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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.
361

Market analysis for electric vehicle supply equipment : The case of China / Analys av marknaden för laddningsutrustning för elbilar : Fallet Kina

BUSK, ANDREY, JOELSSON WARRENSTEIN, ARVID January 2014 (has links)
Personliga eldrivna fordon (EV) är ett nytt teknikområde som är på väg att uppnå stort momentum på flera av världens marknader. Eftersom branschen fortfarande ligger i sin linda finns det i nuläget inga tydliga strukturer, som gäller för alla marknader världen över, gällande relationerna mellan aktörer, vilket leder till osäkerheter när det kommer till att ta strategiska beslut. Uppdragsgivaren för denna studie är Hong Kong EV Power Ltd. (EV Power), en Hongkong-baserad leverantör av laddningsstationer för elbilar och relaterade tjänster, som har ambitionen att inträda marknaden på det kinesiska fastlandet inom den närmaste framtiden. Emellertid har EV Power ännu inte bestämt sig vilken stad de vill rikta in sig på i det första skedet. Denna avhandling ämnar formulera en modell som kan användas för att utvärdera och jämföra geografiska marknader med avseende på lämpligheten för ett marknadsinträde av en leverantör av laddningsstationer för elbilar. Dessutom kommer modellen testas på tre städer på kinas fastland (Peking, Shanghai och Shenzhen), med syfte att komma fram till vilken stad som är mest attraktiv för EV Power, samt att utvärdera modellens funktionsduglighet. Sist kommer resultaten från utvärderingen av de tre städerna att tjäna som utgångspunkten för en analys som ämnar ta fram framgångsfaktorer för ett marknadsinträde på kinas fastland. För att uppnå detta har fyra olika datainsamlingsmetoder använts: Först studerades teori, med syfte att få bakgrundskunskap likväl som att få förståelse för specifika faktorer som påverkar ett marknadsinträde som detta. För det andra observerades EV Powers nuvarande verksamhet i Hong Kong, i avsikt att förstå vad som har lett till den framgång som företaget upplevt på sin hemmamarknad. För det tredje intervjuades branschexperter för att få ett perspektiv på branschen som helhet. Sist samlades sekundär data kring de tre städerna in, för att kunna utvärdera de olika faktorerna som ingår i den framtagna modellen. Den slutgiltiga modellen består av fem faktorer som påverkar en stads attraktivitet för ett marknadsinträde av en leverantör av laddningsstationer för elbilar. De identifierade faktorerna är: ’Marknadens tillgänglighet’, ’Kortsiktig efterfrågan’, ’Förväntad marknadsandel’, ’Vinstmarginal’ och ’Långsiktig produktpotential’. Dessa faktorer är i sin tur indelade i subfaktorer som har sina egna uppsättningar av drivare. Efter att ha använt modellen för att utvärdera de tre städerna konstaterades det att Shanghai är den lämpligaste staden för ett marknadsinträde av EV Power, främst på grund av stadens dominans på marknaden för privatanvända elbilar och ett gynnsamt regelverk. Slutligen hittades tre framgångsfaktorer för ett sådant inträde: ’Fokusera på tjänster’, ’Bibehåll partner-relationer’ och ’Inträd tidigt’. / Personal electric vehicles (EV) is an emerging technology that has gained much momentum in several markets during the past decade, and China is currently one of the markets where the growth in EV sales is the highest. Since the industry is still in its infancy, there are currently no clear structures regarding the relationships between different actors that apply to all markets globally, leading to great uncertainty in strategic decisions. The commissioner of this study is Hong Kong EV Power Ltd. (EV Power), a producer of EV supply equipment (EVSE) and related services in Hong Kong, which aspires to enter the Chinese mainland in the near future. However, EV Power has yet to decide which city they want to target first. This thesis aims to formulate a model that can be used to evaluate and compare geographic markets for a market entry by an EVSE company. Furthermore, the model is tested on three cities in Mainland China (Beijing, Shanghai and Shenzhen), in order to derive the most attractive city for EV Power and to evaluate the adequacy of the model. Lastly, with the results from the city evaluation, as a point of departure, success factors for an entry into Mainland China by the commissioning company will be summarized. In order to achieve this objective, four distinct data collection methods have been used: First, theory was studied, in order to gain background knowledge as well as to understand specific factors that impact a market entry decision such as this. Second, EV Power’s current business in Hong Kong was observed, with a view to achieve an understanding of what has led the company to experience success in its home market. Third, Interviews with industry experts were conducted, so as to get a perspective on the industry as a whole. Fourth and last, secondary data for the different cities was collected, for the sake of evaluating them according to the developed model. The final model consists of five main factors that encompass the elements that influence a cities level of attractiveness for entry by an EV charging station supplier. The identified factors are: ‘Market accessibility’, ‘Short-term demand’, ‘Expected market share’, ‘Profit margin’, and ‘Long-term product potential’. These factors are in turn divided into sub factors that have their own set of drivers. Using the model to evaluate the cities, it was found that Shanghai is the most suitable city for a market entry by EV Power, mainly due to its dominance in the market for private EVs and a favourable regulatory environment. Finally, three main success factors, for such a market entry, were found: ‘Focus on services’, ‘Maintain partner relationships’, and ‘Enter early’.
362

Harnessing demand flexibility to minimize cost, facilitate renewable integration, and provide ancillary services

Kefayati, Mahdi 18 September 2014 (has links)
Renewable energy is key to a sustainable future. However, the intermittency of most renewable sources and lack of sufficient storage in the current power grid means that reliable integration of significantly more renewables will be a challenging task. Moreover, increased integration of renewables not only increases uncertainty, but also reduces the fraction of traditional controllable generation capacity that is available to cope with supply-demand imbalances and uncertainties. Less traditional generation also means less rotating mass that provides very short term, yet very important, kinetic energy storage to the system and enables mitigation of the frequency drop subsequent to major contingencies but before controllable generation can increase production. Demand, on the other side, has been largely regarded as non-controllable and inelastic in the current setting. However, there is strong evidence that a considerable portion of the current and future demand, such as electric vehicle load, is flexible. That is, the instantaneous power delivered to it needs not to be bound to a specific trajectory. In this thesis, we focus on harnessing demand flexibility as a key to enabling more renewable integration and cost reduction. We start with a data driven analysis of the potential of flexible demands, particularly plug-in electric vehicle (PEV) load. We first show that, if left unmanaged, these loads can jeopardize grid reliability by exacerbating the peaks in the load profile and increasing the negative correlation of demand with wind energy production. Then, we propose a simple local policy with very limited information and minimal coordination that besides avoiding undesired effects, has the positive side-effect of substantially increasing the correlation of flexible demand with wind energy production. Such local policies could be readily implemented as modifications to existing "grid friendly" charging modes of plug-in electric vehicles. We then propose improved localized charging policies that counter balance intermittency by autonomously responding to frequency deviations from the nominal frequency and show that PEV load can offer a substantial amount of such ancillary services. Next, we consider the case where real-time prices are employed to provide incentives for demand response. We consider a flexible load under such a pricing scheme and obtain the optimal policy for responding to stochastic price signals to minimize the expected cost of energy. We show that this optimal policy follows a multi-threshold form and propose a recursive method to obtain these thresholds. We then extend our results to obtain optimal policies for simultaneous energy consumption and ancillary service provision by flexible loads as well as optimal policies for operation of storage assets under similar real-time stochastic prices. We prove that the optimal policy in all these cases admits a computationally efficient form. Moreover, we show that while optimal response to prices reduces energy costs, it will result in increased volatility in the aggregate demand which is undesirable. We then discuss how aggregation of flexible loads can take us a step further by transforming the loads to controllable assets that help maintain grid reliability by counterbalancing the intermittency due to renewables. We explore the value of load flexibility in the context of a restructured electricity market. To this end, we introduce a model that economically incentivizes the load to reveal its flexibility and provides cost-comfort trade-offs to the consumers. We establish the performance of our proposed model through evaluation of the price reductions that can be provided to the users compared to uncontrolled and uncoordinated consumption. We show that a key advantage of aggregation and coordination is provision of "regulation" to the system by load, which can account for a considerable price reduction. The proposed scheme is also capable of preventing distribution network overloads. Finally, we extend our flexible load coordination problem to a multi-settlement market setup and propose a stochastic programming approach in obtaining day-ahead market energy purchases and ancillary service sales. Our work demonstrates the potential of flexible loads in harnessing renewables by affecting the load patterns and providing mechanisms to mitigate the inherent intermittency of renewables in an economically efficient manner. / text
363

Integrated Compact Drives for Electric and Hybrid Electric Vehicles

Jin, Lebing January 2016 (has links)
To develop more competitive solutions, one of the trends in the development of drive systems for electric and hybrid electric vehicles (EVs/HEVs) is to integrate the power electronic converter and the electric motor. This thesis aims to investigate the performance and the operation of modular converters in integrated motor drive systems for EVs/HEVs. In the first part, the concept of integrated modular motor drive systems for EVs/HEVs is introduced. Three suitable modular converter topologies, namely, the stacked polyphase bridges (SPB) converter, the parallel-connected polyphase bridges (PPB) converter and the modular high frequency (MHF) converter, are evaluated and compared with conventional electric drives in terms of power losses, energy storage requirements, and semiconductor costs. In the second part of the thesis, the harmonic content of the dc-link current of the SPB converter is analyzed. By adopting an interleaving modulation the size of the dc-link capacitor can be reduced without increasing the switching frequency, which is beneficial for achieving a compact integrated system. This method allows for around 80% reduction of the dc-link capacitance for vehicle drives, resulting in a significant size reduction of the power converter and improved integration. Finally, a communication-based distributed control system for the SPB converter is presented. The communication delay arising from the serial communication is inevitable, thus a timing analysis is also presented. It has been found that stability is maintained even when the baud rate of the SPI communication is lower than 1 Mbps, indicating that other communication protocols with lower bandwidths can also be adopted for this topology. The analytical investigations provided in this thesis are validated by experiments on a four-submodule laboratory prototype. Experimental results verify the correctness of the theoretical analysis, as well as the dynamic performance of the distributed control system. / <p>QC 20161121</p>
364

Electric cars in China : energy, infrastructure and market potentials

Liu, Jian January 2012 (has links)
The electric vehicle (EV) has been regarded as one of the most promising alternative fuel vehicle technologies that could reduce China’s energy reliance on imported oil and transport sector carbon emissions. The success of EVs in China will depend on a series of determinants including their energy consumption and emission reduction potentials, battery performance and costs, charging infrastructure provision, the driving behaviour and the commercialization strategies. Some issues have been intensively investigated by previous research whilst some others gradually receive academic and governmental attentions. Instead of covering all determinants, this thesis focuses on four key aspects of the electric car development in China: the energy consumption and carbon emissions of electric cars based on the country’s energy mix; the expected electric car driving behaviour and its impacts on the power grid; the deployment strategy of charging infrastructure and the business operation models that could reduce the purchase cost of electric cars and accelerate their market diffusion. The research finds that according to the current energy mix and driving behaviour in China, the introduction of electric cars would largely reduce the transport sectors’ oil consumption. However, the carbon emission saving of electric cars requires a synchronized progress in the energy industry and the power grid infrastructure. Without the growing adoption of renewable sources in the electricity generation mix and the high efficient power transmission infrastructure, electric cars could achieve little environmental benefits particularly for carbon emission reduction. This research also finds that the current external costs of carbon emissions from cars are not high enough to justify financial policies that would favour electric vehicles. Moving towards cleaner technologies at present may not be justified on economic terms but it is justified on political and environmental terms. In addition, the performance of current electric cars, the driving range per charge in particular, is still significantly inferior to conventional vehicles running on petroleum fuels, which poses a remarkable challenge for electric cars’ market acceptance and implies the importance of charging infrastructure provision. This research estimates the charging impact of electric cars on the power grid in two case study cities through comparing charging infrastructure deployment strategies integrating three charging methods in both cities. Some innovative business operating models that aim to reduce the high initial purchase costs of electric cars are simulated. It shows all these models require substantial political and financial interventions to stimulate both supply (charging service and infrastructure provision) and demand (consumers purchase) in the early stage of market penetration for electric cars. Finally, the thesis provides recommendations for the policy implementation timing and stresses the importance of the parallel development in the upstream low carbon energy supply and the downstream vehicle (battery) research and development (R&D) in the near term.
365

The energy consumption mechanisms of a power-split hybrid electric vehicle in real-world driving

Lintern, Matthew A. January 2015 (has links)
With increasing costs of fossil fuels and intensified environmental awareness, low carbon vehicles, including hybrid electric vehicles (HEVs), are becoming more popular for car buyers due to their lower running costs. HEVs are sensitive to the driving conditions under which they are used however, and real-world driving can be very different to the legislative test cycles. On the road there are higher speeds, faster accelerations and more changes in speed, plus additional factors that are not taken into account in laboratory tests, all leading to poorer fuel economy. Future trends in the automotive industry are predicted to include a large focus on increased hybridisation of passenger cars in the coming years, so this is an important current research area. The aims of this project were to determine the energy consumption of a HEV in real-world driving, and investigate the differences in this compared to other standard drive cycles, and also compared to testing in laboratory conditions. A second generation Toyota Prius equipped with a GPS (Global Positioning System) data logging system collected driving data while in use by Loughborough University Security over a period of 9 months. The journey data was used for the development of a drive cycle, the Loughborough University Urban Drive Cycle 2 (LUUDC2), representing urban driving around the university campus and local town roads. It will also have a likeness to other similar driving routines. Vehicle testing was carried out on a chassis dynamometer on the real-world LUUDC2 and other existing drive cycles for comparison, including ECE-15, UDDS (Urban Dynamometer Driving Schedule) and Artemis Urban. Comparisons were made between real-world driving test results and chassis dynamometer real-world cycle test results. Comparison was also made with a pure electric vehicle (EV) that was tested in a similar way. To verify the test results and investigate the energy consumption inside the system, a Prius model in Autonomie vehicle simulation software was used. There were two main areas of results outcomes; the first of which was higher fuel consumption on the LUUDC2 compared to other cycles due to cycle effects, with the former having greater accelerations and a more transient speed profile. In a drive cycle acceleration effect study, for the cycle with 80% higher average acceleration than the other the difference in fuel consumption was about 32%, of which around half of this was discovered to be as a result of an increased average acceleration and deceleration rate. Compared to the standard ECE-15 urban drive cycle, fuel consumption was 20% higher on the LUUDC2. The second main area of outcomes is the factors that give greater energy consumption in real-world driving compared to in a laboratory and in simulations being determined and quantified. There was found to be a significant difference in fuel consumption for the HEV of over a third between on-road real-world driving and chassis dynamometer testing on the developed real-world cycle. Contributors to the difference were identified and explored further to quantify their impact. Firstly, validation of the drive cycle accuracy by statistical comparison to the original dataset using acceleration magnitude distributions highlighted that the cycle could be better matched. Chassis dynamometer testing of a new refined cycle showed that this had a significant impact, contributing approximately 16% of the difference to the real-world driving, bringing this gap down to 21%. This showed how important accurate cycle production from the data set is to give a representative and meaningful output. Road gradient was investigated as a possible contributor to the difference. The Prius was driven on repeated circuits of the campus to produce a simplified real-world driving cycle that could be directly linked with the corresponding gradients, which were obtained by surveying the land. This cycle was run on the chassis dynamometer and Autonomie was also used to simulate driving this cycle with and without its gradients. This study showed that gradient had a negligible contribution to fuel consumption of the HEV in the case of a circular route where returning to the start point. A main factor in the difference to real-world driving was found to be the use of climate control auxiliaries with associated ambient temperature. Investigation found this element is estimated to contribute over 15% to the difference in real-world fuel consumption, by running the heater in low temperatures and the air conditioning in high temperatures. This leaves a 6% remainder made up of a collection of other small real-world factors. Equivalent tests carried out in simulations to those carried out on the chassis dynamometer gave 20% lower fuel consumption. This is accounted for by degradation of the test vehicle at approximately 7%, and the other part by inaccuracy of the simulation model. Laboratory testing of the high voltage battery pack found it constituted around 2% of the vehicle degradation factor, plus an additional 5% due to imbalance of the battery cell voltages, on top of the 7% stated above. From this investigation it can be concluded that the driving cycle and environment have a substantial impact of the energy use of a HEV. Therefore they could be better designed by incorporating real-world driving into the development process, for example by basing control strategies on real-world drive cycles. Vehicles would also benefit from being developed for use in a particular application to improve their fuel consumption. Alternatively, factors for each of the contributing elements of real-world driving could be included in published fuel economy figures to give prospective users more representative values.
366

Contribution to the Control of the Hybrid Excitation Synchronous Machine for Embedded Applications / Contribution à la commande d’une machine synchrone à double excitation pour des applications embarquées

Mbayed, Rita 12 December 2012 (has links)
Le travail présenté dans cette thèse est une contribution à la commande de la Machine Synchrone à Double Excitation (MSDE) pour des applications embarquées. La MSDE allie les avantages de la machine synchrone à aimants permanents et la machine synchrone à rotor bobiné. Le flux d'excitation dans cette machine est généré par deux sources : les aimants permanents et un enroulement qui est placé au stator afin d'éviter les contacts glissants. Cette dernière source permet de régler le flux dans l'entrefer. Le modèle de la machine est basé sur un modèle de Park et prend en considération les pertes fer et la saturation des circuits magnétiques. Les paramètres du prototype existant au laboratoire ont été identifiés. La commande de la MSDE est effectuée en deux modes : générateur et moteur. En génératrice, l'application visée est la génération électrique en avionique. Deux réseaux de distribution sont traités : Réseau à haute tension et à fréquence variable et réseau haute tension DC. Dans ce dernier cas, la MSDE est associée à un pont redresseur à diodes. Dans les deux cas, la commande est élaborée dans le but de maintenir l'amplitude de la tension constante via le control du courant d'excitation uniquement. Le control est scalaire. L'approche est validée par simulation avec Matlab/Simulink et par expérimentation. Pour le mode moteur, l'application visée est la propulsion dans un véhicule électrique. Une commande optimale des courants est étudiée en vue de minimiser les pertes. Les pertes joules sont considérées premièrement. Ensuite, les pertes fer sont ajoutées. Finalement, le problème de minimisation est étendu pour inclure les pertes dues à l'onduleur et au hacheur. L'optimisation par la méthode des multiplicateurs de Lagrange (Kuhn-Tucker conditions) est utilisée pour trouver des expressions analytiques des courants statoriques et inducteur optimaux. Des simulations avec Matlab/Simulink prouvent que la solution obtenue est celle qui assure les pertes minimales tout au long du nouveau cycle de conduite européen. / This thesis is a contribution to the control of the Hybrid Excitation Synchronous Machine (HESM) in embedded applications. The HESM combines the advantages of the Permanent Magnets (PM) machine and the wound rotor machine. The excitation flux in this machine is produced by two different sources: the PMs and a DC field winding that is placed at the stator to preserve a brushless structure. The latter source is used to control the flux in the air gap. The machine model is based on a Park model and takes into account the iron losses and the magnetic circuit saturation effect. The electric parameters of the laboratory prototype are identified. The machine is controlled in generator mode and motor mode. In power generation system, the study treats in particular the aircraft power supply in more electric aircrafts. Two distribution networks are studied: High voltage variable frequency network and high voltage DC network. In the latter case, the HESM is coupled to a diode bridge rectifier. In both cases, the control aims to maintain the output voltage magnitude equal to its reference via action on the field current only. The control is scalar. Simulation with Matlab/Simulink and experiments validate the approach. For the motor mode, the attention is paid to the electric propulsion in an electric vehicle. An optimal current control with minimal losses is elaborated. The copper losses are considered in a first place. Iron losses are added next. Finally, the optimization problem is extended and it includes the losses due to the inverter and the chopper. Analytical expressions of the reference armature and field currents are computed using extended Lagrange multiplier method (Kuhn-Tucker conditions). Simulation with Matlab/Simulink software proves that the analytical solution yields indeed to the current combination that guarantees the minimal losses over the New European Driving Cycle.
367

Contributions à la commande et à la conception des machines à réluctance variable à double saillance / Contributions to the control and design of the switched reluctance machine

Rain, Xavier 23 September 2013 (has links)
Dans le domaine du véhicule électrique, la chaîne de traction allant de la batterie de stockage aux roues en passant par le moteur constitue le cœur du système. Elle bénéficie régulièrement d’innovations technologiques rendant ce véhicule de plus en plus attractif. Actuellement, les motorisations proposées par les constructeurs sont classiques, de type synchrone à rotor bobiné, à aimant permanent ou asynchrone. De conception éprouvée et dotées de lois de commande complexes et parfaitement maîtrisées, elles offrent de bonnes performances.Cependant, les industriels explorent de nouvelles motorisations moins conventionnelles permettant de réduire leur coût de fabrication, tout en maintenant les performances. Une des solutions possibles est la machine à réluctance variable à double saillance (MRVDS). En effet, elle est de conception simple et constituée de matériaux peu couteux. Son rotor complètement passif lui confère une très bonne robustesse et une vitesse de rotation élevée, nécessaire à une certaine compacité.Néanmoins, son pilotage est beaucoup plus complexe que pour les autres machines, elle est relativement bruyante et son couple présente des ondulations non négligeables.Nos travaux ont pour but de contribuer à l’amélioration des performances de la MRVDS du point de vue contrôle, caractéristiques de couple et efficacité énergétique sur une plage de vitesse importante. Ils ont alors été conduits selon deux axes : un axe commande et un axe conception.Afin de satisfaire un contrôle du couple le plus parfait possible, de nouveaux régulateurs de courant à la fois performants et relativement simples à implémenter sur cible logicielle ont été présenté dans un premier temps. Ensuite, nous avons proposé une implémentation partitionnée de la commande de la MRVDS sur cibles logicielle et matérielle. L’objectif est ici de conserver les performances de la commande dans le cas de l’utilisation d’un processeur économique, dont la période d’échantillonnage serait relativement importante, et tout particulièrement à haute vitesse. Une carte FPGA (Fied Programmable Gate Array) a alors été mise en œuvre.Pour améliorer les caractéristiques de couple en fonction de la vitesse ainsi que le rendement de l’ensemble moteur-convertisseur, une nouvelle structure de MRVDS non conventionnelle a été proposée. Elle est munie d’un bobinage auxiliaire créant une excitation magnétique dans chaque phase.Une étude a d’abord été menée à l’aide de simulations basées sur un nouveau modèle. Elle a permis de mettre en évidence les avantages d’une excitation par rapport à une MRVDS classique. Afin de valider les résultats, un prototype a ensuite été conçu, réalisé et expérimenté.Une part importante de ces travaux a ainsi été consacrée à la mise en œuvre de plateformes expérimentales et à la réalisation de nombreux essais permettant de valider les développements théoriques, tant du point de vue commande sur une MRVDS 8/6 que conception sur une MRVDS 6/4. / For electric vehicles, traction from storage battery to the wheels through the engine is the heart of the system. It regularly enjoys technological innovations making this vehicle more attractive. Currently, machines offered by manufacturers are classic, synchronous and induction machines. With complex laws, they offer good performance.However, manufacturers are exploring new unconventional machines to reduce their manufacturing cost while maintaining performance. One possible solution is the switched reluctance machine (SRM). Indeed, its design is simple and made of inexpensive materials. Its rotor completely passive gives it a very good robustness and high rotational speed required for certain compactness. However, its operation is much more complex than for other machines, it is relatively noisy and has significant torque ripple.Our work contributes to the improvement of SRM’s performance in terms of control torque characteristics and global efficiency over a large range speed. They were driven on two axes: one control axis and one design axis.To satisfy a torque control as perfect as possible, new currents controller both efficient and relatively simple to implement on software target were first presented. Then we proposed a SRM's control implementation on hardware and software targets. The objective is to maintain the performances in the case of an important sampling period, especially at high speeds. So an FPGA circuit (Fied Programmable Gate Array) was used.To improve torque characteristics depending on the speed, and global efficiency, a new SRM structure has been proposed. It is provided with an auxiliary coil creating a magnetic excitation in each phase. A study was initially conducted using simulations based on a new model. It helped to highlight the benefits of excitement compared to a conventional SRM. To validate the results, a prototype was then designed, built and tested.An important part of this work has been devoted to the implementation of experimental platforms and implementation of numerous tests to validate the theoretical developments, both in terms of control on a 8/6 SRM and design on a 6/4 SRM.
368

Commande tolérante aux défauts d’une chaine de traction d’un véhicule électrique / Fault tolerant control of electric vehicle power train

Raisemche, Aziz 27 November 2014 (has links)
Les diverses normes internationales obligent les constructeurs automobiles à optimiser les chaînes de propulsion conventionnelles mais surtout à développer d’autres alternatives de motorisation dont l’une des plus prometteuses est le véhicule électrique. Néanmoins ces nouvelles propulsions doivent garantir les mêmes performances et le même niveau de sureté de fonctionnement (fiabilité et sécurité en l’occurrence). La chaîne de propulsion électrique est conçue autour d’un nombre important de constituants (machine électrique, capteur(s), convertisseur(s) de l’électronique de puissance, etc.) qui peuvent être le siège de défauts. La détection et la localisation de ces défauts sont indispensables mais pas suffisantes pour assurer la sureté de fonctionnement du système. En effet pour assurer un fonctionnement en mode dégradé, il faut mettre en œuvre une architecture de commande tolérante aux fautes. L'objectif principal de cette thèse est de proposer des nouvelles architectures de commande tolérante aux défauts (Fault Tolerant Control en anglais) d’un véhicule électrique propulsé par une machine asynchrone, en présence de plusieurs types de défaut du capteur mécanique. Cette thèse est organisée en 4 chapitres.Le Chapitre 1 est un état de l’art exhaustif avec une analyse critique des architectures et des systèmes de contrôle commande tolérants aux fautes des chaînes de traction électrique ainsi qu'un état de l'art des différents défauts qui peuvent apparaitre dans la chaine de traction électrique. Le Chapitre 2 propose deux architectures de commande tolérante aux fautes : l’Hybride FTC et le GIMC (Generalised Internal Model Control) ; l’approche Hybride FTC est une combinaison de deux contrôleurs, le premier est un régulateur PI pour le mode sain et le second un correcteur robuste H infini pour le mode défaillant. L’architecture GIMC permet la restructuration de la loi de commande d'une manière adaptative. Elle est conçue afin d’assurer une bonne robustesse du système en présence de défaut grâce à une boucle interne faisant office de boucle de correction et de diagnostic.Le Chapitre 3 est consacré exclusivement à la commande tolérante aux fautes à base d'algorithme de vote, en faisant une étude comparative de 4 algorithmes avec trois topologies différentes : une première structure est proposée sur la sortie du système, une deuxième structure est appliquée sur la commande du système, et la troisième structure est une hybridation des deux précédentes.Le Chapitre 4 est dédié à la validation expérimentale des architectures décrites précédemment. Les résultats obtenus montrent l’efficacité des approches FTC proposées. / The various international standards require automakers to optimize conventional power train but mainly to develop other alternatives to drive, one of the most promising is the electric vehicle. However, these new drives should guarantee the same performance and the same level of dependability (reliability and security in this case).Electric power train is built around a large number of components (electrical machine, the sensor, the converter, power electronics, etc.) which may be affected by defects. The detection and localization of these defects are essential but not sufficient to ensure the dependability of the system. Indeed, to ensure operation in degraded mode, you must implement architecture of fault tolerant control (FTC). The main objective of this thesis is to propose new fault tolerant control architectures of an electric vehicle induction machine power train in the presence of several types of mechanical sensor failure. This thesis is organized into four chapters.Chapter 1 is a comprehensive state of the art with a critical analysis of architectures and control systems tolerant to faults of electric powertrains and a state of the art of the various defects that may occur in the chain of electric traction.Chapter 2 proposes two architectures of fault tolerant control: Hybrid FTC and GIMC (Generalised Internal Model Control); Hybrid FTC approach is a combination of two controllers, the first is a PI controller for the sound mode and the second a robust controller for the failed H infinity mode. The architecture allows GIMC restructuring the control law in an adaptive manner. It is designed to ensure robustness of the system in the presence of a fault with an inner loop acting loop correction and diagnosis.Chapter 3 is devoted exclusively to the algorithm voting fault tolerant control based on comparative study of four algorithms with three different topologies: a first structure is proposed on the system output, a second structure is applied system control, and the third structure is a two preceding hybridization.Chapter 4 is devoted to the experimental validation of the architecture described above. The results show the effectiveness of the approaches proposed FTC.
369

Analyse statistique de données issues de batteries en usage réel sur des véhicules électriques, pour la compréhension, l’estimation et la gestion des phénomènes de vieillissement / Statistical analysis of battery signals in real electric vehicle uses, for comprehension, estimation and management of ageing phenomena

Barré, Anthony 17 October 2014 (has links)
Le marché des véhicules électriques connait actuellement un développement important motivé par diverses raisons. Cependant, des limites liées à leurs performances constituent des inconvénients majeurs à une croissance des ventes de plus grande importance. Les performances et durée de vie des batteries utilisées sont au cœur des préoccupations des utilisateurs. Les batteries sont sujettes à des pertes de performances au fil du temps, dus à des phénomènes complexes impliquant des interactions entre les diverses conditions de vie de celles-ci. Dans l'objectif d'améliorer la compréhension et l'estimation du vieillissement d'une batterie, ces travaux étudient des données issues d'usages réels de batteries sur des véhicules électriques. En particulier, l'étude consiste en l'adaptation d'approches statistiques fondées sur les données mesurées, mettant en évidence des interactions entre variables, ainsi que la création de méthodes d'estimation du niveau de performance de batterie uniquement basé sur les mesures obtenues. Les résultats de ces méthodologies ont permis d'illustrer l'apport d'une approche statistique, par exemple en démontrant la présence d'informations contenues dans les signaux issus de la batterie, utiles pour l'estimation de son état de santé. / Due to different reason The electrical vehicle market is undergoing important developments. However the limits associated with performance represent major drawbacks to increase the sales even more. The batteries performance and lifetime are the main focus of EV users. Batteries are subject to performance loss due to complex phenomena implying interactions between the different life conditions of the battery. In order to improve the understanding and estimation of battery aging, the studies were based on datasets from real use ev batteries. More precisely, this study consists in the adaptation and application of statistical approaches on the available data in order to highlight the interactions between variables, as well as the creation of methods for the estimation of battery performance. The obtained results allowed to illustrate the interests of a statistical approach. For example the demonstration of informations contained in the signals coming from the battery which are useful for the estimation of its state of health.
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Estudo prospectivo da inserção de veículos elétricos no Paraguai e na Bolívia à luz de uma avaliação econômico-financeira / Prospective study of electric vehicle insertion in Paraguay and Bolivia, by means of an economic and financial assessment

Nybroe, Carlos Eduardo Centurion 27 March 2015 (has links)
Este trabalho apresenta um estudo exploratório do potencial do Paraguai e da Bolívia para o desenvolvimento de uma indústria de mobilidade elétrica, avaliando a viabilidade de substituição da frota convencional de veículos leves, propulsados atualmente por motores à combustão interna (VCI), por veículos elétricos (VE) equivalentes. O estudo leva em consideração critérios econômicos, energéticos, ambientais, geopolíticos e disponibilidade de recursos naturais. Por tanto, são consideradas duas situações de substituição. No primeiro, por veículos elétricos disponíveis no mercado internacional (VE) e, alternativamente, por veículos elétricos com baterias de Li-ion, resultado da implantação e desenvolvimento de uma indústria de VE`s e outra de baterias de íons de lítio (Li-ion). Aproveitando assim, as vantagens estratégicas de recursos naturais proveniente do Salar de Uyuni Bolívia e da disponibilidade de energia elétrica no Paraguai, considerando a utilização de parte da potência da usina de Itaipu, propriedade do Paraguai e atualmente cedida a seu sócio no empreendimento, o Brasil, bem como a partir das abundantes reservas de gás natural boliviano e o potencial de ambos os países para o desenvolvimento de projetos de fontes renováveis. A indústria de baterias para os automóveis elétricos pode ser localizada na Bolívia, perto dos recursos e com grandes avanços tecnológicos e investimentos do governo na área nos últimos anos, enquanto a de VEL pode ser sediada no Paraguai que na atualidade possui um grande interesse de investidores estrangeiros. Os governos poderiam fomentar o projeto com iniciativas, como subsídios no custo da energia utilizada para o abastecimento de VE`s, ou no custo de investimento inicial do veículo. Poderia também fornecer financiamento para a aquisição de VE`s a taxas menores as do mercado. As estimativas conduzidas neste trabalho mostram que uma eventual substituição da frota de veículos leves VCI por VE no período de 10 anos, geraria benefícios econômicos cumulativos para o Paraguai de US$ 1.031 milhões e para Bolívia de US$ 1.373 milhões. Essa substituição permitiria uma redução das emissões de Gases de Efeito estufa (GEE) de 8.398 GgCO2 para o Paraguai e 9.420 7 GgCO2 para a Bolívia. Inicialmente seriam produzidos 40 mil veículos por ano em cada país para atingir a escala necessária para a redução dos custos das BIL`s. A ideia subjacente é ganhar escala local para a cadeia de produção inicial e, em seguida, acessar os mercados de América latina e o mundo. / This document presents an exploratory study of the potential of Paraguay and Bolivia for the development of an electric mobility industry, assessing the viability of replacing conventional light vehicle fleet, currently driven by internal combustion engines (ICE), for electric vehicles (EV) equivalent. The study takes into account economic, energy, environmental, geopolitical, and availability of natural resources criteria. Therefore, two replacement situations are considered. In the first, for EV`s currently available in the international market and, alternatively, for electric vehicles with Li-ion batteries, due to the implementation and development of both, an electric vehicle and a lithium-ion batteries industry. Leveraging so, the strategic advantages of natural resources from the Salar de Uyuni - Bolivia and the availability of electricity. This considering the use of part of the over-potential of the Itaipu power plant, owned by Paraguay and currently assigned to his associated in the undertaken, Brazil, and from Bolivian natural gas abundant reserves and the potential of both countries for the development of renewable projects. The battery industry for electric cars could be located in Bolivia, because of the proximity of the lithium resources and the technological breakthroughs and investments in the area of the Bolivian government in recent years, while the LEV industry could be based in Paraguay, which currently has a great appeal for foreign investors. Governments could promote the project with incentives such as subsidies in the cost of energy used to supply EV`s, or the cost of the initial investment vehicle, it also could provide funding for the acquisition of EV`s at lower rates. Estimates conducted in this study in a ten year basis show that any replacement of the ICE light vehicle fleet for EV would generate cumulative economic benefits to Paraguay for US$ 1,031 million, and for Bolivia US$ 1,373 million. This substitution would reduce Greenhouse Gases emissions (GHG) in 8,398 GgCO2 for Paraguay and 9,420 GgCO2 for Bolivia. Initially, 40,000 vehicles per year in each country would be produced to achieve the scale required for reducing BIL`s costs. The underlying idea is to make local scale for initial production chain and then access the Latin America markets and the world.

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