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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

Comparing technologies and algorithms behind mapping and routing APIs for Electric Vehicles

Andreasson, Erik, Axelsson, Amanda January 2020 (has links)
The fast-developing industry of electric vehicles is growing, and so is the driver community, which puts pressure on the electric charging grid. The purpose of this thesis is to simplify for the drivers of electric cars to charge their cars during trips. The research questions investigated are” How do the technologies and algorithms behind navigation APIs differ from each other?” and “What information is provided by the charging station APIs and how do they collect data about new stations?”. Information for the thesis was collected by reading and analyzing both documentation and previous work, as well as by conducting experiments. The study was limited to purely electric vehicles. We created an application to conduct experiments on the API combination Mapbox and Open Charge Map, we call it ChargeX. We compare, TomTom, Tesla, Plugshare, Google Maps and ChargeX. The most common shortest-path algorithms are Dijkstra’s, A* and Bidirectional A*. They provide reasonable solutions to the shortest path problem. The algorithms can be improved by considering traffic flow, travel time and distance between origin and destination and apply it as weights on the edges. What has the largest impact on the final route is the choice of charging stations. The algorithm for picking charging stations can be optimized in several ways for example by considering real time availability information of the charging stations, prioritize highways, calculate the temperature and altitude impact on the battery or prioritize faster chargers such as superchargers for Tesla.
402

Implementation of HomePlug Green Phy standard (ISO15118) into Electric Vehicle Supply Equipment

Pallander, Rama January 2021 (has links)
As the use of electric vehicles increases, the need for electric vehicle supply equipment to have more advanced functionality also increases. The HomePlug Green PHY standard was developed to allow more advanced communication between electric vehicles and electric vehicle supply equipment. This more advanced form of communication can solve problems such as load balancing during busy charging and seamless payment methods. There are some modem solutions that are based on the Qualcomm QCA7000 chip that allows for implementation of the HomePlug Green PHY standard.             This thesis explores and highlights the implementation of the hardware for the HomePlug Green PHY standard into a solution that is nearly plug and play for most electric vehicles. A module in the form of a PCB based around one of these modem solutions is developed that allows modular expansion of a traditional electric vehicle supply equipment to gain the functionality of HomePlug Green PHY. The final PCB is a near plug and play solution on the hardware side however, the software needs further development.
403

Application of Sustainable Development Concept as a Factor of International Competitiveness / Application of Sustainable Development Concept as a Factor of International Competitiveness

Kolmosová, Lucia January 2017 (has links)
Tato diplomová práce se zaměřuje na aplikaci koncepce udržitelného rozvoje ve firmě Volkswagen Slovakia na posílení její konkurenceschopnosti. Automobilová společnost je analyzována jako hráč v odvětví udržitelné mobility a její současná strategie je zhodnocena v zmyslu udržitelnosti. Na základě nejrelevantnějších aspektů analytické části je navržena řada doporučení, které by měli podpořit působení firmy v oblasti výroby elektrických vozidel a poskytování transportních služeb a které by měli přispět k dosažení eko-konkurenční výhody v daném odvětví.
404

GHG EMISSION COMPARISON BETWEEN E85 FLEX FUELVEHICLE AND EV UPTAKE : A Scandinavian perspective

Dewilde Cervelló, Lucas January 2021 (has links)
In this thesis the effects of two future greenhouse gas emissionreducing strategies in the passenger transport sector are investigated.Three factors were modelled for 2021-2055; The life cycle emissions offour vehicle types using a well-to-wheel life cycle analysis tool calledGREET, the growth curve of these vehicle types was analyzed andextrapolated to obtain total vehicle predictions and the mileage ofthese vehicles was extrapolated from existing governmental data. Theresulting scenarios show that in the short term E85 ex fuel vehicles arecapable of more avoided emissions, with EVs outperforming them inthe long term. However limitations in the prediction of vehicle mileageleaves the overtake point to be determined.
405

Bewertung integrierter Mobilitätsdienste mit Elektrofahrzeugen aus Nutzerperspektive: Ergebnisse der Begleitforschung im Projekt BeMobility – Berlin elektroMobil

Hoffmann, Christian, Graff, Andreas, Kramer, Steffi, Kuttler, Tobias, Hendzlik, Manuel, Scherf, Christian, Wolter, Frank 14 January 2020 (has links)
Projekt BeMobility: Carsharing mit e-Fahrzeugen Ziel war die Einbindung von Elektroautos in eine Carsharing- Flotte und ihre Integration in multimodale Angebotskonzepte. Nutzergerechte Mobilitätsangebote für urbane Räume wurden entwickelt und im Realbetrieb beurteilt; hierbei wurde die Attraktivität des Carsharing mit e-Autos untersucht. (Kapitel 1) Forschungsansatz: Feldtest mit multimethodaler Begleitforschung Die angewandte Forschung des InnoZ setzte auf eine Kombination verschiedener Methoden. Sowohl vor als auch während des Feldtests wurden potenzielle Nutzer bzw. Testkunden befragt. Dazu wurden die Methoden Lead-User-Integration, Fokusgruppen sowie breite Befragungen gewählt. (Kapitel 2) Interessenten und Testkunden: Männlich, gebildet und ÖV-affin Potenzielle Nutzer und Testkunden sind den sozialen Leitmilieus zuzuordnen. Sie können als sogenannte Lead User gelten. Die Begleitforschung mit über 500 Befragten in vier Teilstudien lässt wichtige Schlüsse auf Akzeptanz und zukünftige Verbreitung von e-Autos im Carsharing zu. (Kapitel 3) Elektrofahrzeuge: Hoher Fahrspaß, aber Reichweite kritisch Die Erwartungen potenzieller Nutzer aus der Vorfeldphase werden im Praxistest teilweise übertroffen. Dies gilt insbesondere für die Fahreigenschaften der Elektrofahrzeuge. Allerdings werden die Erwartungen an Batterie und Laden sowie speziell an die Reichweite nicht erfüllt. (Kapitel 4) Preisbeurteilung: Geringe Aufpreisbereitschaft für e-Carsharing Für elektrisch betriebene Fahrzeuge gibt es auch im Carsharing- Einsatz kaum eine Aufpreisbereitschaft. Für ausgewählte zusätzliche Services besteht auf Nutzerseite aber eine – wenn auch geringe – ergänzende Zahlungsbereitschaft. (Kapitel 5) Mobilitätskarte: Multimodales Angebot gut bewertet Die befragten Nutzer sehen die Kombination von e-Fahrzeugen mit dem öffentlichen Verkehr als wichtig an. Eine Mobilitätskarte, die eine Nutzung von Flinkster, Call a Bike und ÖPNV ermöglichte, wurde im Feldtest positiv bewertet. (Kapitel 6) Akzeptanz: Hohe Kundenbindung, aber geringe Nutzung Die Testnutzer haben eine hohe emotionale Kundenbindung. Diese wurde aber im Regelfall nicht in eine entsprechend häufige Nutzung der Fahrzeuge umgesetzt. Vielnutzer beurteilten die Dienstleistung e-Carsharing signifikant besser als die große Gruppe der Wenignutzer. (Kapitel 7) Mobilitätstypen: Öko-Überzeugte und ÖV-Affine mit Potenzial Auf Basis des Mobilitätstypenansatzes wurde die Stichprobe der potenziellen e-Carsharing-Kunden in verschiedene Typen aufgeteilt. Die höchsten Potenziale ergaben sich bei den Typen „ökologisch überzeugte Radfahrer und Multimodale“ und „pragmatisch orientierte ÖV-Nutzer“. (Kapitel 8) / The BeMobility Project: Car-sharing with Electric Vehicles The aim of the project was the insertion of e-vehicles into a carsharing fleet and its subsequent integration with multi-modal public transport offerings. User-friendly urban mobility services were developed and evaluated under real-world conditions. The attractiveness of integrating e-vehicles into an existing car-sharing service was investigated. (Chapter 1) Methodology: Field Trials and Multi-Method Market Research Potential users and customers were interviewed before and during the field trials. In addition, methods such as “lead-user integration”, focus groups, as well as a general survey of user attitudes were chosen. (Chapter 2) Interested Users and Pilot Customers: Male, Highly-Educated, with an Affinity to Public Transport Potential users and customers generally belong to social groups A/B and can be considered ‘lead-in’ users. The survey of more than 500 users in 4 separate market research studies yielded important insights regarding user acceptance and the future spread of e-vehicles in car-sharing fleets. (Chapter 3) E-Vehicles: Positive Driving Experience but Range is Critical Some expectation of potential users from the pre-trial phase were met or even over-fulfilled. This is true in particular with regards to the driving experience associated with e- vehicles. However, the expectation of users with regard to batteries, charging and, specifically, the range of e-cars were not met. (Chapter 4) Pricing Expectations: Low Acceptance of Surcharges for eCar-Sharing There is very low user acceptance of premium pricing for e-vehicles even when they are deployed as part of a car-sharing service. There was some, but relatively low willingness to pay for additional electric mobility services amongst users. (Chapter 5) Smart Mobility Card: Positive User Response to Multi-Modal Services Offerings The users that were surveyed view the combination of e-vehicles with public transport as important. A smart mobility card, which integrated flat-rate access to the Flinkster e-car-sharing service, the Call-a-Bike service and public transport were positively evaluated in the field trials. (Chapter 6) User Acceptance: Emotional Affinity – Low-Frequency Service Use The test users displayed a strong emotional affinity to the mobility service offerings. Routine, high-frequency users judge the electric car-sharing services significantly more positive than the bigger group of low-frequency users. (Chapter 7) User Characteristics: Green Values and Public Transport Affinity Indicate Potential A sample of car-sharing clients was surveyed. The highest user potential was documented in user types “green-conscious cyclists and multi-modal users” and “pragmatic public transport users”. (Chapter 8)
406

Wie bist Du in der Stadt unterwegs?: Mobilität junger Menschen in eigenen Bildern und eigenen Worten – Ergebnisse einer Explorationsstudie

Deibel, Inga, Schelewsky, Marc, Schönduwe, Robert 14 January 2020 (has links)
Seit einigen Jahren wird spekuliert, dass eine neue Generation heranwächst, die das eigene Auto nicht mehr unhinterfragt als Grundausstattung des modernen Menschen versteht, sondern ihre Mobilität effektiver und nachhaltiger gestaltet. Steuern wir also auf eine schöne neue Mobilitätswelt zu? Diese Schlussfolgerung zu ziehen wäre angesichts der Vorläufigkeit der Befunde und der unsicheren empirischen Basis der Aussagen voreilig. Um die Debatten zur Mobilität junger Menschen zu versachlichen und Einblick in die Komplexität der Wirkungszusammenhänge zu gewinnen, führte das InnoZ im Jahr 2012 eine empirisch-qualitative Explorationsstudie durch. Die Ergebnisse dieser Studie sind in Form eines Werkstattberichts im vorliegenden Baustein dokumentiert. Trotz vieler offener Fragen belegen die Ergebnisse der Studie, dass ein Wandel von Mobilitätsmustern junger Menschen möglich ist, aber kein Selbstläufer sein wird. Die Schüler nutzen die zur Verfügung stehenden Verkehrsmittel bedürfnisorientiert und sind dabei offen für die Kombination unterschiedlicher Verkehrsmittel. Eines ist jedoch auch deutlich geworden: Junge Menschen kennen die neuen Alternativen noch zu wenig. In den Gesprächen rund um neue Angebotsformen wie Carsharing und Elektromobilität wurde deutlich, dass sich junge Menschen erst dann mit den Optionen auseinandersetzen, wenn diese für die eigene Mobilitätsbewältigung in Betracht kommen. Zwei Ergebnisse der Explorationsstudie sollten zukünftig stärker beachtet werden. Erstens existieren bei den meisten Befragten weder Vorbehalte gegenüber Alternativen zum privaten Pkw noch monomodale Fixierungen. Wichtig ist den jungen Menschen nicht der eigene Pkw, sondern vielmehr Unabhängigkeit und Flexibilität. Wenn dies mittels geteilter Nutzung von Pkw oder anderer alternativer Verkehrsmittel realisiert werden kann, so spielt das Auto in den Augen nahezu aller Teilnehmer keine exklusive Rolle mehr. Wenn es keine entsprechenden Alternativen gibt, ist das eigene Auto jedoch nach wie vor das Maß aller Dinge. Junge Menschen sind grundsätzlich offen für alle zur Verfügung stehenden Angebote − dies zeigt die Explorationsstudie deutlich. Sie müssen nur bekannt, einfach zu nutzen, schnell, flexibel und kostengünstig sein. Das Smartphone scheint dabei eine wichtige Funktion zur Organisation der eigenen Mobilität einzunehmen. Zweitens wurde deutlich, dass junge Menschen in der Begründung ihrer Verkehrsmittelwahl primär auf begrenzte Budgets verweisen. Ein Verkehrsmittel sollte folglich nicht nur Unabhängigkeit und Flexibilität gewährleisten, sondern es sollte in den Augen der jungen Menschen vor allem nicht allzu viel Kosten verursachen. Es sollten folglich nicht nur neue Mobilitätsangebote entwickelt werden, sondern auch attraktive Tarifsysteme, die es erlauben, die Zahlungsbereitschaft der jungen Menschen möglichst optimal zu adressieren. / Young people’s mobility patterns are changing. They no longer regard the private car as a basic need of the modern human being. This hypothesis has been the subject of debate for several years. Following this argument, it seems that the young generation is moving along a more sustainable path. Are we heading for a brave new world of transport? Drawing this conclusion would be too hastily. The empirical basis is too shallow and findings are still preliminary. In 2012, the InnoZ conducted an explorative study on youth mobility to display the complexity of the topic and channel the debate. Results of this study are documented in this working paper. Despite many unanswered questions, the study shows that although a change of mobility patterns of young people is possible it will be anything but self-propelled. Young people use available transport modes according to their needs and are open towards an efficient combination of different means of transport. However, the study additionally showed that young people are still not sufficiently aware of new alternatives. Discussions with teenagers uncovered that new mobility services like carsharing and electric vehicles only become a relevant issue if regarded as practical options for their everyday mobility. Two results of the explorative study should be considered in future research. Firstly, most interviewees neither expressed reservations about alternatives to the private car nor demonstrated a fixed orientation towards a single mode type. It isn’t the private car that is important to young people but rather independence and flexibility. If alternative mobility services provide those attributes, the private car and its alternatives are not mutually exclusive. Basically, young people are open to all accessible options – this can be derived quite clearly from our study. Nevertheless, car ownership still constitutes the measure of all things if there’s a lack of alternatives. Our study also revealed that the smartphone seems to play an important role for the organisation of young people’s individual mobility. Secondly, young people tend to decide on their means of transport in context of their − usually limited − budgets. Consequently, new mobility services should ensure not only independence and flexibility, but above all have to be affordable. When developing new mobility services, young people’s willingness to pay should be addressed by implementing attractive fares and charging systems.
407

Proposal of wireless charging method and architecture to increase range in electric vehicles

Omar Nabeel Nezamuddin (10292552) 06 April 2021 (has links)
<div>Electric vehicles (EVs) face a major issue before becoming the norm of society, that is, their lack of range when it comes to long trips. Fast charging stations are a good step forward to help make it simpler for EVs, but it is still not as convenient when compared to vehicles with an internal combustion engine (ICE). Plenty of infrastructure changes have been proposed in the literature attempting to tackle this issue, but they typically tend to be either an expensive solution or a difficult practical implementation.</div><div> </div><div> This dissertation presents two solutions to help increase the range of EVs: a novel wireless charging method and a multi-motor architecture for EVs. The first proposed solution involves the ability for EVs to charge while en route from another vehicle, which will be referred to from here on as vehicle-to-vehicle recharging (VVR). The aim of this system is to bring an innovative way for EVs to charge their battery without getting off route on a highway. The electric vehicle can request such a service from a designated charger vehicle on demand and receive electric power wirelessly while en route. The vehicles that provide energy (charger vehicles) through wireless power transfer (WPT) only need to be semi-autonomous in order to ``engage'' or ``disengage'' during a trip. Also, a novel method for wireless power transfer will be presented, where the emitter (TX) or receiver (RX) pads can change angles to improve the efficiency of power transmission. This type of WPT system would be suitable for the VVR system presented in this dissertation, along with other applications.</div><div> </div><div> The second solution presented here will be an architecture for EVs with three or more different electric motors to help prolong the state of charge (SOC) of the battery. The key here is to use motors with different high efficiency regions. The proposed control algorithm optimizes the use of the motors on-board to keep them running in their most efficient regions. With this architecture, the powertrain would see a combined efficiency map that incorporates the best operating points of the motors. Therefore, the proposed architecture will allow the EV to operate with a higher range for a given battery capacity.</div><div> </div><div> The state-of-the-art is divided into four subsections relevant to the proposed solutions and where most of the innovations to reduce the burden of charging EVs can be found: (1) infrastructure changes, (2) device level innovations, (3) autonomous vehicles, and (4) electric vehicle architectures. The infrastructure changes highlight some of the proposed systems that aim to help EVs become a convenient solution to the public. Device level innovations covers some of the literature on technology that addresses EVs in terms of WPT. The autonomous vehicle subsection covers the importance of such technology in terms of safety and reliability, that could be implemented on the VVR system. Finally, the EV architectures covers the current typologies used in EVs. Furthermore, modeling, analysis, and simulation is presented to validate the feasibility of the proposed VVR system, the WPT system, and the multi-motor architecture for EVs.</div>
408

Current harmonic modeling of aggregated electric vehicle loads in the low voltage grid

Foskolos, Georgios January 2021 (has links)
The proliferation of Electric Vehicles (EVs) poses new challenges for the Distribution System Operator (DSO). For example, the rectifiers that are used for charging EV batteries could significantly influence Power Quality (PQ), in terms of harmonic distortion. The emissions from individual EV, are well regulated by current harmonic emission standards. But what the aggregation of multiple EV loads will look like is still uncertain and the research being made in this area is still in its early stage.  The DSO responsibilities include ensuring grid code compliance confirmed by PQ metering.  In general, 10 minute RMS values are sufficient. However, the large scale integration of non-linear loads, like EVs, could lead to new dynamic phenomena, possibly lost in the process of time aggregation. In this thesis PQ and, in more detail, the concept of harmonics, and how this is related to EVs, is presented. A current-harmonic load model using power exponential functions and built from actual measurement data during the individual charging of four different fully electric vehicles was constructed. The model was based on individual emitted current harmonics as a function of state of charge (SOC), and was used to deterministically simulate the simultaneous charging of six vehicles fed from the same bus. The aggregation of current harmonics up to the 11th was simulated while randomizing battery SOC, the start of charging, and the kind of vehicle. Additionally, an investigation of the impact on aggregation in time was conducted. The analysis clearly shows the importance of phase angle information, its correlation to SOC, and how the aggregation of EV loads is influenced by these factors. The analysis also shows that 10 minute RMS aggregation could lead to significant deviations from the “actual” (200ms) data.  This indicates that 10 minute value monitoring could lead to information losses.
409

Stockholm som elbilsstad 2030 / Stockholm 2030 - A  City of Electric Cars

Bernhardsson, Fredrik, Grill, Peter January 2011 (has links)
I Sverige används det idag cirka 5,4% förnybara drivmedel inom transportsektorn, att jämföra med under 0,5% år 2000. Av de ickefossila drivmedlen är el något som ofta benämns som en permanent och realistisk framtida lösning. Visionen ”Stockholm – Elbilsstad 2030” drivs av Stockholms Stad i samarbete med Fortum AB i syfte att ersätta den fossilbränsleslukande fordonsflottan. I den här studien undersöks de tekniska förutsättningarna och de eventuella vinsterna av ett storskaligt införande av elbilar. Studien har gjorts genom en modellering där parametrar som elbilens prestanda, elpris, bilens inköpspris och totala utsläpp använts. Resultatet skall presentera ett mikro- och ett makroresultat. Vinsterna beräknas dels för den enskilde individen, men också för samhället i stort. Vinsterna beräknas med en känslighetsanalys baserad på reella framtida scenarier. Resultaten visar tydligt att för den genomsnittlige Stockholmaren är elbilen det mest ekonomiskt lönsamma valet på sikt. På tio års sikt beräknas bensinbilen kosta individen 65,93% mer än elbilen om bensinpriset fortsätter med samma utveckling. En känslighetsanalys visar att även om bensinpriset skulle sjunka med 5% årligen in i framtiden skulle bensinbilen ändå vara 31,3% dyrare på tio års sikt. Resultaten visar också att samhällets kostnader för bilflottans utsläpp förväntas sjunka med 98% eller 92% beroende på om den svenska elproduktionen är tillräcklig eller om man måste importera el från övriga Norden. Samtidigt som kostnaderna för utsläppen sjunker för samhället, sjunker även skatteintäkterna till följd av minskad bensinanvändning. Om elpriset på sikt skulle stiga till följd av en ökad användning skulle detta dock kunna leda till att förlusten reduceras. Klart är att storskaligt införande av elbilar kräver ett engagemang från staten där den ekonomiska förlusten får ses som en investering i miljön och framtiden. / In Sweden there are currently about 5.4% renewable fuel vehicles within the transport sector, compared to less than 0.5% in 2000. Amongst the non-fossil fuel alternatives electricity is something which has often been referred to as a permanent and realistic future solution. The vision “Stockholm – A City of Electric Cars in 2030" is run by the City of Stockholm in cooperation with Fortum AB in order to replace the fossil-fuel-guzzling fleet. This report examines the technical conditions and possible gains of a large scale introduction of electric cars. The study was conducted through a modelling in which parameters such as electric car performance, tariff and total emissions are used. The conclusion will reveal a micro- and macro result. Economic gains are calculated both for the individual, but also for society at large. The profits are calculated by a sensitivity analysis based on realistic future scenarios. The results clearly show that for the average Stockholm resident, the electric car is the most economical choice. In ten years time the gasoline car is expected to cost the individual 65.93% more than the electrical car based on that the price of gasoline continues its current growth. A sensitivity analysis shows that even if gasoline prices were to drop by 5% annually into the future, gasoline car would still be 31.3% more expensive than the electric car in ten years time. The results also show that the societal costs of the car fleet’s emissions are expected to fall by 98% or 92% depending on whether the Swedish electricity production is sufficient, or whether imported electricity from other Nordic countries is necessary. While the cost of emissions decreases for the society, so are tax revenues due to reduced gasoline use. However, if the electricity price in the long run would rise due to increased use, this could however lead to a reduction of the loss. It is clear that for a large-scale introduction of electric cars to be successful it requires a committed government which will have to see the economic loss as a means to investment in the future and the environment.
410

Location planning for electric charging stations and wireless facilities in the era of autonomous vehicle operations

Amir Davatgari (10724118) 29 April 2021 (has links)
This thesis proposes a planning framework for Autonomous Electric Vehicle (AEV) charging. The framework is intended to help transportation decision-makers determine Electric Vehicle (EV) charging facility locations and capacities for the mixed fleet of Autonomous Vehicle (AV) and Human-driven Vehicle (HDV). The bi-level nature of the framework captures the decision-making processes of the transportation agency decision-makers and travelers, thereby providing solid theoretical and practical foundations for the EV charging network design. At the upper level, the decision-makers seek to determine the locations and operating capacities of the EV charging facilities, in a manner that minimizes total travel time and construction costs subject to budgetary limitations. In addition, the transportation decision-makers provide AV-exclusive lanes to encourage AV users to reduce travel time, particularly at wireless-charging lanes, as well as other reasons, including safety. At the lower level, the travelers seek to minimize their travel time by selecting their preferred vehicle type (AV vs. HDV) and route. In measuring the users delay costs, the thesis considered network user equilibrium because the framework is designed for urban networks where travelers route choice affects their travel time. The bi-level model is solved using the Non-Dominated Sorting Genetic Algorithm (NSGA-II) algorithm.

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