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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
401

Intérêt d’une Source d’Energie Electrique Hybride pour véhicule électrique urbain – dimensionnement et tests de cyclage / Interest of a hybrid electric energy storage for an urban electric vehicle - sizing and lifetime tests

Sadoun, Redha 03 June 2013 (has links)
Actuellement, la principale source d’énergie embarquée dans les véhicules électriques est composée de batteries Li-ion. Cette thèse fait partie des thématiques communes de travail que mène L’ESTACA en collaboration avec le L2EP. L’objectif ce projet est d’étudier l’apport d’une source hybride composée de batteries Li-ion et des supercondensateurs, sur les performances d’un véhicule électrique urbain.Dans un premier temps, une stratégie de gestion d’energie basée sur l’approche des règles déterministes a été appliquée pour montrer l’intérêt de l’association des différentes technologies de batterie Li-ion (haute puissance, haute énergie) avec le supercondensateur en fonction de l’autonomie voulue. Cette étude nous a permis de proposer une solution optimale (poids, volume, coût..) composée d’une batterie énergétique et un supercondensateur.Dans la deuxième partie, on a suivie l’évolution du vieillissement des deux de deux batteries de type haute puissance et hautes énergie dans, respectivement, les configurations mono-source et hybride. Pour réaliser cette étude, un banc de tests, destiné au cyclage et la caractérisation des systèmes de stockage, a été utilisé. Les résultats obtenus, offriront la possibilité de se prononcer sur le type de batteries Li-ion qui pourrait être le plus intéressant pour l’alimentation des véhicules électriques / Currently, the main embedded storage system supplying the electric vehicles is composed of Li-ion batteries. This thesis is one of the common themes of work that ESTACA leads in collaboration with L2EP. The objective of this work is to study the interest of a hybrid source composed of Li-ion batteries and supercapacitors to supply an urban electric.Firstly, an energy management strategy based on deterministic rules is developed to control the power between the battery and supercapacitor. To demonstrate the combination utility, different Li-ion battery technologies (Li-ion high power, high-Li-ion energy) are used on the sizing step. Through this study, we could propose an optimal solution (masses, volumes, costs...) consisting of battery and supercapacitor. In the second part, we have followed the evolution of capacity and the internal resistance losses of high power and high energy batteries type in, respectively, single-source and hybrid configurations. For this study, a test bench, developed for cycling and characterization of storage systems, was used. The results obtained provide the opportunity to choose Li-ion battery technology that could be the most interesting for the supply of electric vehicles
402

Convertisseur haut rendement à dimensionnement réduit pour batterie hybridée puissance/énergie de véhicule électrique : Principe de source de courant contrôlée / Reduced sizing converter for hybrid batteries power / energy of electric vehicle : Controlled current source principle

Allali, Nicolas 12 December 2016 (has links)
Ce mémoire présente une solution de conversion d’énergie permettant de couplerdeux sources de tension électrique similaire à dimensionnement réduit. Appliqué à un système de stockage hybridé puissance/énergie pour véhicule électrique, cette solution présente un compromis de coût de production, de masse et de rendement énergétique meilleur que celui des hacheurs classiques. Nous proposons en réponse à cette problématique l’utilisation d’une source de courant contrôlée placée en série avec les deux sources de tension pour réaliser leur couplage. Une structure de convertisseur permettant ce couplage est étudiée, puis comparée à une structure classique, et enfin réalisée au travers d’un démonstrateur à échelle de tension réduite afin de mettre en évidence ses avantages et inconvénients / This thesis deals with the development of a power conversion solution, allowing for the coupling of two similar voltage sources. Applied to a combined battery storage sys-tem power/energy for electric vehicles, the proposed solution presents a compromise between production costs, mass and energy performance, providing a better solution than those currently in existence. As such, the two voltage sources are coupled in series with a controlled current source. A structure of the converter allowing the coupling is studied and compared to a classic structure. Finally a demonstrator on a reduced voltage scale has been realized and shows advantages of this converter solution.
403

Conception par optimisation d'une chaine de traction électrique et de son contrôle par modélisation multi-physique / Optimal design of an electric powertrain with its control through multi-physics modeling

Caillard, Pierre 13 November 2015 (has links)
Les travaux de cette thèse portent sur la méthodologie de conception par optimisation d’une chaine de traction de véhicule électrique en phase amont du développement. Dan une première partie, nous avons abordé le contexte environnemental du transport afin d poser la problématique de la conception systémique d’une chaine de traction électrique composée d’une transmission, une machine électrique asynchrone, un onduleur et un batterie. Le cas test est celui du Renault Twizy. La seconde partie explore les possibilité de modélisation puis détaille les modèles analytiques qui ont été choisis pour chaque composant. L’assemblage de ces modèles permet une estimation de l’autonomie d véhicule, au travers du calcul des pertes des composants, et du cout de la chaine d traction. La troisième partie est consacrée aux méthodes et stratégies d’optimisation afin d pouvoir exploiter le modèle système en incluant le cycle de roulage, le contrôle de l machine électrique et les différentes physiques des composants, tout en conservant de temps de calcul raisonnable. Enfin, la dernière partie présente des résultats d’optimisation en comparant différents jeux de variables et objectifs, soulignant l’importance d’un conception systémique. Des essais sur banc permettent de valider les hypothèses qui on été posées / The works of this thesis concern the optimal design methodology of an electric vehicl powertrain, in early development phase. The first part of this report introduces th environmental context of transportation in order to assess the problem of system design o an electric powertrain which includes a transmission, an induction machine, an inverter an a battery. The selected study case is a Renault Twizy. The second part deals with modelin choices and details the analytic models of the components. Then these models are pu together to get an estimate of the vehicle range, by calculating the components’ losses an the powertrain cost. The third part is devoted to methods and optimization strategies wit the objective to use the systemic model with driving cycles, electric machine control and th physics of each component, without increasing too much computing times. The final par presents results from optimal designs, by comparing several variables or objectives sets Results show how significant the systemic design is. Experiments on a test bench allow validating the hypothesis that have been made
404

A Novel Hybrid Vehicle Architecture : Modeling, Simulation and Experiments

Chanumolu, Raviteja January 2017 (has links) (PDF)
Electric and hybrid vehicles are particularly suited for use in urban areas since city transportation is mainly characterized by relatively short driving distances, low continuous power requirements, long idling times and high availability of regenerative braking energy. These characteristics, when carefully incorporated into the design process, create valuable opportunities for developing clean, efficient and cost effective urban vehicle propulsion systems. In the first part of the thesis, we present data collected in the city of Bangalore, India from a very commonly seen mode of transportation for hire in India and other emerging economies, namely a three-wheeled vehicle known as the “auto-rickshaw”. From a statistical analysis, it is shown that the typical range is 72.5 km with a mean speed of 12.5 km/h. More than 60% of the time the auto-rickshaw is stationary or has a speed of less than 5 km/h. From a model of the auto-rickshaw, it is shown from simulations that 4 kW DC motor and about 10 kWh of electrical energy is enough to meet 80% of typical requirement. Based on this finding, in this thesis, a novel parallel hybrid architecture is proposed where two 2 kW DC hub motors are directly mounted on the wheels and an internal combustion (IC) engine output is connected to the stator of the DC hub motors to provide additional power when required. To match load and speed, a continuously variable transmission (CVT) is placed in-between the IC engine and the DC hub motor. The proposed hybrid configuration adds speed to the wheel output unlike the normal power split configuration which adds torque. One of the main objective of this work is to study and compare the performance of the above novel speed-addition and compare with the typical torque-addition configuration. A MATLAB/Simulink model for both the configurations, with DC hub motor and a small IC engine, has been created and the fuel consumption has been calculated. It is shown that the proposed speed-addition concept gives better fuel efficiency for the standard modified Indian Driving Cycle. The models have also been compared for actual driving data and an optimal control strategy has been developed using dynamic programming. It is again shown that the proposed speed-addition concept results in better fuel economy. In the last part of the thesis, a low cost experimental test-bed consisting of an auto-rickshaw IC engine, a CVT and a 2 kW DC hub motor has been developed to validate the speed-addition concept and compare with the torque-addition configuration. The torque-speed curves of the IC engine, the DC motor and both of them together, in the speed and torque-addition configuration, have been obtained. It is shown that the speed-addition concept does indeed work and the obtained results are significantly different from the torque-addition configuration.
405

Switched reluctance motors for electric vehicle propulsion: comparative numerical and experimental study of control schemes

Petrus, Vlad 21 September 2012 (has links)
Policies to reduce emissions from transportation are implemented by different World and European<p>associations. Personal and freight transportation is one of the key contributors in GHG<p>emissions, being the second biggest GHG emitter after energy sector in the European Union.<p>The policies to reduce emissions from transportation are focusing on the optimization of the efficiency<p>of the existing vehicles, the development of new sustainable fuels and propulsion systems<p>and the electrification of the vehicles<p>The continuously increasing price of the permanent magnets and the shortage of rare earths<p>demand the finding of alternatives for the permanent magnet synchronous machines which is<p>currently the leading technology in several domains as hybrid and full electric propulsion and<p>wind turbines due to their best overall performances.<p>The good efficiency and the large constant power-speed ratio in addition to low the cost, high<p>reliability and fault-tolerance make the SRM a candidate with real chances on the market of<p>vehicle propulsion. The main drawbacks of the SRM related to the torque ripple, noise and<p>vibration make the research object in R&Ds all over the world.<p>This thesis is focused on the development of an efficient and robust switched reluctance drive<p>which can be integrated in a hybrid dive train or can be solely used for electric vehicle traction.<p>To achieve this goal, various instantaneous and average torque control techniques are implemented<p>and compared. A converter is designed, built and integrated on a test bench which<p>allows testing SRMs for vehicle propulsion. An investigation on noise production in SRDs ends<p>the thesis. / Doctorat en Sciences de l'ingénieur / info:eu-repo/semantics/nonPublished
406

Effective simulation model and new control strategy to improve energy efficiency in hybrid electric land vehicle / Modèle de simulation efficace et nouvelle stratégie de contrôle pour améliorer l'efficacité énergétique dans les véhicules hybrides électriques terrestres

Asus, Zainab 16 December 2014 (has links)
Les principaux objectifs de ce travail est de développer une méthode de modélisation efficace pour un déploiement facile et rapide d'une stratégie de contrôle, d'examiner et d'étudier cette stratégie pour une application spécifique, et d'analyser l'amélioration qui peut être apporté à un moteur pour une meilleure efficacité dans les systèmes électrique et hybride. Ce travail comprend une partie simulation du système étudié et sa validation avec les résultats expérimentaux. Les études de cas sont utilisées pour analyser l'optimisation qui peut être effectuée en comparaison au système d'origine (le véhicule étudié est la NOAO).Un outil d'optimisation est choisie pour optimiser la stratégie de contrôle actuellement déployée sur le véhicule. Cette outil nous a permis de développer une nouvelle stratégie de commande optimisée prêt à être déployé dans le véhicule. Un procédé de prédiction pour connaître la consommation d'énergie du système est mis au point en vue d'obtenir un contrôle optimal adapté à la demande du véhicule et à une utilisation spécifique.Comme perspectives, les principaux composants du système peuvent être étudiés et modélisé afin d'améliorer l’efficacité énergétique du véhicule. La Représentation Energétique Macroscopique (REM) est une bonne méthode pour représenter le modèle dynamique et peut être utilisé pour modéliser des machines électromécaniques. Cette méthode est également envisagé pour modéliser d’autre système que le système véhicule tel que les systèmes énergies renouvelables, les systèmes électromécanique ou robotique. / The main objectives of this work is to develop an effective modeling method for an easydeployment of a control strategy, to review and study an optimal control strategy for a specific application, and to analyze improvement that can be effected to engine for better efficiency in hybrid vehicle architecture. The scopes of this work include the simulation part of the studied system and its validation with experimental results. Study cases are used to analyze optimization that can be effected to the original system. A well established optimization tool is chosen to optimize the actual control strategy and becomes a benchmark of a new optimal control strategy to be deployed in the system. A predictive method to know energy consumption of the system is developed in order to obtain an optimal control suitable with the vehicle application. Using the developed model, analysis is conducted to identify an optimal control strategy for a specific utilization. As perspectives, the main components of the system can be studied for improvements of its energy efficiency. The Energetic Macroscopic Representation (EMR) is a good method to represent dynamic model and it can be used to model any electromechanical machines and can be envisaged to model other system than a vehicle system, like a renewable energy system, a new electro-mechanical system or a robotic system.
407

Development of aqueous ion-intercalation battery systems for high power and bulk energy storage

Key, Julian D.V. January 2013 (has links)
Philosophiae Doctor - PhD / Aqueous ion-intercalation batteries (AIB’s) have the potential to provide both high power for hybrid-electric transport, and low cost bulk energy storage for electric grid supply. However, a major setback to AIB development is the instability of suitable ionintercalation anode material in aqueous electrolyte. To counter this problem, the use of activated carbon (AC) (a supercapacitor anode) paired against the low cost ionintercalation cathode spinel LiMn2O4 (LMO) provides a stable alternative. This thesis comprises two novel areas of investigation concerning: (1) the development of the AC/LMO cell for high power applications, and (2) the introduction of PbSO4 as a high capacity alternative anode material paired against LMO for low cost bulk energy storage. The study on AC/LMO explores the electrode combination’s practical specific energy and power capability at high P/E (power to energy ratio) of 50:1 suitable for hybrid electric vehicle batteries. To study the relationship between electrode material loading density, active material performance, and current collector mass contribution, a specially designed cell was constructed for galvanic cycling of different thicknesses of electrode. Between a loading density range of 25 – 100 mg, ~50 mg of total active material between two 1 cm2 current collectors produced the highest 50:1 P/E ratio values of 4 Wh/kg and 200 W/kg, constituting a 4-fold reduction of the active material values of thin films at 50:1 P/E. The cycling potentials of the individual electrodes revealed that doublings of electrode film loading density increased the LMO electrode’s polarization and voltage drop to similar levels as doublings in applied current density. However, by increasing the charging voltage from 1.8 V to 2.2 V, 6 Wh/kg and 300 W/kg was obtainable with minimal loss of energy efficiency. Finally a large-format cell of a calculated 3 Ah capacity at 50:1 P/E was constructed and tested. The cell produced ~60% of the anticipated capacity due to a suspected high level of resistance in the electrode contact points. The overall conclusion to the study was that AC/LMO holds promise for high power applications, and that future use of higher rate capability forms of LMO offers a promising avenue for further research. v The second part of this thesis presents the development of a novel cell chemistry, PbSO4/LMO, that has yet to be reported elsewhere in existing literature. The cell uses aqueous pH 7, 1 M, Li2SO4 electrolyte, and forms an electrode coupling where the PbSO4 anode charge/discharge is analogous to that in Pb-acid batteries. The average discharge voltage of the cell was 1.4 V and formed a flat charge/discharge plateau. The use of a low cost carbon coating method to encapsulate PbSO4 microparticles had a marked improvement on cell performance, and compared to uncoated PbSO4 improved both rate capability and specific capacity of the material. The active materials of the carbon-coated PbSO4/LMO cell produced a specific energy 51.1 Wh/kg, which, if a 65% yield is possible for a practical cell format, equals 38.4 Wh/kg, which is 15 Wh/kg higher than AC/LMO bulk storage cells at 23 Wh/kg, but lower than Pb-acid batteries at ~25-50 Wh/kg. Interestingly, the specific capacity of PbSO4 was 76 mAh/g compared to 100 mAh/g in Pb-acid cells. The predicted cost of the cell, providing a 65% value of the active material specific energy for a practical cell can be realized, is on par with Pb-acid battery technology and, importantly, uses 2.3 × less Pb/kWh. The cycling stability achieved thus far is promising, but will require testing over comparable cycle life periods to commercial batteries, which could be anywhere between 5 – 15 years.
408

Sonification des véhicules électriques par illusions auditives : étude de l'intégration audiovisuelle de la perception du mouvement automobile en simulateur de conduite / Sonifying electric vehicles with auditory illusions : A driving simulator study on the audiovisual integration of automotive motion perception

Denjean, Sebastien 16 March 2015 (has links)
Ces travaux de thèse portent sur la mise en place d’une stratégie de sonification qui vise à proposer un retour sonore pouvant se substituer au bruit moteur dans les véhicules électriques, rendant au conducteur les informations qu’il transmet habituellement sur la dynamique du véhicule.Pour cela, nous nous sommes basés sur une première phase d’analyse qui nous a permis d’étudier comment le bruit automobile influence notre perception du mouvement. A partir de deux expériences menées en simulateur de conduite, nous avons pu relier le retour sonore et la vitesse perçue par le conducteur, définissant ainsi la métaphore du bruit moteur sur laquelle s’appuie le contrôle des sons de synthèse.De façon similaire au bruit moteur, le retour sonore proposé informe le conducteur par l’intermédiaire de sa variation de hauteur tonale. Pour arriver à un son qui informe le conducteur efficacement et qui reste acceptable sur toute la gamme de vitesse du véhicule, nous nous sommes appuyés sur l’illusion de glissando infini de Shepard-Risset, qui nous permet de donner un retour d’information précis grâce à une hauteur tonale qui varie rapidement tout en restant contenue dans une plage de fréquence restreinte.L’apport de cette stratégie a enfin été testé lors de deux expériences, la première portant sur l’influence de ce retour sonore sur la perception de la vitesse des conducteurs, la seconde sur leur comportement dans une tâche de freinage. Ces deux études ont montré un effet significatif du retour sonore qui suggère que ces informations sont bien intégrées par les conducteurs, faisant de ces sons un candidat prometteur pour devenir le « bruit moteur » des véhicules de demain. / This thesis aims to build an auditory display to sonify electric vehicles. Our goal consisted in bringing back to the driver the motion information, which is usually provided by the combustion engine noise.The first stage of this work consisted in analyzing how automotive noises can influence drivers’ perception of motion. We conducted two driving simulator experiments to study drivers’ speed perception in presence of different automotive noises. These results provided a link between the acoustic feedback and the speed perceived by the driver, on which we based our sonification strategy.Similarly to combustion engine noise, the acoustic feedback proposed in this work informs the driver via its pitch variation. We used the Shepard Risset glissando illusion to sonify the whole speed range of the vehicle. Pitch circularity in the construction of these sounds provides a precise information on small speed variation with fast pitch variations, and is in addition restrained within a narrow bandwith.We then tested the contribution of this strategy in two experiments. The first dealt with the influence of the proposed sounds on drivers’ speed perception ; the second with their behavior in a common braking task. These studies showed that the drivers easily integrate the information brought by this sound, and that it influences their perception of motion and modifies their driving behavior. These inputs make the proposed sound a good candidate to become the new « engine noise » of future electric cars.
409

Impacts des modèles de pertes sur l’optimisation sur cycle d’un ensemble convertisseur – machine synchrone : applications aux véhicules hybrides / Impacts of loss models on the optimization design during driving cycle of permanent magnet synchronous machines for hybride electric vehicle applications

Nguyen, Phi-Hung 30 November 2011 (has links)
La quasi-totalité des études de machines synchrones à aimants permanents (MSAP) pour les applications aux véhicules hybrides concernent les performances uniquement sur quelques points particuliers d’un cycle de fonctionnement du véhicule (le point de base, le point à grande vitesse ou le point le plus sollicité). Cependant, ces machines électriques fonctionnent souvent à différents couples et à différentes vitesses. Cette thèse s’intéresse donc à l’étude des performances de MSAP sur l’ensemble d’un cycle de fonctionnement en vue de les optimiser sur cycle. Durant cette thèse, l’auteur a contribué à développer les modèles de couple, de défluxage, de pertes cuivre et de pertes magnétiques et les méthodes de calcul de ces pertes à vide et en charge pour les quatre MSAP dont trois machines à concentration de flux et une machine à aimants en surface du rotor et pour trois cycles de fonctionnement : NEDC, Artemis-Urbain et Artemis-Routier. Une validation expérimentale de ces modèles a été effectuée sur un banc d’essai moteur avec deux prototypes de MSAP. Ensuite, les MSAP ont été dimensionnées en vue d’une minimisation des pertes sur cycle et du courant efficace du point de base. Cette combinaison a pour but d’augmenter le rendement de la machine électrique et de minimiser la dimension de l’onduleur de tension associée. Ce problème d’optimisation multi-objectif a été réalisé en utilisant l'algorithme génétique, Non-Dominated Sorting Genetic Algorithm (NSGA-II). Ainsi, un Front de Pareto des solutions optimales peut être déduit. Les impacts des modèles de pertes (à vide et en charge) sur l’optimisation sur cycle des machines sont étudiés et l’intérêt de chaque modèle est présenté. Les modèles et méthodes de calcul proposés peuvent être appliqués à tous les cycles de fonctionnement, à différentes MSAP et à différentes applications. / Almost all studies of permanent magnet synchronous machines (PMSM) for for hybrid vehicle applications relate to their performances on a specific point of a driving cycle of the vehicle (the base point, the point at high speed or the most used point). However, these machines often operate at different torques and at different speeds. This thesis studies therefore PMSM performances in order to optimize during an entire driving cycle. In this thesis, the author contributed to develop models of torque, field weakening, copper losses and iron losses and methods of calculating these losses at no-load and at load for four MSAP (three concentrated flux machine and a surface mounted PMSM) and for three driving cycles (New Eurepean Driving Cycle, Artemis-Urban and Artemis-Road). An experimental validation of these models was realized on a test bench with two prototypes of MSAP. Then, the MSAP were sized for a minimization of average power losses during the cycle and of the RMS current at the base point. This combination is designed to increase the efficiency of the electrical machine and minimize the size of the associated voltage inverter. This problem of multi-objective optimization was performed using the genetic algorithm, Non-Dominated Sorting Genetic Algorithm (NSGA-II). Thus, a Pareto front of optimal solutions can be derived. The impacts of loss models (at no-load and at load) on the PMSM optimization during the cycle are studied and the interest of each model is presented. Models and calculation methods proposed in this thesis can be applied to all cycles, at different MSAP and for other applications.
410

DESIGN OF A HYBRID HYDROGEN-ON-DEMAND AND PRIMARY BATTERY ELECTRIC VEHICLE

Michael J Dziekan (7241471) 14 January 2021 (has links)
<p>In recent years lithium-ion battery electric vehicles and stored hydrogen electric vehicles have been developed to address the ever-present threat of climate change and global warming. These technologies have failed to achieve profitability at costs consumers are willing to bear when purchasing a vehicle. IFBattery, Inc. has developed a unique primary battery chemistry which simultaneously produces both electricity and hydrogen-on-demand while being both low cost and without carbon emissions. In order to determine the feasibility of the IFBattery chemistry for mobile applications, a prototype golf cart was constructed as the first public application of IFBattery technology. The legacy lead acid batteries of the prototype golf cart were replaced with an IFBattery chemistry tuned to primarily produce hydrogen-on-demand with supplemental electricity. Hydrogen produced by the IFBattery was purified and then fed into a hydrogen fuel cell where electricity was produced to power the vehicle. Electricity from the IFBattery was converted to the common voltage of the golf cart and also used to power the vehicle. Validation testing of the IFBattery powered golf cart demonstrated favorable results as an alternative to both lithium-ion battery and stored hydrogen technologies, and displayed potential for future applications.</p>

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