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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.
21

Development of simulation tools, control strategies, and a hybrid vehicle prototype

Pei, Dekun 14 November 2012 (has links)
This thesis (1) reports the development of simulation tools and control strategies for optimizing hybrid electric vehicle (HEV) energy management, and (2) reports the design and testing of a hydraulic hybrid school bus (HHB) prototype. A hybrid vehicle is one that combines two or more energy sources for use in vehicle propulsion. Hybrid electric vehicles have become popular in the consumer market due to their greatly improved fuel economy over conventional vehicles. The control strategy of an HEV has a paramount effect on its fuel economy performance. In this thesis, backward-looking and forward-looking simulations of three HEV architectures (parallel, power-split and 2-mode power-split) are developed. The Equivalent Cost Minimization Strategy (ECMS), which weights electrical power as an equivalent fuel usage, is then studied in great detail and improvements are suggested. Specifically, the robustness of an ECMS controller is improved by linking the equivalence factor to dynamic programming and then further tailoring its functional form. High-fidelity vehicle simulations over multiple drive-cycles are performed to measure the improved performance of the new ECMS controller, and to show its potential for online application. While HEVs are prominent in the consumer market and studied extensively in current literature, hydraulic hybrid vehicles (HHVs) only exist as heavy utility vehicle prototypes. The second half of this thesis reports design, construction, and testing of a hydraulic hybrid school bus prototype. Design considerations, simulation results, and preliminary testing results are reported, which indicate the strong potential for hydraulic hybrids to improve fuel economy in the school bus vehicle segment.
22

Electric cars : The climate impact of electric cars, focusing on carbon dioxide equivalent emissions

Ly, Sandra, Sundin, Helena, Thell, Linda January 2012 (has links)
This bachelor thesis examines and models the emissions of carbon dioxide equivalents of the composition of automobiles in Sweden 2012. The report will be based on three scenarios of electricity valuation principles, which are a snapshot perspective, a retrospective perspective and a future perspective. The snapshot perspective includes high and low values for electricity on the margin, the retrospective perspective includes Nordic and European electricity mix and the future perspective includes electricity on the margin for modest and high climate goals at 2030. The study is applied to an upcoming climate smart district, Brunnshög in Lund, and the goal is to determine the amount of emissions of carbon dioxide equivalents for the mentioned alternatives. The environmental effects depends largely on the fuel consumption for the compared types of cars and what electricity valuation principle that is used. The car fleet of 2012 generated 10 300 tonnes of carbon dioxide emissions. The future car fleet generated 400 tonnes of emissions for Nordic electricity mix, 3 200 tonnes for European electricity mix, 3 100 tonnes for electricity on the margin with low values, 5 800 tonnes for electricity on the margin with high values, 1 200 tonnes for electricity on the margin at 2030 for high climate goals and 4 600 tonnes for electricity on the margin at 2030 for modest climate goals. The emissions of carbon dioxide equivalents are at least halved in Brunnshög if 100 % electric cars are used instead of the composition of petrol, diesel and ethanol cars that are primarily used in Sweden 2012. Hence, the result shows that the electric car is very beneficial from an environmental and health perspective, compared to the composition of cars in Sweden 2012. However, how beneficial the electric car is, largely depends on the fuel consumption for both the electric car and the alternative compared with. Although to be able to increase the use of electric cars there are many challenges that need to be dealt with. In order to increase the use of electric cars, it will require further work in the development of batteries, expansion of charging points and other incentives, such as legislation and investments. It will also require a significant technology development to increase the range of the electric car. A natural step in the transition phase could be plug-in hybrids. It is also important to continue to implement climate smart districts, such as Brunnshög in Lund.
23

Analysis of the fuel economy potential of a direct injection spark ignition engine and a CVT in an HEV and a conventional vehicle based on in-situ measurements

Min, Byung-Soon 28 August 2008 (has links)
Not available / text
24

Μελέτη και κατασκευή εργαστηριακής διάταξης φόρτισης του ηλεκτρικού κινητήρα ενός ηλεκτροκίνητου οχήματος

Συρίγος, Στυλιανός 01 February 2013 (has links)
Η παρούσα διπλωματική εργασία πραγματεύεται το σχεδιασμό και την κατασκευή διάταξης φόρτισης του κινητήρα ενός ηλεκτροκίνητου οχήματος. Η εργασία αυτή εκπονήθηκε στο Εργαστήριο Ηλεκτρομηχανικής Μετατροπής Ενέργειας του Τμήματος Ηλεκτρολόγων Μηχανικών και Τεχνολογίας Υπολογιστών της Πολυτεχνικής Σχολής του Πανεπιστημίου Πατρών. Κύριος σκοπός της διπλωματικής εργασίας είναι η κατασκευή ενός αμφίδρομου ηλεκτρονικού μετατροπέα ισχύος, που θα ελέγχει μια μηχανή συνεχούς ρεύματος ξένης διέγερσης, η οποία συνδέεται μέσω ενός συστήματος μετάδοσης με τον κινητήρα ενός ηλεκτροκίνητου οχήματος. Απώτερος στόχος είναι η εξομοίωση όλων των πιθανών φορτίων που ασκούνται σε έναν κινητήρα κατά την κίνηση του οχήματος. Αρχικά αναλύεται το φορτίου του κινητήρα κατά την κίνηση του οχήματος και αναζητούνται τρόποι για την εξομοίωση και τη σύνδεση των εξωτερικών δυνάμεων που ασκούνται στο όχημα με τη ροπή της μηχανής. Στη συνέχεια αναλύθηκε ο αμφίδρομος ηλεκτρονικός μετατροπέας που χρησιμοποιήθηκε για τον έλεγχο της μηχανής συνεχούς ρεύματος και αναζητήθηκαν οι κατάλληλες μέθοδοι για τον έλεγχο του συγκεκριμένου μετατροπέα. Το επόμενο βήμα ήταν η προσομοίωση του συνολικού συστήματος φόρτισης προκειμένου να εξακρθωθεί η ορθή λειτουργία του πριν την κατασκευή, με χρήση του λογισμικού MATLAB/SIMULINK. Τέλος, μελετάται και κατασκευάζεται στο εργαστήριο η πειραματική διάταξη, με τη χρήση της οποίας διεξάγονται οι μετρήσεις για την επιβεβαίωση και την αξιολόγηση της θεωρητικής μελέτης. / This thesis discusses the design and manufacture of a charging device intended for an electric vehicle motor. The work was conducted in the Laboratory of Electromechanical Energy Conversion, Department of Electrical and Computer Engineering, School of Engineering, University of Patras. The main purpose of this thesis is to manufacture a bidirectional electronic power converter able to control a DC motor which is connected with the engine of an electric vehicle via a transmission system. The ultimate goal is to simulate all possible loads exerted on a motor during the vehicle movement. Initially we analyze the load on the engine during vehicle movement and seek ways to simulate and combine the external forces acting on the vehicle with the engine torque. In the sequel the bidirectional electronic power converter used to control the DC motor is analyzed and appropriate control methods are investigated. The next step is to simulate and validate the overall system functionality using MATLAB / SIMULINK, before actually proceeding with the manufacture. Finally, an experimental setup is prepared in our lab, the results of which are utilized to confirm and evaluate the aforementioned theoretical study.
25

2030 Agenda – Implementation of climate-related Sustainable Development Goals in Norway and Germany by using the example of sustainable transportation / Agenda 2030 – Implementering av de klimatrelaterade Globala målen i Norge och Tyskland,exemplifierat genom hållbara transporter

Dietrich, Ina January 2022 (has links)
Since the United Nations adopted the 2030 Agenda and introduced its 17 Sustainable Development Goals in 2015, governments all over the world are working on implementing the framework into national, regional and local levels of administration to reach its targets. Climate-related challenges, including the reduction of CO2 emissions, are often met by using climate mitigation tools such as electric vehicles in sustainable transport matters. Due to this international endeavor, comparisons between partaking member states demonstrate achievements and failures of regulations and contribute to a better understanding and learning from other’s experience. In this thesis, the situation in Norway and Germany is analyzed by addressing the differences and similarities in both countries in establishing battery-driven cars on the markets. The political and socio-economic factors, including the associated variables political structure and policies, the energy and car market, the efforts in developing a sufficient infrastructure with charging stations, the consumers’ behavior and the share of renewable energy sources in the overall electricity production, are described. The framework of policy transfer as well as the comparative analysis assist to conceive the link between political structures and policies in both countries and the outcomes of their political decision-making processes. The analysis shows immense disparities in the implementation of electric vehicles due to the countries’ histories and developments of climate-related policies. Furthermore, the transition of transport not only depends on political stakeholders and advocacy groups but also on the willingness of the citizenry to adopt the new technology.
26

The Potential of Electrification in reducing Emissions from Passenger Cars in Stockholm County by 2030 : A Modeling Study of the Potential of Plug-In Hybrids and All-Electric Cars in reducing Greenhouse Gas Emissions and Air Pollution / Potentialen av elektrifiering att minska utsläppen från personbilar i Stockholms län till 2030 : En modelleringsstudie av potentialen av laddhybrider och elbilar att minska utsläppen av växthusgaser och luftföroreningar

Hedbäck, Arvid January 2021 (has links)
This study examines the potential of electrification in reducing greenhouse gas emissions and air pollution from passenger cars in a short- to mid-term time perspective. Using Stockholm County as a case study, this has been done in a three-step process by modeling the relative change in emissions between 2019 and 2030. Firstly, four scenarios have been created for 2030, each of which state the number of gasoline cars, diesel cars, PHEVs and EVs in use on a municipality-level. Secondly, for each scenario, the movement of traffic has been modeled on a car-by-car basis using the Scaper/MATSim transportation model at KTH. Thirdly, using emission factors from HBEFA, an emission model for 17 pollutants has been created for the modeling of hot emissions, cold start emissions, evaporation losses and non-exhaust emissions. Compared to 2019 emission levels, with EVs and PHEVs accounting for 64.5 % of the car fleet, the optimistic scenarios suggest that emissions of CO2, NMHC and NOx could decrease by up to 43.6, 63.5 and 84.7 %, respectively, by 2030. Besides electrification, for NMHC and NOx, these emission reductions are largely a result of technological improvements of combustion vehicles. Conversely, emissions of particulate matter (PM10 and PM2.5) are projected to increase by up to 45.6 % in the optimistic scenarios. Roughly corresponding to the increase in the total driving distance, this increase can be attributed to the lower cost of driving of electric cars and the projected population increase of 15.5 %.
27

The perception of Chinese electric cars : A quantitative study of Norwegian car owners behavioral intentions of purchasing Chinese electric cars

Mattsson, Viktor, Stephanson, Erik January 2022 (has links)
In a time where environmental issues have become an important topic on the political agenda, car companies have begun transitioning from fossil-fueled vehicles to battery-driven electric vehicles. In this transition, multiple Chinese electric car manufacturers have emerged on the European car market. The purpose with this study has been to investigate Norwegian consumers' perception of Chinese electric car manufacturers. Empirical data was gathered through a self-completion questionnaire that was sent out to Norwegian electric car-related forums and Facebook groups. The results showed that Norwegians had a positive attitude towards electric cars and large intentions of purchasing one. This did not correlate with their attitude and intention of purchasing a Chinese electric car. A contributor to the Norwegians’ negative effect on Chinese electric cars consisted of the individuals’ political views of China. Lastly, it was seen that social norms and perceived behavioral control cannot be considered predictors of the intention. / I en tid där miljöfrågor har blivit ett viktigt ämne på den politiska agendan har bilföretagen påbörjat en övergång från fossildrivna fordon till batteridrivna elfordon. I denna övergång har flera kinesiska elbilstillverkare dykt upp på den europeiska bilmarknaden. Syftet med denna studie har varit att undersöka norska konsumenters uppfattning om kinesiska elbilstillverkare. Empirisk data samlades in genom ett självfyllande frågeformulär som skickades ut till norska elbilsrelaterade forum och Facebook-grupper. Resultaten visade att norrmän hade en positiv inställning mot elbilar och hade stora avsikter att köpa en. Det här korrelerade inte med deras inställning och avsikt om att köpa en kinesisk elbil. En stor bidragande faktor till norrmännens negativa effekt på kinesiska elbilar var individernas politiska syn på Kina. Slutligen uppmärksammades det att sociala normer och upplevd beteendekontroll inte kan betraktas som prediktorer för deras avsikt.
28

Estimating the Potential Life Cycle Environmental Impacts of Current and Future Electric Passenger Cars / Uppskatning av den Potentiella livscykeln Miljöpåverkan av Nuvarande och Framtida Elbilar

Koroma, Michael Samsu January 2018 (has links)
The road transport sector is heavily dependent on fossil-fuel based technologies, and as a result, contribute a significant share towards climate change and other environmental problems. If the transport sector is to reduce its adverse impacts on climate change, then it requires a global shift towards low-carbon technologies. However, deploying these new technologies brings uncertainties regarding their environmental profile, hence, the need for applying a life cycle approach in evaluating their potential environmental impacts. This thesis aim to evaluate the potential life-cycle environmental impacts associated with travelling 1 km in a battery electric cars (BEV) and plug-in hybrid electric cars (PHEV) operated in the EU at present-day, and in the future up till 2050. The study applied the life cycle assessment (LCA) and ReCiPe Midpoint (H) methodologies to assess and calculate the potential life cycle environmental impacts of all vehicle scenarios. The datasets of the vehicles have been modelled with a modular approach by linking together various vehicle components. The future time perspective based on two future scenarios; the Mod-RES, representing the reference future scenario and the High-RES representing a future ambitious policy scenario.   The EU28 electricity production based on Fichtner, et al. was used to model the use phase all vehicle scenarios. The result showed BEV performed best in indicators for global warming (GWP), ozone depletion and fossil resource scarcity. The thesis best estimate for GWP is 5.61E-2 kgCO2 eq resulting from the BEV_High-RES scenario; representing a decrease in GWP of around 80% and 69% when compared to the ICEV and the baseline BEV respectively. On the other hand, the baseline BEV performed worst in impact categories related to human toxicity and damage to ecosystems; the conventional gasoline car showed the lowest estimate for indicators on human toxicity, acidification and eutrophication as defined in the baseline scenario. Nonetheless, the future scenarios showed promising results for all technologies; as projections for stringent environmental regulations, ‘cleaner’ energy systems and continuous advancement in vehicle technologies offered a significant reduction in all impact categories. Notably, the BEV reduced its impact on toxicity categories to around 38% of the initial values for the baseline scanario. Results are strongly dependent on assumptions regarding the vehicle and battery lifetime, the use phase electricity source and the vehicle consumption.  The findings establish the significance of carrying out a full LCA, including future time perspective and assessing impact categories beyond climate change. Also, it underlined the suggestion that production of electric cars raised more concern for EVs than conventional cars; thus, the tendency for environmental problem-shifting and the need for policy-makers to recognise existing trade-offs. / Vägtransportsektorn är starkt beroende av fossilbränslebaserad teknik och bidrar därmed till en betydande andel av klimatförändringen och andra miljöproblem. Om transportsektorn ska minska dess negativa inverkan på klimatförändringen, krävs det en global övergång till teknik med låga koldioxidutsläpp. Utnyttjandet av denna nya teknik medför dock osäkerhet om sin miljöprofil och därmed behovet av att tillämpa ett livscykelperspektiv vid utvärderingen av deras potentiella miljöpåverkan. Avhandlingen presenterar en livscykelanalys av nuvarande och framtida elfordon. Fokus ligger på batteri elbilar (BEV) och plug-in hybrid elbilar (PHEV) som drivs i EU. EU28-elproduktionen baserad på Fichtner, et al. användes för att beräkna de potentiella livscykelmiljöeffekterna av alla fordonsscenarier baserade på effektkategorier definierade i ReCiPe Midpoint (H) -metoden. Resultatet visade att BEV fungerade bäst i indikatorer för global uppvärmning (GWP), ozonförlust och fossila resurserbrist. Avhandlingens bästa uppskattning för GWP är 5,61E-2 kgCO2 ekv som härrör från BEV_High-RES-scenariot; vilket motsvarar en minskning av GWP på cirka 80% och 69% jämfört med ICEV respektive baseline BEV. Å andra sidan har baslinjens BEV den högsta andelen miljöindikatorer relaterade till human toxicitet och skador på ekosystemen. Den konventionella bensinbilen visade den lägsta uppskattningen av indikatorer för human toxicitet, försurning och eutrofiering enligt definitionen i baslinjen. De framtida scenarierna visade emellertid lovande resultat för all teknik, detta förutsätter strängre miljöregler, "renare" energisystem och kontinuerlig framsteg inom fordonsteknik som kommer att erbjuda en betydande minskning av alla påverkningskategorier. I synnerhet reducerade BEV: s påverkan på toxicitetskategorier till omkring 38% av de ursprungliga värdena för baslinjens scanario. Resultaten är starkt beroende av antaganden om fordonets och batteritiden, användningsfasens elkälla och fordonsförbrukningen. Resultaten visar betydelsen av att utföra en fullständig LCA, inklusive framtida tidsperspektiv och bedömning av påverkningskategorier utanför klimatförändringen. Det understryker också förslaget gällamde produktion av elbilar har en betydande ökade oro för elektriska motorer än konventionella bilar. Det finns en risk för miljöproblemförskjutning och ett behovet av att politiska beslutsfattare erkänner befintliga avvägningar. / REFLEX - Analysis of the European energy system under the aspects of flexibility and technological progress
29

State of the Art inom batteriproduktion / State of the Art in battery production

Monteza, Diego, Sakelis, Vitalijs January 2022 (has links)
Denna State of The Art rapport handlar om den senaste elbilsbatteritekniken, batteritillverkning för elbilar, och miljöpåverkan av batterier. Inom elbils batteriteknik förklaras hur dagens batterityper ser ut när det kommer till den kemiska sammansättningen och förklaring på varför de batterityperna är aktuella nu och vilka batterityper som troligtvis blir aktuella i framtiden. Därefter förklaras hur ett elbilsbatteri är uppbyggt, hur komponenterna ser ut idag och hur de kan vidareutvecklas i framtiden. Vidare så skrivs det om hur dagens batterimoduler fungerar. Ytterligare skrivs det om de vanligaste battericellerna som är de cylindriska, prismatiska och påsformade celltyperna. Deras fördelar och nackdelar tas upp. Slutligen finns det en kortfattad beskrivning på vilka dagens största batteritillverkare är och hur marknaden ser ut idag och i framtiden specifikt i Europa. Två företag har analyserats, VDMA och Northvolt. VDMA tillverkar cylindriska, prismatiska och pås batterier. Northvolt tillverkar prismatiska och cylindriska batterier, dessutom tillverkar de batteripack som kan installeras i elbilar. Deras tillverkningstekniker har slagits samman och bildat 5 tillverknings faser. Resultatet ger oss en helhetssyn på hur det går till att tillverka först ett batteri och sedan använda batteriet för att skapa ett batteripack som kan användas i ett elfordon. Vidare så har 3 olika förbättringar inom batteriproduktion tagits upp som resulterat med effektivisering inom produktionssystemet. Slutligen när det kommer till miljöpåverkan av batteritillverkning så anses det vara energikrävande och miljöskadligt. Återvinningsprocessen är komplex och problematisk. Det är billigare att använda nytt råvarumaterial än att använda återvunnen material. Dagens infrastruktur är inte redo för elektrifiering. / This State of The Art report is about the latest electric car battery technology, battery manufacturing for electric cars, and the environmental impact of batteries. In electric car battery technology, it is explained what the current battery types look like when it comes to the chemical composition and an explanation of why those battery types are relevant now and which battery types will probably be relevant in the future. It then explains how an electric car battery is built, what the components look like today and how they can be further developed in the future. Furthermore, it is written about how today's battery modules work. It is also written about the most common battery cells, which are the cylindrical, prismatic and pouch shaped cell types. Their advantages and disadvantages are addressed. Finally, there is a brief description of who today's largest battery manufacturers are and what the market looks like today and in the future specifically in Europe. Two companies have been analyzed, VDMA and Northvolt. VDMA manufactures cylindrical, prismatic and pouch batteries. Northvolt manufactures prismatic and cylindrical batteries, and also manufactures battery packs that can be installed in electric cars. Their manufacturing techniques have merged to form 5 manufacturing phases. The result gives us a holistic view of how it is possible to first manufacture a battery and then use the battery to create a battery pack that can be used in an electric vehicle. Furthermore, 3 different improvements in battery production have been taken up which have resulted in efficiency improvements in the production system. Finally, when it comes to the environmental impact of battery manufacturing, it is considered energy intensive and environmentally harmful. The recycling process is complex and problematic. It is cheaper to use new raw material than to use recycled material. Today's infrastructure is not ready for electrification.
30

En jämförelsestudie av risker och säkerhet mellan elbilar och vätgasbilar / A comparative study of risks and safety between electric cars and hydrogen cars

Anwer, Andri, Boujakly, Edward January 2021 (has links)
Rapporten är skriven för ett högskoleingenjörsexamensarbete på kungliga tekniska högskolan, inom programmet maskinteknik, med inriktning industriell ekonomi och produktion. Bakgrunden av detta arbete ska ge läsaren en grund för de olika modellerna, elbilar och vätgasbilar samt väcka ett intresse för att bevara säkerheten med valet av bil. Syftet och målet med denna studie har varit att presentera en jämförelsestudie, gällande elbilar och vätgasbilar, samt svara på frågeställningarna som arbetet tagit fram. Resultatet av arbetet bygger på både FMEA- analyser för vätgasbilar och elbilar, samt jämförelsematris som ger en förtydligad bild på skillnader mellan elbilar och vätgasbilar, ur vissa valda funktioner. En förtydligad bild av FMEA analysen har byggt, genom att tillämpa ett paretodiagram som beskriver de olika risker och prioritering som finns för respektive modell. Rekommendationer och ytterligare säkerhetsarbeten för att minimera dessa risker beskrivs i FMEA analysen, utifrån indata och beskrivningar från tidigare rapporter, samt kunskap från studier. Resultatet från FMEA- analysen, paretodiagrammet, samt jämförelsematrisen visar att vätgasbilar är en säkrare modell och har en framtid eftersom utvecklingsmöjligheterna fortfarande finns, då dessa är nya på marknaden. Vätgasbilen är även mindre riskbenägen modell jämfört med elbilar, detta kan man visa med hjälp av RPN-talet, som är lägre för vätgasbilar, i jämförelse med elbilarnas RPN-tal. / The background of this thesis will give the reader the basis for the models of electric and hydrogen fueled vehicles. The purpose and goal of this study has been to present a comparative study regarding electric and hydrogen vehicles, and to answer the questions that the study has raised. The results of the work are based on both FMEA analysis for hydrogen and electric vehicles, as well as a comparison matrix that provides a clarified picture of the differences between electric vehicles and hydrogen vehicles, through certain selected factors. A clarified picture of the FMEA analysis results has been built by applying a pareto diagram that describes the different risks of each model and also what their priorities are. Recommendations and additional safety work to minimize these risks are suggested and described in the FMEA analysis, based on input data and descriptions from previous reports, as well as gained knowledge from studies. The results from the FMEA analysis, pareto-diagram and the comparison matrix shows that hydrogen vehicles are a less risk-prone model compared to electric vehicles and have a bright future as development opportunities still exist, this due to the fact that they are still new in the automotive industry. This can be proved with the help of the RPN number for hydrogen vehicles, which is lower compared to the RPN number of electric vehicles.

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