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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.
1

Validation of EcoRouting and an Analysis of the Impact of Traffic on Route Choice

Mysore Shamprasad, Shreyak 15 May 2019 (has links)
Battery Electric Vehicles and Plug-in Hybrid Vehicles are increasingly becoming more popular in recent years. Stricter regulations from government agencies to curb emissions and reduce impact on climate have led to automobile makers adopt electric powertrains. Eco-Routing is one such method to reduce energy usage in personal transport. EcoRouting is a methodology that determines the route with the least energy consumption between two points. Standard navigation systems often determine the shortest or the fastest route, emphasizing travel time. EcoRouting considers an alternative criterion - energy consumption. In this thesis, an automation methodology is presented that determines the EcoRoute among given route alternatives based on route distance, speed limits, road grades, traffic signs, driver aggression and the powertrain. There are three major objectives in this thesis: Developing the automation methodology for the determination of EcoRoute for use in on-board applications, validating the EcoRouting methodology on actual driving conditions and studying the impact of traffic on the choice of EcoRoute. The automation methodology has been developed on the Android framework for use with on-board applications on Android mobile devices. The automation methodology used to conduct sensitivity studies show that factors such as driver aggression, distance and conditional stops impact energy consumption. The comparison of results of simulation using the automation methodology against results from actual driving to validate the methodology on actual driving conditions show that transient traffic conditions can have significant impact on energy consumption. Finally, route energy consumptions for various traffic conditions are estimated using simulation to understand the impact of traffic on energy consumption and EcoRoute choice. Results that are obtained show that apart from traffic affecting the energy consumption, travel times can have an impact on choice of EcoRoute. / Master of Science / Government agencies have been introducing tighter regulations in order to improve fuel economy and reduce emissions. These regulations are targeted at reducing the impact of vehicle usage on climate. Automobile manufacturers have increasingly adopted electric powertrains to meet these regulations. Battery Electric Vehicles and Plug-in Hybrid Vehicles are more popular than ever. Other methods in reducing environmental impact by automobiles are also being conducted. EcoRouting is one such method. EcoRouting determines the route that consumes the least energy between two locations. EcoRouting requires no modifications to be done on the vehicle or its powertrain. A methodology has been developed in this thesis that takes into account various factors such as traffic signs, speed limits, road grades, powertrain and driver aggression to determine the route that consumes the least energy. Research in this thesis has been divided into three major parts: development of the automation methodology, validating the methodology for actual driving conditions and understanding the impact of traffic on energy consumption. Results of case studies show that the input parameters affect energy consumption significantly. Traveling speeds affect the energy consumption and since transient traffic conditions can affect traveling speeds, transient traffic conditions can have a significant impact on energy consumption. Since energy consumption alone is not considered in determining the EcoRoute and the travel times are also considered so as to not inconvenience the user, traffic conditions impact the choice of EcoRoute both due to differences in energy consumption and travel time.
2

Fossil fuel- free by 2030 : A quantitative study on battery electric vehicle adoption and the moderating role of total cost of ownership

Olofsson, Jens, Nymo, Sandra January 2019 (has links)
Battery electric vehicles (BEV) are promoted as a viable near-term technology to reduce the emissions of greenhouse gases (GHG). With Sweden's relatively slow adoption of the BEV in combination with the Swedish government's target of a vehicle fleet independent of fossil fuels by 2030, we study how adoption intentions are influenced by vehicle attribute and when these effects influence BEV adoption. This thesis builds on previous research investigating the effects of barriers and drivers on consumers intentions to adopt electric vehicles. Our study has more specifically examined Swedish consumers intentions to adopt a BEV by conducting a quantitative designed study. We considered the barrier of high perceived price and the driver of environmental self-identity, alongside demographic factors. Furthermore, we also highlight the understudied concept of total cost of ownership (TCO) by studying its moderating role on the relationship between high perceived price, environmental self-identity and consumers intention to adopt BEV’s.  We find that the barrier of high perceived price had no significant influence on intentions to adopt BEV’s, while environmental self-identity was positive and a strong predictor of consumers intentions. Additionally, our results show that the moderating effect of attention to cost (TCOA) and level of information (TCOB) was only significant at one of the four interactions. Concluding that the moderator TCOB has a positive effect on the relationship between high perceived price and intention to adopt BEV’s. These results have implication for BEV marketing, policy and consumers, and suggests that symbolic attributes of the battery electric vehicle have a tendency to reinforce consumers self-identity. This serves as a promising non-financial strategy for increasing BEV adoption. Moreover, the results indicate that consumer with little knowledge of the cost associated with car ownership (low TCOB) are more sensitive to the negative effects from the price of BEV’s in relation to their adoption intentions.
3

Small hauliers' perception of battery electric vehicles : An investigation of opportunities, barriers and potential ownership models

Bohlin, Magdalena, Dahlin, Emma January 2023 (has links)
Today, one third of Sweden’s total greenhouse gas emissions come from domestic transport. To reduce these emissions, the Swedish government has set emission targets. To meet these and to avoid the global impacts of climate changes, the need for new technologies and new fuels to replace fossil fuels has become evident. One of the promising solutions to this is battery-electric vehicles.  The following study has been conducted with Scania, a Swedish truck and bus manufacturer that has chosen to invest more in electricity and today offers a heavy battery-electric truck with a range of 250 km. Today, only large companies have invested in heavy electric trucks while small hauliers, who own no more than ten trucks, are not yet sufficiently motivated to participate in the shift to electrification. Since small hauliers account a large share of freight transport, it is of interest to find out what opportunities and barriers they identify with an investment in battery electric trucks in order to include them in the transition. Furthermore, it is of interest to understand which ownership model can manage the barriers and thus facilitate the adaptation for the small hauliers. Therefore, the purpose of this study was formulated as follows:  To identify what small hauliers perceive as opportunities and barriers with the adoption to BEVs and investigate how they can adapt their ownership models to manage the barriers.  To facilitate the answering of the study’s purpose, it was broken down into research questions and associated sub-questions. Literature was used to create categories for opportunities and barriers: Environmental, Economic and Other for opportunities and Range, Total Cost of Ownership (TCO), Charging and Other for barriers. To answer the research questions, empirical data was collected through structured interviews with small hauliers. The data collected was compiled and analyzed to identify opportunities and barriers. The identified barriers were then used as input together with literature to analyze the ownership models owning, leasing and sharing against the most important barriers.  The findings related to the opportunities was that the small hauliers generally did not see many opportunities apart from reduced air pollution. Improved working environment for drivers was another opportunity mentioned. An increasing number of barriers were identified during the interviews. To summarize the barriers, many were linked to the range of a BEV. The small hauliers’ perceptions are that it is a big challenge to replace refueling with charging in their daily operations. This is based on the lack of natural charging opportunities, but also because there is not enough widespread charging infrastructure in the areas where they carry out their journeys in addition to the fact that the charging itself is too time consuming for the hauliers. Several of the barriers were also linked to the new cost structure with high investment costs and unknown residual value.  The most important barriers could be found in all categories. Of the eight most important barriers, four could be managed by ownership models. It was discussed that many barriers cannot be managed using ownership models but must be addressed in other ways. Of the three ownership models examined, leasing and sharing were able to manage the most barriers, with sharing being able to manage all of them to some extent. By joining a trucking center and sharing vehicles, small hauliers gain advantages enjoyed by larger hauliers, which simplifies their ability to participate in the transformation to electricity. The results indicate that the traditional ownership model, where small hauliers own 100% of their trucks, may not be the way forward to participate in the transition to electricity. The purpose could thus be answered by finding that sharing can manage the most important barriers perceived by small hauliers.
4

The Role of Photovoltaic Generation and Electric Mobility in Future Distribution Systems

Secchi, Mattia 24 October 2022 (has links)
In order to meet the worldwide limits on greenhouse gases emissions, a shift from a fossil fuels to a renewable energy-based electric system is required. As this process goes on, both the power generation and consumption profiles are changing in daily pattern and magnitude, so the power grid needs to become more and more flexible in order to handle this variability. At the distribution level, photo-voltaic (PV) systems are, by far, the most widespread distributed energy resource, mostly due to the recent drop in the cost at the residential level. As more and more consumers become also producers (the so called "prosumers") and the volatile solar energy production increases, a higher number of storage systems is required to both avoid grid destabilisation and minimise the CO$_2$ emissions. At the same time, since the transportation sector is responsible for a sizeable part of the total CO$_2$ emissions, electric vehicles (EVs) are bound to replace traditional internal combustion engine vehicles. However, two main issues may arise when a large number of vehicles are connected to the existing power grid at the same time. The first issue is that the electricity required to charge them needs to be renewable, while the second is that, a rapid electrification of the existing vehicles fleet could destabilise the grid. In this context, this thesis aims at partially addressing these two issues by analysing different ways to reduce the impact of both PV systems and EVs on low (LV) and medium (MV) voltage grids. After the introduction and a chapter dealing with the most closely related research work, a novel optimisation algorithm, aimed at obtaining the optimal storage capacity for each prosumer belonging to a "renewable energy community" is presented. The algorithm minimises the dependence of the community on the main grid, which is one of the main purposes of this new model, while minimising the total installed storage capacity. The algorithm is tailored to the specific case study, because it keeps track of the willingness of the users to install a battery and keeps the voltage levels between regulatory limits in the optimisation process. In the second part instead, the effects of "uncontrolled" and "smart" EV-charging the electric vehicles with the aim of reducing the power fluctuations at the MV/LV transformer level are analysed. In particular, the interaction between PV production and EV charging is investigated, while considering the grid voltage fluctuations, the distribution line losses and the transformer loading levels at the same time. The broader impact of smart charging is also analysed by performing a simplified economic and battery wear analysis. Results help in understanding if storage devices can reduce the dependence of a renewable energy community on the main grid, and to what extent it is possible and economically viable to do so. Moreover, results quantify a realistic range of EV and PV system penetration in a LV grid that still allows for a combined minimisation of their impact on the power grid.
5

Stochastic Power Management Strategy for in-Wheel Motor Electric Vehicles

Jalalmaab, Mohammadmehdi January 2014 (has links)
In this thesis, we propose a stochastic power management strategy for in-wheel motor electric vehicles (IWM-EVs) to optimize energy consumption and to increase driving range. The driving range for EVs is a critical issue since the battery is the only source of energy. Considering the unpredictable nature of the driver’s power demand, a stochastic dynamic programing (SDP) control scheme is employed. The Policy Iteration Algorithm, one of the efficient SDP algorithms for infinite horizon problems, is used to calculate the optimal policies which are time-invariant and can be implemented directly in real-time application. Applying this control package to a high-fidelity model of an in-wheel motor electric vehicle developed in the Autonomie/Simulink environment results in considerable battery charge economy performance, while it is completely free to launch since it does not need further sensor and communication system. In addition, a skid avoidance algorithm is integrated to the power management strategy to maintain the wheels’ slip ratios within the desired values. Undesirable slip ratio causes poor brake and traction control performances and therefore should be avoided. The simulation results with the integrated power management and skid avoidance systems show that this system improves the braking performance while maintaining the power efficiency of the power management system.
6

The need for change : Influencing factors on battery electric vehicles (BEVs) adoption among generation Y within the European market.

Winkler, Martin, Armasu, Alexandru January 2020 (has links)
Background:    Climate change has been becoming a major topic of interest, for research as well as for society. Transport caused emissions are constantly growing which forced the European Union to set the goal to decrease transport related emissions by 60% until 2050. A heavily discussed and promising tool seems to be being found in battery electric (BEV) vehicle adoption. However, BEV adoption seems to be underachieved which raises questions about potential influencing factors on BEV adoption. Additionally, latest research elaborated perception to be one of the key topics of interest for consumers adopting fully electric vehicles. Purpose:           The purpose of this thesis was to examine influencing factors affecting BEV adoption and the perception of those factors among generation Y consumers.  Method:            To attain the purpose, a qualitative research was conducted. After collecting secondary data to evaluate existing factors influencing consumer’s willingness to adopt BEVs, 16 participants accountable to generation Y have been interviewed using semi-structured interviews. Using a qualitative research approach valuable data and in-depth insights which are essential for markets such as the automotive industry. Conclusion:      The results show that there is a generally positive attitude towards BEV adoption among generation Y. However, there have been five influencing factors affecting consumer’s willingness to adopt BEVs. Analysis of the perception of each factor allowed the research team to get in-depth insights and to elaborate the importance of each factor and how the factors interrelate. Based on the gathered data relationships between influencing factors have been highlighted and based on TAM and TRI models a new model for further research has been developed.
7

TECHNOLOGICAL AND ENVIRONMENTAL SUSTAINABILITY OF BATTERY-POWERED ELECTRIC VEHICLES

yang, fan 02 June 2020 (has links)
No description available.
8

Binary choice model for Battery Electric Vehicle : Do solar panels give energy to the choices?

Mats, Gezelius January 2021 (has links)
Energy production is associated with environmental impairment. Most anxious is the greenhouse gas emissions, which also arise from transportation. If battery electric vehicles should be able to alleviate the problem, they must be charged with environmentally friendly produced electricity. This paper investigates a possible relationship between battery electric vehicles and solar photovoltaic panels in household survey data from ENABLE.EU performed in ten European countries autumn 2017 – spring 2018. Estimated with a logit binary choice model, it is found that the probability that a household owns a battery electric vehicle increases if the household owns solar photovoltaic panels. Furthermore, this increase in probability is higher within countries with a higher market diffusion of battery electric vehicle and solar photovoltaic panels (France and the UK). This suggests that policy encouraging home charging of battery electric vehicles from solar photovoltaic panels that includes an energy storage facility could speed up the transition of the vehicle fleet.
9

Evaluation of thermal expansion in busbars used for battery electric vehicles

LARSSON, FREDRIK January 2021 (has links)
Thermal expansion can be an issue in solid busbars, the expansion is caused by several factors and can cause plastic deformation in connection points or structure around it. The expansion occurs due to temperature differences in the busbar as a result of altered ambient temperature and/or joule heating. The environment where a vehicle is used can be harsh and varying in temperatures a lot. For future fast charging systems, a high amount of current will be passed in the conductors. In a stationary installation, this could be solved by increasing the cross-section area. In vehicles, the weight, cost, and space limitations callfor optimization of the conductor. In this thesis, there are several geometrical alterations done to the busbar to investigate the possibility to reduce the amount of stress acting on the connection points. The main geometrical evaluation is to compare a straight busbar to a U-shaped busbar. In the U-shape, the height, bend radius, and cross-section shape are investigated. To investigate this issue a simulation model was developed using Comsol, this software was used to evaluate stress values, max temperature, losses, and displacement. The results from the simulation showed that the U-shape has a large potential to reduce the amount of stress. Also, the cross-section shape tests showed that the steady-state temperature was lower for the more flatter shaped busbar. This is true both for the U-shape and straight busbar. This resulted inreduced amount of thermal expansion causing lower amount of stress, without adding any weight. The weight parameter is extremely important for vehicle implementation. The last test is looking at the busbar material where nickel-plated copper is compared to anodized aluminum. This test is divided into two parts, the first one is looking at an aluminum busbar compared to a copper busbar of the same geometry. This test showed that the losses in the aluminum busbar were much higher, but the steady-state temperature and max stress were lower. The second part of the test investigated the compensated aluminum busbar, this one is modeled by compensating the cross-section area for the higher resistance value of aluminum. The results from this busbar compared to the standard-shaped busbar showed a substantially lower stress, temperature and weight. But the overall dimensions are larger due to the compensated cross-section area. Having this larger Cross section area might hinder the implementation of aluminium busbars in parts of the vehicle where there is a lack of space, like in a battery box. / Termisk expansion i solida busbars är ett vanligt problem vid kraftig temperaturvariation. Problemet ökar med längden av busbaren och kan leda till plastisk deformation i infästningen av busbaren. Temperaturvariationen kan ske genom varierad omgivningstemperatur eller genom resistiv uppvärmning. Om en busbar ska användas i ett fordon för kraftöverföring är arbetsmiljön mycket påfrestande. Den termiska uppvärmningen går normalt att motverka genom att öka tvärsnittsarean, men i ett fordon där vikt, kostnad och platsbrist minskar möjligheten för ökad tvärsnittsarea blir optimering av ledaren extra viktig. För att undersöka problemet utvecklades en simuleringsmodell med hjälp av Comsol. Denna programvara använder för att utvärdera spänningskoncentrationer, maxtemperatur, förluster och utböjningar i busbaren. För att undersöka eventuella lösningar togs det fram flera geometriska variationer till busbaren, där möjligheten att använda en “U-form” utgjorde basen i en jämförelse mot en vanlig rakbusbar. För U-formen undersöktes U-höjden, böj-radien samt tvärsnittsformen. Även en jämförelse mellan nickelpläterad koppar och anodiserad aluminiumgenomfördes för att urskilja eventuella för och nackdelar med materialen. Resultaten från simuleringarna visade att U-formen gav klart lägre spänning i kontaktpunkterna. Även tvärsnittsformen påverkade temperaturen och spänningen i busbaren, där den plattare varianten presterade bättre på alla parametrar som undersöktes i simuleringen. För utvärderingen av materialet utfördes två tester, det första testet jämför en busbar i aluminium mot en i koppar med exakt samma geometri, detta testvisade att temperaturen samt spänningen blir lägre i aluminiumvarianten, dock ökar förlusterna kraftigt då aluminium har högre resistans än koppar. I den andra testet användes en kompenserad aluminiumbusbar där tvärsnittsarean har ökats för att ge samma resistans som kopparvarianten. Denna busbar fick en mycket lägre sluttemperatur, spänning och vikt. Förlusterna blev detsamma. Den högre tvärsnittsarean ger dock en fysiskt större busbar.
10

An Analysis of EcoRouting Using a Variable Acceleration Rate Synthesis Model

Warpe, Hrusheekesh Sunil 07 August 2017 (has links)
Automotive manufacturers are facing increasing pressure from legislative bodies and consumers to reduce fuel consumption and greenhouse gas emissions of vehicles. This has led to many automotive manufacturers starting production of Plug-in Hybrid Electric Vehicles (PHEV's) and Battery Electric Vehicles (BEV's). Another method that helps to reduce the environmental effect of transportation is EcoRouting. The standard Global Positioning System (GPS) navigation offers route alternatives between user specified origin and destination. This technology provides multiple routes to the user and focuses on reducing the travel time to reach to the destination. EcoRouting is the method to determine a route that minimizes vehicle energy consumption, unlike traditional routing methods that minimize travel time. An EcoRouting system has been developed as a part of this thesis that takes in information such as speed limits, the number of stop lights, and the road grade to calculate the energy consumption of a vehicle along a route. A synthesis methodology is introduced that takes into consideration the distance between the origin and destination, the acceleration rate of the vehicle, cruise speed and jerk rate as inputs to simulate driver behavior on a given route. A new approach is presented in this thesis that weighs the energy consumption for different routes and chooses the route with the least energy consumption, subject to a constraint on travel time. A cost function for quantifying the effect of travel time is introduced that assists in choosing the EcoRoute with an acceptable limit on the travel time required to reach the destination. The analysis of the EcoRouting system with minimum number of conditional stops and maximum number of conditional stops is done in this thesis. The effect on energy consumption with the presence and absence of road-grade information along a route is also studied. A sensitivity study is performed to observe the change in energy consumption of the vehicle with a change in acceleration rates and road grade. Three routing scenarios are presented in this thesis to demonstrate the functionality of EcoRouting. The EcoRouting model presented in this thesis is also validated against an external EcoRouting research paper and the energy consumption along three routes is calculated. The EcoRoute solution is found to vary with the information given to the variable acceleration rate model. The synthesis and the results that are obtained show that parameters such as acceleration, deceleration, and road grade affect the overall energy consumption of a vehicle and are helpful in determining the EcoRoute. / Master of Science

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