the second approach relies on precise cycle reduction techniques. The latter enables the use of high precision models without penalizing the calculation time. A co-optimization approach is implemented afterwards which adjusts both the design variables and parameters of a new efficient rule-based strategy. This allows for faster optimization as opposed to an all-at-once approach. Finally, a meta-model based technique is explored
28
Wikman, Dennis, and Oscar Andersson. "Propulsion system for a small unmanned aerial vehicle." Thesis, KTH, Skolan för teknikvetenskap (SCI), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-276078.
Full textAbstract:
For unmanned aerial vehicles there is a wide variety of selection for propulsion systems. Depending on the specific choice of system, the characteristics of the aircraft vary significantly. The choice is also dependent on the size of the UAV itself as well as desired performance and utility. Propulsion systems have made significant advancements over the last decades in the UAV sector. The Skywalker X8 is a popular small UAV and most commonly flown electrically. What propulsion would then be fitting for the originally 2 m wingspan Skywalker X8 if its size in dimensions were doubled. This study presents an early suggestion of a propulsion system for the double sized Skywalker X8. The final propulsion system is a hybrid system consisting of a fuel cell and batteries, giving a time of operational flight of 19 hrs. The results show that the method of choice works as an early design solution of selecting a propulsion system and determining performance. However, it may be an inaccurate representation of the physical model and needs to be followed up by more detailed analysis of the UAV. It is concluded that further experimentation should be done in order to verify the data calculated with this model.För obemannade flygfordon finns ett stort urval av framdrivningssystem. Beroende på det specifika valet av system varierar flygplanets egenskaper väsentligt. Valet är också beroende av storleken på farkosten själv och önskad prestanda och användbarhet. Framdrivningssystem har gjort betydande framsteg under de senaste decennierna. Skywalker X8 är en populär obemannad luftfarkost och flygs oftast elektriskt. Vilken framdrivning skulle då passa för den ursprungliga Skywalker X8 med 2 m vingspann om dess storlek i dimensioner fördubblats. Denna studie presenterar ett tidigt förslag om ett framdrivningssystem för den dubbelt så stora Skywalker X8. Det slutliga framdrivningssystemet är ett hybridsystem som består av en bränslecell och batterier, vilket ger en drifttid på 19 timmar. Resultaten visar att valmetoden fungerar som en tidig designlösning för att välja ett framdrivningssystem och bestämma dess prestanda. Det kan dock vara en felaktig representation av den fysiska modellen och måste följas upp av en mer detaljerad analys av farkosten. Det dras slutsatsen att ytterligare experiment bör göras för att verifiera de data som beräknats med denna modell.
29
Åkesson, Elsa, Maximilian Kempe, Oskar Nordlander, and Rosa Sandén. "Unmanned Aerial Vehicle Powered by Hybrid Propulsion System." Thesis, KTH, Skolan för kemi, bioteknologi och hälsa (CBH), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-277115.
Full textAbstract:
I samband med den globala uppvärmningen ökar efterfrågan för rena och förnybara bränslen alltmer i dagens samhälle. Eftersom flygindustrin idag är ansvarig för samma mängd växthusgaser som all motortrafik i Sverige, skulle ett byte till en avgasfri energikälla för flygfarkoster vara ett stort framsteg. Därför har projektet genom modellering framtagit ett hybridsystem av ett batteri och en bränslecell och undersökt hur kombinationen av olika storlekar på dem presterar i en driftcykel. Då batterier har hög specifik effekt men är tunga, kompletteras de med fördel av bränsleceller, som är lättviktiga och bidrar med uthållig strömförsörjning. På så sätt blir hybriden optimal för flygfarkoster. Kandidatarbetet är en del av projektet Green Raven, ett tvärvetenskapligt samarbete mellan instutitionerna Tillämpad Elektrokemi, Mekatronik och Teknisk Mekanik på Kungliga Tekniska Högskolan. Driftcykelmodelleringen gjordes i Simulink, och flera antaganden gjordes beträffande effektprofilen, samt bränslecellens mätvärden och effekt. Tre olika energihushållningsscheman skapades, vilka bestämde bränslecellseffekten beroende på vätgasnivån och batteriets laddningstillstånd. Skillnaden på systemen var vilka intervall av laddningstillstånd hos batteriet som genererade olika effekt hos bränslecellen. Det bästa alternativet visade sig vara 0/100-systemet, eftersom det var det enda som inte orsakede någon degradering av bränslecellens kapacitet.In today’s society, with several environmental challenges such as global warming, the demand for cleanand renewable fuels is ever increasing. Since the aviation industry in Sweden is responsible for the sameamount of greenhouse gas emissions as the motor traffic, a change to a non-polluting energy source forflying vehicles would be considerable progress. Therefore, this project has designed a hybrid system of abattery and a fuel cell and investigated how different combinations of battery and fuel cell sizes perform ina drive cycle, through computer modelling. As batteries possess a high specific power but are heavy, thefuel cells with high specific energy complement them with a sustained and lightweight power supply,which makes the hybrid perfect for aviation. The bachelor thesis is a part of Project Green Raven, aninterdisciplinary collaboration with the institutions of Applied Electrochemistry, Mechatronics andEngineering Mechanics at KTH Royal Institute of Techology. The drive cycle simulations were done inSimulink, and several assumptions regarding the power profile, fuel cell measurements and power weremade. Three different energy management strategies were set up, determining the fuel cell powerdepending on hydrogen availability and state of charge of the battery. The strategies were called 35/65,20/80 and 0/100, and the difference between them was at which state of charge intervals the fuel cellchanged its power output. The best strategy proved to be 0/100, since it was the only option which causedno degradation of the fuel cell whatsoever.
30
Wilkman, Dennis, and Oscar Andersson. "Propulsion system for a small unmanned aerial vehicle." Thesis, KTH, Skolan för teknikvetenskap (SCI), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-276078.
Full textAbstract:
For unmanned aerial vehicles there is a wide variety of selection for propulsion systems. Depending on the specific choice of system, the characteristics of the aircraft vary significantly. The choice is also dependent on the size of the UAV itself as well as desired performance and utility. Propulsion systems have made significant advancements over the last decades in the UAV sector. The Skywalker X8 is a popular small UAV and most commonly flown electrically. What propulsion would then be fitting for the originally 2 m wingspan Skywalker X8 if its size in dimensions were doubled. This study presents an early suggestion of a propulsion system for the double sized Skywalker X8. The final propulsion system is a hybrid system consisting of a fuel cell and batteries, giving a time of operational flight of 19 hrs. The results show that the method of choice works as an early design solution of selecting a propulsion system and determining performance. However, it may be an inaccurate representation of the physical model and needs to be followed up by more detailed analysis of the UAV. It is concluded that further experimentation should be done in order to verify the data calculated with this model.För obemannade flygfordon finns ett stort urval av framdrivningssystem. Beroende på det specifika valet av system varierar flygplanets egenskaper väsentligt. Valet är också beroende av storleken på farkosten själv och önskad prestanda och användbarhet. Framdrivningssystem har gjort betydande framsteg under de senaste decennierna. Skywalker X8 är en populär obemannad luftfarkost och flygs oftast elektriskt. Vilken framdrivning skulle då passa för den ursprungliga Skywalker X8 med 2 m vingspann om dess storlek i dimensioner fördubblats. Denna studie presenterar ett tidigt förslag om ett framdrivningssystem för den dubbelt så stora Skywalker X8. Det slutliga framdrivningssystemet är ett hybridsystem som består av en bränslecell och batterier, vilket ger en drifttid på 19 timmar. Resultaten visar att valmetoden fungerar som en tidig designlösning för att välja ett framdrivningssystem och bestämma dess prestanda. Det kan dock vara en felaktig representation av den fysiska modellen och måste följas upp av en mer detaljerad analys av farkosten. Det dras slutsatsen att ytterligare experiment bör göras för att verifiera de data som beräknats med denna modell.
31
Marchetti, Paul J. "Electric propulsion and controller design for drag-free spacecraft operation in low earth orbit." Link to electronic thesis, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-122006-144358/.
Full text
32
Zwahlen, Jurg C. "Investigation of a Pulsed Plasma Thruster Plume Using a Quadruple Langmuir Probe Technique." Digital WPI, 2003. https://digitalcommons.wpi.edu/etd-theses/33.
Full textAbstract:
The rectangular pulsed plasma thruster (PPT) is an electromagnetic thruster that ablates Teflon propellant to produce thrust in a discharge that lasts 5-20 microseconds. In order to integrate PPTs onto spacecraft, it is necessary to investigate possible thruster plume-spacecraft interactions. The PPT plume consists of neutral and charged particles from the ablation of the Teflon fuel bar as well as electrode materials. In this thesis a novel application of quadruple Langmuir probes is implemented in the PPT plume to obtain electron temperature, electron density, and ion speed ratio measurements (ion speed divided by most probable thermal speed). The pulsed plasma thruster used is a NASA Glenn laboratory model based on the LES 8/9 series of PPTs, and is similar in design to the Earth Observing-1 satellite PPT. At the 20 J discharge energy level, the thruster ablates 26.6 mg of Teflon, creating an impulse bit of 256 mN-s with a specific impulse of 986 s. The quadruple probes were operated in the so-called current mode, eliminating the need to make voltage measurements. The current collection to the parallel to the flow electrodes is based on Laframboise's theory for probe to Debye length ratios between 5 and 100, and on the thin-sheath theory for ratios above 100. The ion current to the perpendicular probe is based on a model by Kanal and is a function of the ion speed ratio, the applied non-dimensional potential and the collection area. A formal error analysis is performed using the complete set of nonlinear current collection equations. The quadruple Langmuir probes were mounted on a computer controlled motion system that allowed movement in the radial direction, and the thruster was mounted on a motion system that allowed angular variation. Measurements were taken at 10, 15 and 20 cm form the Teflon fuel bar face, at angles up to 40 degrees off of the centerline axis at discharge energy levels of 5, 20, and 40 J. All data points are based on an average of four PPT pulses. Data analysis shows the temporal and spatial variation in the plume. Electron temperatures show two peaks during the length of the pulse, a trend most evident during the 20 J and 40 J discharge energies at 10 cm from the surface of the Teflon fuel bar. The electron temperatures after the initial high temperature peak are below 2 eV. Electron densities are highest near the thruster exit plane. At 10 cm from the Teflon surface, maximum electron densities are 1.04e20 ± 2.8e19 m-3, 9.8e20 ± 2.3e20 m-3, and 1.38e21 ± 4.05e20 m-3 for the 5 J, 20 J and 40 J discharge energy, respectively. The electrons densities decrease to 2.8x1019 ± 8.9e18 m-3, 1.2e20 ± 4.2e19 m-3, and 4.5e20 ± 1.2e20 m-3 at 20 cm for the 5 J, 20 J, and 40 J cases, respectively. Electron temperature and density decrease with increasing angle away from the centerline, and with increasing downstream distance. The plume is more symmetric in the parallel plane than in the perpendicular plane. Ion speed ratios are lowest near the thruster exit, increase with increasing downstream distance, but do not show any consistent angular variation. Peak speed ratios at a radial distance of 10 cm are 5.9±3.6, 5.3±0.39, and 4.8±0.41 for the 5 J, 20 J and 40 J discharge energies, respectively. The ratios increase to 6.05±5.9, 7.5±1.6, and 6.09±0.72 at a radial distance of 20 cm. Estimates of ion velocities show peak values between 36 km/s to 40 km/s, 26 km/s to 30 km/s, and 26 km/s to 36 km/s for the % J, 20 J, and 40 J discharge energies, respectively.
33
Pop, Adrian-Cornel. "Switched reluctance motors for electric vehicle propulsion: optimal machine design and control." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209569.
Full text
34
Watts, Christopher Mark. "A comparison study of biologically inspired propulsion systems for an autonomous underwater vehicle." Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/1672/.
Full textAbstract:
The field of Autonomous Underwater Vehicles (AUVs) has increased dramatically in size and scope over the past two decades. Application areas for AUVs are numerous and varied; from deep sea exploration, to pipeline surveillance to mine clearing. However, one limiting factor with the current technology is the duration of missions that can be undertaken and one contributing factor to this is the efficiency of the propulsion system, which is usually based on marine propellers. As fish are highly efficient swimmers greater propulsive efficiency may be possible by mimicking their fish tail propulsion system. The main concept behind this work was therefore to investigate whether a biomimetic fish-like propulsion system is a viable propulsion system for an underwater vehicle and to determine experimentally the efficiency benefits of using such a system. There have been numerous studies into biomimetic fish like propulsion systems and robotic fish in the past with many claims being made as to the benefits of a fish like propulsion system over conventional marine propulsion systems. These claims include increased efficiency and greater manoeuvrability. However, there is little published experimental data to characterise the propulsive efficiency of a fish like propulsive system. Also, very few direct experimental comparisons have been made between biomimetic and conventional propulsion systems. This work attempts to address these issues by directly comparing experimentally a biomimetic underwater propulsion system to a conventional propulsion system to allow for a better understanding of the potential benefits of the biomimetic system. This work is split into three parts. Firstly, the design and development of a novel prototype vehicle called the RoboSalmon is covered. This vehicle has a biomimetic tendon drive propulsion system which utilizes one servo motor for actuation and has a suite of onboard sensors and a data logger. The second part of this work focuses on the development of a mathematical model of the RoboSalmon vehicle to allow for a better understanding of the dynamics of the system. Simulation results from this model are compared to the experimental results and show good correlation. The final part of the work presents the experimental results obtained comparing the RoboSalmon prototype with the biomimetic tail system to the propeller and rudder system. These experiments include a study into the straight swimming performance, recoil motion, start up transients and power consumption. For forward swimming the maximum surge velocity of the RoboSalmon was 0.18ms-1 and at this velocity the biomimetic system was found to be more efficient than the propeller system. When manoeuvring the biomimetic system was found to have a significantly reduced turning radius. The thesis concludes with a discussion of the main findings from each aspect of the work, covering the benefits obtained from using the tendon drive system in terms of efficiencies and manoeuvring performance. The limitations of the system are also discussed and suggestions for further work are included.
35
Schultz, James Allen. "Autonomous Underwater Vehicle (AUV) Propulsion System Analysis and Optimization." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/33237.
Full textAbstract:
One of the largest design considerations for autonomous underwater vehicles (AUVâ s) that have specific mission scenarios is the propulsive efficiency. The propulsive efficiency affects the amount of power storage required to achieve a specific mission. As the efficiency increases the volume of energy being stored decreases. The decrease in volume allows for a smaller vehicle, which results in a vehicle that requires less thrust to attain a specific speed.
The process of selecting an efficient propulsive system becomes an iterative process between motor, propeller, and battery storage. Optimized propulsion systems for mission specific AUVâ s require costly motor and propeller fabrication which may not be available to the designer. Recent advancements in commercially available electric motors and propellers allows for cost effective propulsion systems. The design space selection of motors and propellers has recently increased due to component demand of remote control airplane and boats. The issue with such systems is how to predict small propeller and small motor performance interactions since remote control motor and propeller designers usually donâ t provide enough information about the performance of their product.
The mission statement is to design a propeller and motor combination that will allow an autonomous underwater vehicle to travel large distances while maintaining good efficiency. The vehicle will require 12 N of thrust with a forward velocity of 2 m/s. The propeller needs to be larger than 2.5â due to inflow velocity interaction and smaller than 4â due to loss of thrust when in surface transit due to suction.Master of Science
36
Nord, Thomas. "Voltage Stability in an Electric Propulsion System for Ships." Thesis, KTH, Elektriska energisystem, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-118932.
Full textAbstract:
This Master of Science thesis was written based on the shipbuilder Kockums AB feasibility study regarding the development of an All- Electric Ship for the Swedish Navy. The thesis was aiming at addressing voltage stability issues in a dc system fed by PWM rectifiers operating in parallel when supplying constant power loads. A basic computer model was developed for investigating the influence from various parameters on the system. It was shown that the voltage stability is dependent upon the ability to store energy in large capacitors. It was also shown that a voltage droop must be implemented maintaining load sharing within acceptable limits. Different cases of operation were modelled, faults were discussed, and the principal behaviour of the system during a short-circuit was investigated. It was shown that the short-circuit current is much more limited in this type of system in comparison to an ac system. It was concluded that more research and development regarding the components of the system must be performed.
37
Linder, Johan. "An integrated brake disc and electric drive for vehicle propulsion : A FEASIBILITY STUDY." Thesis, KTH, Skolan för elektro- och systemteknik (EES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187652.
Full textAbstract:
In this thesis, the feasibility to integrate an brake disc and electric machine is investigated. In wheel motors (IWMs) have several advantages, such as saving space in the vehicle, individual and direct control at the wheels and the absence of a mechanical transmission. However, today’s IWMs are heavy and, thus, negatively affect the driving performance of the vehicle due to the increase of the unsprung mass. By integrating an already existing part in the wheel, this increase of the unsprung mass can be minimized. The brake disc manages high temperatures, a significant wear in rough environ-ment, which puts high demands on the rotor. The second part of the machine, the stator, will be significantly affected by the high temperatures of the rotor. The temperatures of the stator are transferred by convection, conduction and radiation from the rotor or brake disc. Liquid cooling of the stator back is analyzed as a potential solution for handling the high temperatures. In order to analyze the feasibility of the concept, thermal, electric and mechanical modelling has been used. The evaluation whether it is possible or not to integrate the brake disc has been with regard to the results of weight, cost, thermal tolerance and electric performance.I detta arbete undersöks möjligheten att integrera en bromsskiva med elmaskin. Hjul-motorer har flera fördelar, bland annat sparas utrymme i själva bilen, individuell kontroll samt drivning av hjulen utan mekaniska transmissioner. Men hjulmotorer som kan användas idag väger oftast så pass mycket att den odämpade massan ökar kritiskt och köregenskaper av fordonet då blir lidande. Genom att integrera en befintlig del i hjulet kan ¨okningen av odämpade massan minskas. Att använda bromsskivan som rotor, kräver att denna tål temperaturer ¨over 500◦C samt påfrestningar och slitage som en vanlig mekanisk friktionsbroms måste uthärda. Den andra delen av maskinen, statorn kommer även denna att påverkas av de höga temperaturerna av bromsskivan som kommer ledas via konvektion, konduktion och strålning. Möjligheten att kyla statorn med vätska och om detta är tillräckligt undersöks. För att analyserna genomförbarheten av projektet har termiska, elektriska och mekaniska modeller använts. Resultaten har analyserats där maskinens vikt, kostnad, termisk tålighet och elektrisk prestanda har legat till grund för bedömningen om lösningen; att integrera en broms-skiva med elmaskin är rimlig eller ej.
38
Rousselle, Melaine. "Impact of the Electric Vehicle on the Electric System." Thesis, KTH, Elektriska energisystem, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119235.
Full textAbstract:
Since few years the electric vehicles draw the attention. The battery technology’s continual improvements and incentives from the authorities guarantee them an assured future with a fast and considerable development. Some figures are forecasted by 2020: one or two millions electric vehicles. This could mean a huge increase in electricity consumption. The consequences on the total energy consumption have already been analyzed, however studies on the impact on the load curve remain scarce. In this context, this master thesis focuses on the impact of the electric vehicles’ charge on the French load curve and the production and consumption balancing. The grid issues are not studied here. The first part presents the state of the art in battery and electric vehicle technology, as well as battery charge’s characteristics. Besides the French traffic data are studied, in order to build the most realistic model as possible. The second part explains the principle of the modeling. A general and flexible model for the French fleet is built. This model can simulate the times of charge of a vehicle, and the state of charge of its battery, in order to get a total load curve for several days for an electric fleet. And finally, the different load curves are analyzed as well as their impacts on the electric balancing system and the possible solutions to lower these impacts. As the peak load for the electric vehicles’ charge corresponds to the total consumption peak in the evening according to the most probable scenario, services have to be implemented to reduce or put back the overload due to the electric vehicles. Those services (tariff signals regulations, battery management system, cut-off injunctions) have been tested. A model for grid injections during peak hours has also been developed, in order to help the electric system, and erase the electric vehicles’ impact on the load curve. Studies for the optimum load, the reserves and the margins are also suggested as well as other possible studies, such as EV’s carbon footprint. The reflections and strategies developed in this master thesis don’t reflect RTE’s policy and don’t commit the company.
39
Dreier, Dennis. "Assessing the potential of fuel saving and emissions reduction of the bus rapid transit system in Curitiba, Brazil." Thesis, KTH, Energi och klimatstudier, ECS, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-176398.
Full textAbstract:
The transport sector contributes significantly to global energy use and emissions due to its traditional dependency on fossil fuels. Climate change, security of energy supply and increasing mobility demand is mobilising governments around the challenges of sustainable transport. Immediate opportunities to reduce emissions exist through the adoption of new bus technologies, e.g. advanced powertrains. This thesis analysed energy use and carbon dioxide (CO2) emissions of conventional, hybrid-electric, and plug-in hybrid-electric city buses including two-axle, articulated, and biarticulated chassis types (A total of 6 bus types) for the operation phase (Tank-to-Wheel) in Curitiba, Brazil. The systems analysis tool – Advanced Vehicle Simulator (ADVISOR) and a carbon balance method were applied. Seven bus routes and six operation times for each (i.e. 42 driving cycles) are considered based on real-world data. The results show that hybrid-electric and plug-in hybrid-electric two-axle city buses consume 30% and 58% less energy per distance (MJ/km) compared to a conventional two-axle city bus (i.e. 17.46 MJ/km). Additionally, the energy use per passenger-distance (MJ/pkm) of a conventional biarticulated city bus amounts to 0.22 MJ/pkm, which is 41% and 24% lower compared to conventional and hybrid-electric two-axle city buses, respectively. This is mainly due to the former’s large passenger carrying capacity. Large passenger carrying capacities can reduce energy use (MJ/pkm) if the occupancy rate of the city bus is sufficient high. Bus routes with fewer stops decrease energy use by 10-26% depending on the city bus, because of reductions in losses from acceleration and braking. The CO2 emissions are linearly proportional to the estimated energy use following from the carbon balance method, e.g. CO2 emissions for a conventional two-axle city bus amount to 1299 g/km. Further results show that energy use of city bus operation depends on the operation time due to different traffic conditions and driving cycle characteristics. An additional analysis shows that energy use estimations can vary strongly between considered driving cycles from real-world data. The study concludes that advanced powertrains with electric drive capabilities, large passenger carrying capacities and bus routes with a fewer number of bus stops are beneficial in terms of reducing energy use and CO2 emissions of city bus operation in Curitiba.
40
Lee, Jeongwoo. "Rotating Inertia Impact on Propulsion and Regenerative Braking for Electric Motor Driven Vehicles." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/30803.
Full textAbstract:
A vehicle has several rotating components such as a traction electric motor, the driveline, and the wheels and tires. The rotating inertia of these components is important in vehicle performance analyses. However, in many studies, the rotating inertias are typically lumped into an equivalent inertial mass to simplify the analysis, making it difficult to investigate the effect of those components and losses for vehicle energy use. In this study, a backward-tracking model from the wheels and tires to the power source (battery or fuel cell) is developed to estimate the effect of rotating inertias for each component during propulsion and regenerative braking of a vehicle. This paper presents the effect of rotating inertias on the power and energy for propulsion and regenerative braking for two-wheel drive (either front or rear) and all-wheel drive (AWD) cases. On-road driving and dynamometer tests are different since only one axle (two wheels) is rotating in the latter case, instead of two axles (four wheels). The differences between an on-road test and a dynamometer test are estimated using the developed model. The results show that the rotating inertias can contribute a significant fraction (8 -13 %) of the energy recovered during deceleration due to the relatively lower losses of rotating components compared to vehicle inertia, where a large fraction is dissipated in friction braking. In a dynamometer test, the amount of energy captured from available energy in wheel/tire assemblies is slightly less than that of the AWD case in on-road test. The total regenerative brake energy capture is significantly higher (> 70 %) for a FWD vehicle on a dynamometer compared to an on-road case. The rest of inertial energy is lost by inefficiencies in components, regenerative brake fraction, and friction braking on the un-driven axle.Master of Science
41
Azzeh, Abdel Rahman. "CAN Control System for an Electric Vehicle." Thesis, University of Canterbury. Electrical and Computer Engineering, 2007. http://hdl.handle.net/10092/1127.
Full textAbstract:
The University of Canterbury has purchased a 1992 Toyota MR2 and used it as the platform to construct a new electric car. Similar to the common combustion engine vehicle, electric vehicles require control systems to control the operation of 12Vdc auxiliary loads, such as lights, indicators and windscreen wipers, where traditional technology results in a large number of wires in the wiring harness. Also, with the added complexity of modern vehicles, the need for integrating independent control systems together has become very important in providing safer and more efficient vehicles. To reduce the number of wires and make it possible for different control systems to communicate, and so perform more complex tasks, a flexible and reliable control system is used. The CAN (Controller Area Network) control system is a simple two-wire differential serial bus system, which was developed by Bosch for automotive applications in the early 1980s. The power and control system within the vehicle is named the "Power Distribution Network" and it is implemented by using multiple power converters and the CAN control system. This thesis presents the design, implementation, and test results of the CAN control system for the MR2. The 312Vdc nominal battery voltage is converted to an intermediate voltage of 48Vdc. This configuration is considered more efficient than the usual 12Vdc distribution system since smaller and lighter wires can be used to carry the same amount of power. The power distribution network operates off the 48Vdc intermediate voltage, and provides 12Vdc output to power all auxiliaries within the vehicle. The Power Distribution Network is implemented with two major subsystems: the auxiliary power system, which consists of multiple converters to step-down voltage from the 48Vdc intermediate voltage to the 12Vdc, and the CAN control system, which is developed to control and integrate the 12Vdc auxiliary loads within the vehicle. The prototype CAN control system is fully operational and has been tested with 12Vdc loads which are used to simulate most of the auxiliary loads in the vehicle. Experimental measurements show that the prototype is able to successfully control and maintain the network of independent nodes. This confirms that in principle the CAN control system is suitable for controlling the auxiliary loads in an electric vehicle.
42
Hsieh, Ming-Kuang (Leo). "A Battery Equalisation System for Electric Vehicle." Thesis, University of Canterbury. Electrical and Computer Engineering, 2007. http://hdl.handle.net/10092/1172.
Full textAbstract:
Abstract In 1999, the Electrical and Computer Engineering Department at the University of Canterbury started building their third electric vehicle (EV3) based on a TOYOTA MR2 with the goal of building a higher performance vehicle to match present combustion engined vehicles. The car is powered by 26 12volt sealed lead-acid batteries connected in series to achieve a nominal 312V DC source. A battery voltage equaliser is a device that draws energy from a higher charged battery, then discharges into a lower charged battery. The need for a voltage equaliser is principally due to the differences in cell chemistry, temperature gradients along the battery string and the ages of the batteries. During the charging or discharging process, some batteries reach their nominal voltage or reach deep discharge states before the others. Then if the charger keeps charging the batteries or the load keeps drawing energy from these batteries, it results in damage to the batteries. Therefore maintaining the charge level on each battery becomes important. In addition, it also improves the battery life and vehicle travelling range. This thesis details the analysis of three different types of battery equaliser, which are based on a 24W buck-boost converter, 192W buck-boost converter and 192W flyback converter. In this design, all converters are designed to work under current mode control with average of 2A. To make each converter install without significant effect on the performance and the cost, each converter is also built with the goals of being small, lightweight, cost effective, flexible for mounting, maintenance free and highly efficient. At the end, the prototype battery equalisation converters were designed, constructed and tested, and the efficiencies from each converter are measured around 90 ~ 92%. The experimental results show two banks of series connected batteries can be successfully equalised by the designed equaliser. This thesis covers the design, simulation and the construction procedures of this battery equaliser system, and also details on some considerations and possible future improvement that were found during the experimental test.
43
Biondani, Luca. "Control system for agricultural autonomous electric vehicle." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
Find full textAbstract:
The subject of this thesis is the realization of the control system of an autonomous electric vehicle for agricultural applications. The robot will be used for field experimentation of innovative agricultural techniques.
The software is developed in LabVIEW programming language, and is employed on an embedded system manufactured by National Instruments that is used as Platform Control Unit. MATLAB and Simulink software are used for simulations and processing of the collected experimental data.
As a secondary activity, the electrical circuit was realized including both high-power and signal control wiring harness.
The result of the thesis is a working prototype that will be used in a first section of the experimental plant, located at the DISTAL Experimental Center in Cadriano.
44
Krolak, Matthew Joseph. "Optimization of a magnetoplasmadynamic arc thruster." Link to electronic thesis, 2007. http://www.wpi.edu/Pubs/ETD/Available/etd-042607-155701/.
Full text
45
Karunarathne, Lakmal. "An intelligent power management system for unmanned aerial vehicle propulsion applications." Thesis, Cranfield University, 2012. http://dspace.lib.cranfield.ac.uk/handle/1826/8038.
Full textAbstract:
Electric powered Unmanned Aerial Vehicles (UAVs) have emerged as a promi- nent aviation concept due to the advantageous such as stealth operation and zero emission. In addition, fuel cell powered electric UAVs are more attrac- tive as a result of the long endurance capability of the propulsion system. This dissertation investigates novel power management architecture for fuel cell and battery powered unmanned aerial vehicle propulsion application. The research work focused on the development of a power management system to control the hybrid electric propulsion system whilst optimizing the fuel cell air supplying system performances. The multiple power sources hybridization is a control challenge associated with the power management decisions and their implementation in the power electronic interface. In most applications, the propulsion power distribu- tion is controlled by using the regulated power converting devices such as unidirectional and bidirectional converters. The amount of power shared with the each power source is depended on the power and energy capacities of the device. In this research, a power management system is developed for polymer exchange membrane fuel cell and Lithium-Ion battery based hybrid electric propulsion system for an UAV propulsion application. Ini- tially, the UAV propulsion power requirements during the take-off, climb, endurance, cruising and maximum velocity are determined. A power man- agement algorithm is developed based on the UAV propulsion power re- quirement and the battery power capacity. Three power states are intro- duced in the power management system called Start-up power state, High power state and Charging power state. The each power state consists of the power management sequences to distribute the load power between the battery and the fuel cell system. A power electronic interface is developed Electric powered Unmanned Aerial Vehicles (UAVs) have emerged as a promi- nent aviation concept due to the advantageous such as stealth operation and zero emission. In addition, fuel cell powered electric UAVs are more attrac- tive as a result of the long endurance capability of the propulsion system. This dissertation investigates novel power management architecture for fuel cell and battery powered unmanned aerial vehicle propulsion application. The research work focused on the development of a power management system to control the hybrid electric propulsion system whilst optimizing the fuel cell air supplying system performances. The multiple power sources hybridization is a control challenge associated with the power management decisions and their implementation in the power electronic interface. In most applications, the propulsion power distribu- tion is controlled by using the regulated power converting devices such as unidirectional and bidirectional converters. The amount of power shared with the each power source is depended on the power and energy capacities of the device. In this research, a power management system is developed for polymer exchange membrane fuel cell and Lithium-Ion battery based hybrid electric propulsion system for an UAV propulsion application. Ini- tially, the UAV propulsion power requirements during the take-off, climb, endurance, cruising and maximum velocity are determined. A power man- agement algorithm is developed based on the UAV propulsion power re- quirement and the battery power capacity. Three power states are intro- duced in the power management system called Start-up power state, High power state and Charging power state. The each power state consists of the power management sequences to distribute the load power between the battery and the fuel cell system. A power electronic interface is developed with a unidirectional converter and a bidirectional converter to integrate the fuel cell system and the battery into the propulsion motor drive. The main objective of the power management system is to obtain the controlled fuel cell current profile as a performance variable. The relationship between the fuel cell current and the fuel cell air supplying system compressor power is investigated and a referenced model is developed to obtain the optimum compressor power as a function of the fuel cell current. An adaptive controller is introduced to optimize the fuel cell air supplying system performances based on the referenced model. The adaptive neuro-fuzzy inference system based controller dynamically adapts the actual compressor operating power into the optimum value defined in the reference model. The online learning and training capabilities of the adaptive controller identify the nonlinear variations of the fuel cell current and generate a control signal for the compressor motor voltage to optimize the fuel cell air supplying system performances. The hybrid electric power system and the power management system were developed in real time environment and practical tests were conducted to validate the simulation results.
46
Sato, Sho Ph D. Massachusetts Institute of Technology. "Design and characterization of Hover Nano Aerial Vehicle (HNAV) propulsion system." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/44925.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2008.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 321).
On October 4th 2005, DARPA released a request for proposals for a Nano-Air Vehicle (NAV) program. The program sought to develop an advanced urban reconnaissance vehicle. According the requirement imposed by DARPA, the NAV was to have dimensions smaller than 7.5 cm in diameter, and a weight of approximately 10 grams, to allow indoor operation. On top of these requirements, this vehicle was to operate for about 20 minutes, and have a low noise signature to avoid risk of detection. This thesis addresses the propulsion system required to enable the DARPA NAV. In particular, a rotary-wing vehicle is favored because of its high efficiency and simplicity. One large challenge faced for this design is the torque canceling mechanism to counter the torque produced by the rotating rotor. To provide a reasonable torque canceling, the solution proposed here is to use a rotating motor inside the vehicle. One rotor will be attached to the shaft of the motor and the other to a motor body that is left free to rotate inside the vehicle. By letting the motor rotate freely inside the body, the torque is cancelled automatically without a gearbox. In addition to this passive torque canceling mechanism, a novel approach is used in the fabrication approach of the motor in order to maximize the power density of this propulsion system. This new fabrication method involves the use of flexible printed circuit for the stator of the motor, which allows for the motor to achieve high power density, while simplifying its manufacturing process. The main goal of this project is to combine these two novel approaches in order to design, fabricate and assess the performance of the proposed propulsion system design. In this thesis, a prototype propulsion system for this vehicle, featuring the new motor fabrication approach, is designed, fabricated and tested.
(cont.) Firstly, the design model required to design the main components of the propulsion system (the motor model, the propeller model, and the design optimization program) is developed. The fabrication process of the propulsion system is then established, and an operational propulsion system prototype is fabricated using the established design tools and fabrication procedure. Finally, series of experiments are conducted in order to characterize the performance of the propulsion system and to validate the model used in the design of the propulsion system. Based on the results obtained from the experiment, it is found that the motor model used in the design of the motor for the propulsion system is accurate, with an error of 5% in the prediction of output shaft power of the motor. Among various configuration tested for the propulsion system, a combination of 5-bladed propeller and 3-bladed propeller, designed around the motor operating speed of 9,000 rpm is found to be most optimal for this propulsion system, featuring the following performance:for maximum achievable thrust of 17.28 g, well beyond hover thrust required for the vehicle;for capable of providing hover thrust at a power consumption of 1.26W, which translates to an hovering endurance of approximately 20 minutes using a lithyum polymer battery chosen for the vehicle;for torque cancelling mechanism capable of cancelling up to 99% of torque generated in the motor; and for noise footprint lower than 45 dBA, a typical indoor background noise during the day, 1 m away from the propulsion system. Based on these results, it is concluded that the propulsion system developed here is capable of meeting all the requirement imposed by DARPA. Since this research does not focus on the control aspect of the vehicle, further research should be conducted in the field of control and navigation in order to achieve a fully autonomous NAV.
by Sho Sato.
S.M.
47
Petrus, Vlad. "Switched reluctance motors for electric vehicle propulsion: comparative numerical and experimental study of control schemes." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209575.
Full textAbstract:
Policies to reduce emissions from transportation are implemented by different World and Europeanassociations. Personal and freight transportation is one of the key contributors in GHG
emissions, being the second biggest GHG emitter after energy sector in the European Union.
The policies to reduce emissions from transportation are focusing on the optimization of the efficiency
of the existing vehicles, the development of new sustainable fuels and propulsion systems
and the electrification of the vehicles
The continuously increasing price of the permanent magnets and the shortage of rare earths
demand the finding of alternatives for the permanent magnet synchronous machines which is
currently the leading technology in several domains as hybrid and full electric propulsion and
wind turbines due to their best overall performances.
The good efficiency and the large constant power-speed ratio in addition to low the cost, high
reliability and fault-tolerance make the SRM a candidate with real chances on the market of
vehicle propulsion. The main drawbacks of the SRM related to the torque ripple, noise and
vibration make the research object in R&Ds all over the world.
This thesis is focused on the development of an efficient and robust switched reluctance drive
which can be integrated in a hybrid dive train or can be solely used for electric vehicle traction.
To achieve this goal, various instantaneous and average torque control techniques are implemented
and compared. A converter is designed, built and integrated on a test bench which
allows testing SRMs for vehicle propulsion. An investigation on noise production in SRDs ends
the thesis.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
48
Espinosa, Orozco Jesus. "Intake Design, and Optimization for an Atmosphere- Breathing Electric Propulsion System." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292688.
Full textAbstract:
Over the last two decades, Very Low Earth Orbit (VLEO) has gained researchers attention as it provides a significant amount of benefits in the field of earth observation and telecommunications. VLEO provides increased payload performance, improved geospatial accuracy, lower launch mass, simplified end of life disposal, and they reduce space-debris collision risk. However, the utilization of orbits with such low altitudes presents its own set of challenges, denser atmosphere will significantly increase aerodynamic drag, decaying the orbit in a short period of time. Besides increased drag VLEO environment will produce high levels of spacecraft (SC) charging and the presence of atomic oxygen will generate a constant erosion on the surfaces of the SC. An Atmosphere-Breathing Electric Propulsion (ABEP) ingests the residual atmosphere through an intake and uses it as propellant for an electric thruster. Theoretically applicable to any planet with an atmosphere, the system might allow drag compensation for an unlimited time without carrying propellant. In this thesis, different approaches for an intake are introduced, while the modeling, and numerical testing by Direct Simulation Monte Carlo (DSMC) is also presented. The intake is optimized for the RF Helicon-based Plasma Thruster (IPT) developed at IRS and a new concept design takes advantage of new materials properties, for specular surface interactions. Simulation results over different altitudes and conditions used for the verification of the design have been performed achieving a maximum collection efficiency of 94%.Under de senaste två decennierna har “Very Low Earth Orbit“ VLEO fått stor uppmärksamhet inom forskningsvärlden då det leder till en mängd fördelar inom jordobservation och telekommunikation. VLEO ger ökad nyttolastprestanda, förbättrad geospatial noggrannhet, lägre startmassa, förenklat bortförskaffande och minskning kollisionsrisken för rymdskräp. Användningen av omloppsbanor på så låg höjd medför dessvärre också utmaningar. Den lägre höjden innebär tätare atmosfär och ökar därav det aerodynamiska luftmotståndet avsevärt. Förutom ökad luftmotstånd kommer miljön i VLEO att producera höga nivåer av rymdfarkostladdning och närvaron av atomärt syre leder till en konstant erosion av farkosters ytor. En ABEP leder in den återstående atmosfären genom ett intag och använder den som drivmedel för en elektrisk drivraket. Teoretiskt tillämpbart på alla planeter med en atmosfär, kan systemet tillåta luftmotståndskompensation under obegränsad tid utan något annat drivmedel än den redan befintliga atmosfären. I denna avhandling presenteras olika modeller för ett intag samtidigt som modellering och numerisk testning av DSMC också presenteras. Intaget optimeras för den IPT som utvecklats vid IRS och en ny konceptdesign utnyttjar nya materialegenskaper för speciella ytinteraktioner. Simuleringsresultat över olika höjder och förhållanden som används för verifiering av designen har utförts och resulterat i en maximal insamlingseffektivitet på 94%.
In den letzten zwei Jahrzenten gewann die tiefe Erdumlaufbahn “Very Low Earth Orbit“ (VLEO) durch die erheblichen Vorteile für Erdbeobachtung und Telekommunikation an Aufmerksamkeit in der Wissenschaft. VLEO ermöglicht eine höhere Nutzlastleistung, verbesserte räumliche Genauigkeit, eine geringere Startmasse, vereinfachte “End-of-Life“ - Entsorgung und verringert das Kollisionsrisiko von Weltraumschrott. Die Nutzung von Umlaufbahnen in diesen geringen Höhen stellt jedoch auch eine Reihe von Herausforderungen dar. Die dichtere Atmosphäre im VLEO erhöht den Luftwiderstand erheblich und verringert die Umlaufbahn in kurzer Zeit. Neben dem erhöhten Luftwiderstand tritt auch hohe Raumschiff- oder Satellitenladung auf und durch atomaren Sauerstoff entsteht konstante Erosion an den Oberflächen. Ein atmosphärenatmender elektrischer Antrieb (ABEP) nimmt die Restatmosphäre über einen Einlass auf und verwendet sie als Treibstoff für ein elektrisches Triebwerk. Theoretisch auf jeden Planeten mit Atmosphäre anwendbar, könnte das System so den Widerstand zeitlich unbefristet ohne Treibstoffverwendung kompensieren. In dieser Arbeit werden verschiedene Ansätze für einen Einlass vorgestellt, und die Modellierung und numerischen Tests durch die “Direct Simulation Monte Carlo“ (DSMC) werden präsentiert. Der Einlass ist für den am IRS entwickelten RF Helicon-basierten Plasma Thruster (IPT) optimiert. Ein neues Konzeptdesign nutzt neue Materialeigenschaften für spiegelartige Oberflächen-Reflektionseigenschaften. Simulationsergebnisse verschiedener Höhen und Konditionen wurden zu der Überprüfung des Entwurfs verwendet, wobei eine maximale Einlassammlungswirkungsgrad von 94% erreicht wurde.
49
Zwahlen, Jurg C. "Investigation or a pulsed plasma thruster plume using a quadruple Langmuir probe technique." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0108103-143841.
Full text
50
Ahmad, Mazlan Ahmad Naddi. "A fully actuated tail propulsion system for a biomimetic autonomous underwater vehicle." Thesis, University of Glasgow, 2015. http://theses.gla.ac.uk/6343/.
Full textAbstract:
In recent years that has been a worldwide increase in the utilisation of Autonomous Underwater Vehicles (AUVs) for many diverse subsea applications. This has given rise to an increase in the research and development of these vehicles, with a particular focus on extending operational capability and longevity. Consequently, this activity has resulted in the design of many different types of AUVs that employ a variety of different propulsion and manoeuvring mechanisms. One particular area that has yielded promising results involves the vehicles designs that are biologically inspired or biomimetic. This class of AUV replicates the anatomical features of aquatic species in order to exploit some of the benefits associated with this type of swimming e.g. higher efficiency at low speeds, improved manoeuvrability. The study presented in this thesis considers the design and performance analysis of a unique biomimetic AUV design based on the physiology of an adult Atlantic salmon. This vehicle, called RoboSalmon, is equipped with a multiple jointed, fully actuated tail that is used to replicate the undulatory swimming gait of a real fish. The initial stage of this design process involves the development of a mathematical model to describe the fusion of the dynamics and electro-mechanics of this vehicle. This model provides the design specifications for a prototype vehicle, which has been used in water tank trials to collect data. Forward swimming and manoeuvring experiments, e.g. cruise in turning and turning circle swimming patterns, have been conducted for performance analysis and validation purposes. This part of the study has illustrated the relationship between the vehicle surge velocity, tail amplitude and tail beat frequency. It was found that the maximum surge velocity has been measured at 0.143 ms-1. Also, the vehicle has been shown to accomplish turning circle manoeuvres with turning radius just over the half of its body length. The final stage of this study involved the design of a heading control system, which changes the course of the vehicle by altering the tail centreline. This study allowed the course changing performance of the vehicle to be analysed. Furthermore, a line of sight guidance system has been used to navigate the vehicle through a multiple waypoint course in order to show autonomous operation within a simulated environment. Moreover, the vehicle has demonstrated satisfactory performance in course changing and tracking operations. It is concluded that the RoboSalmon biomimetic AUV exhibits higher propulsive efficiency and manoeuvrability than propeller based underwater vehicles at low speeds. Thus the results of this study show that mimicking biology can improve the propulsive and manoeuvring efficiencies of AUVs.