The municipal company Sportfastigheter AB is currently renovating and developing Gränby sportfält, a sports field in Uppsala. Adjacent to the sports field, a parking lot for 700 vehicles is located, where Sportfastigheter AB is preparing to install charging points for electric vehicles (EVs) at some of the places. This bachelor thesis aims to investigate how a public charging solution should be modeled, with the parking lot at Gränby sportfält as a case study. The investigation involves estimating energy demand of visiting EVs, optimizing the ability to satisfy the estimated energy demand, and proposals of business models. A computer-based simulation of a representative week at Gränby sportfält was created as a decision basis for modeling the charging solution and what power capacity to dimension for. The results of this investigation indicates that the most suitable charging solution for Gränby sportfält is a solution with semi-fast chargers and load balancing, which is a type of controlled charging. With load balancing, a lower power capacity can be dimensioned for compared with the same solution without load balancing with savings in costs as a consequence. When investigating for 50 charging points the power capacity proposed to dimension for is 200 kW, which would lead to the possibility of meeting 98.7 % of the total energy demand of connected EVs. However, this study proposes to build the charging points gradually, with an initial installation of 12 charging points. Lastly, this study proposes to use a business model involving sponsoring, and offer the charging for free.

abstract: Transmission line capacity is an obstacle for the utilities because there is a load increment annually, and new power plants are being connected, which requires an update. Energy router (ER) is a device that provides an additional degree of freedom to the utilities by controlling the reactive power. The ER reactive power injection is demonstrated by changing the line's reactance value to increase its capacity and give the utility a deferral time for the project upgrade date. Changing the reactance manually and attaching Smart Wire's device to the branches have effectively solved the overload in three locations of a local utility in Arizona (LUA) system. Furthermore, electric vehicle charging stations (EVCSs) have been increasing to meet EV needs, which calls for an optimal planning model to maximize the profits. The model must consider both the transportation and power systems to avoid damages and costly operation. Instead of coupling the transportation and power systems, EVCS records have been analyzed to fill the gap of EV demand. For example, by accessing charging station records, the moment knowledge of EV demand, especially in the lower order, can be found. Theoretically, the obtained low-order moment knowledge of EV demand is equivalent to a second-order cone constraint, which is proved. Based on such characteristics, a chance-constrained (CC) stochastic integer program for the planning problem is formulated. For planning EV charging stations with ER, this method develops a simple ER model to investigate the interaction between the mobile placement of power flow controller and the daily pattern of EV power demand. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2020

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Background: Due to the escalated environmental concerns and the requirement of Paris Agreement, restraining the carbon emission is aimed on a global scale. Being a solution, the electrification of vehicles is inevitable whilst the problematization to the batteries continues. Many strategies, from improving the battery default as a product, to servitizing the batteries in the light of servitization, has been attempted by both battery suppliers and car manufacturers. In connection to sustainability concerns, which refers to the battery End-of-Life (EoL) Management, however, not many scholars believe that circular economy for electric vehicle batteries can shape itself. Deeming the massive adoption of electric vehicle as the foundation of circular economy, some scholars advocate, that servitization can propel the execution of sustainable goal when it changes the ownership of batteries from customers to manufacturers.  Purpose: The proposed relationship of battery servitization and sustainability is standing alone shortly since 2020 without much evidence support. Hence, it is put on the list of examination to identify the motives and interest of manufacturers by offering battery servitization. Moreover, owing to the fact that the literature of battery servitization is seen segmented for only single dimensioned service type, it is also aimed by this thesis to coin the status-of-art of battery servitization from the empirical study, with customers’ perspective included.  Methodology: This thesis is designed based on a mixed method including qualitative interviews and quantitative surveys to answer the research questions that none of the methods could answer alone. Both inductive and deductive approaches were adopted due to the discrepant results from the empirics. Particularly, triangulation design, obtaining different yet complementary data to study the same topic, is followed to structure the discussion.  Findings & Conclusion: Generally, the findings answer the purpose of writing this thesis well. From qualitative study, battery servitization is more of a marketing strategy and not after a goal of building the circularity. However, sustainability is deployed by manufacturers of all levels in the supply chain. Additionally, Battery-as-a-Service (BaaS) as an all-round service solution is enlarging the content to servitize. Further, not being much aware of though, battery servitization is enabling the circularity of batteries owing to the respective battery strategies of each manufacturer. This is to say, sustainability is considered in combination of battery servitization, as the theoretical base of this thesis suggests. From quantitative study, customers’ satisfaction level proves that the manufacturers’ aimed goal is partly achieved. However, to use battery servitization as a marketing strategy for electric vehicle adoption, which indirectly facilitate sustainability, it should be invested more efforts to help more potential customers accept it.

There are various technologies used for reducing fuel consumption of automobiles. Hybrid electric vehicles is one approach that has been used, which can reduce fuel consumption by 10-30% compared to conventional vehicles. In this master thesis the minimization of fuel consumption of a power-split type HEV along a given route is considered, where the vehicle speed has been assumed to be known a priori. This minimization was made by first deriving a model of the HEV powertrain, followed by creating a Dynamical programming based program for finding the optimal distribution of torques. The performance was evaluated through the commercial software GT-Suite. The resulting control from the Dynamic program could follow the reference speed in many situations. However the battery state-of-charge calculated in the Dynamic program did not update properly, resulting in a depleted battery in some cases. The model derived could follow the dynamics of the vehicle, but there are some parts which could be improved. One of them is the dynamical model of the rotational speed for the engine <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Comega_%7Be%7D" />.  The Dynamic program works for finding the controller, and can be modified to work with improved state-equations. / Det finns olika sätt att minska bränsleförbrukningen hos bilar, men ett sätt som använts är el-hybrider. Dessa kan minska bränsleförbrukningen med 10-30% jämfört med konventionella bilar. I det här examensarbetet undersöks optimering av bränsleförbrukning för en el-hybrid, där hastigheten antas vara känd i förväg. Optimeringen skedde genom att först härleda en modell för drivlinan, och därefter skapades ett Dynamisk programerings baserat program för att hitta den optimal kombinationen av moment. Bränsleförbrukning och prestanda jämfördes genom programvaran GT-Suite. Dynamiska programmeringen gav lovande resultat som följde referenshastigheten i många fall. Däremot uppdaterades inte laddningen för batteriet lika bra, vilket ledde till att batteriet i vissa fall blev urladdat. Modellen som härleddes visade i många fall liknande respons som GT-Suite, men viss förbättring kan ske. En utav dessa förbättringar är rotationsekvationen för bränslemotorn, <img src="http://www.diva-portal.org/cgi-bin/mimetex.cgi?%5Comega_%7Be%7D" />. Den Dynamiska programmeringen som skapades fungerade, och kan modifieras för förbättrade tillståndsekvationer

Modern hybrid electric and pure electric vehicles are highly dependent on control algorithms to provide seamless safe and reliable operation under any driving condition, regardless of driver behavior. Three unique and independently operating supervisory control algorithms are introduced to improve reliability and vehicle performance on a series-hybrid electric vehicle with an all-wheel drive all-electric drivetrain. All three algorithms dynamically control or limit the amount of torque that can be delivered to the wheels through an all-electric drivetrain, consisting of two independently controlled brushless-direct current (BLDC) electric machines. Each algorithm was developed and validated following a standard iterative engineering development process which places a heavy emphasis on modeling and simulation to validate the algorithms before they are tested on the physical system. A comparison of simulated and in-vehicle test results is presented, emphasizing the importance of modeling and simulation in the design process.

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.

This thesis presents changes to the design of the Prototype Vehicles Laboratory (PROVE Lab) Endurance Car, an electric car intended to break the Guinness World Record for the single-charge range of an electric vehicle. The design range is 1609.34 km, however at the design velocity of 104.6 kph, the drag is 196 N; which requires more battery capacity than the 100 kWh maximum of the baseline model. With a fixed frontal area, drag reduction can come from lowered velocity or reduced CD. CD reduction is attempted in four ways: side skirts between the fenders, a raised ride height, an elongated diffuser, and a widened rear. Side skirts were added to move pressure recovery from the front ducts to the diffuser by lowering the pressure between the side skirts; this had the intended effect but increased the tendency of the flow to separation in the already-separated areas. There was no significant change in pressure drag, but the shear drag and downforce increased. The ride height was increased to reduce drag and downforce; this change did not have a significant effect on the resultant forces and the separation on the underbody was largely unchanged. The diffuser was extended by 12.7 cm without modifying the aspect ratio, to lower the divergence angle. The pressure and shear drag reduced by 8 N and 1.1 N, respectively, and downforce decreased by 80 N, but separation in the diffuser was not eliminated. Finally, the fourth strategy reduced the divergence angle to approximately zero degrees by widening the center of the vehicle. This decreased pressure drag by 13 N and downforce by 188 N. Additionally, this strategy allows a larger 180 kWh battery, which permits 1609.34 km of range at 104.6 kph.

In this thesis, a method was developed to evaluate the impact of bidirectional electric vehicle (EV) charging on power system reliability using Synergi Electric software. Load profiles, EV availability, EV state-of-charge (SOC) were important factors considered in this study. The analysis in this study is based on local and interregional vehicle-to-grid (V2G) implementation at different load points in the system. In general, local V2G implementation is observed to be more effective in improving system reliability over interregional V2G power flow. System Average Interruption Duration Index (SAIDI) and System Average Interruption Frequency Index (SAIFI) improvements were observed to increase with increasing SOC but are less progressive between higher SOCs. Based on the simulation results, the method proves to be sufficient in calculating SAIDI and SAIFI reliability indices as the simulation results are corroborated with theory.

Global energy consumption continues to grow, driving the need for cheap, power-dense power electronics. Replacing the incumbent silicon insulated gate bipolar transistors with silicon carbide (SiC) metal oxide semiconductor field effect transistors (MOSFETs) has been proposed as a solution to increase the power densities of power converters in some applications. One such application is electric vehicles (EVs) where the efficiency and weight of the power electronics are critical; however, modern packaging technologies are still limiting the performance of SiC MOSFETs. One promising trend in power semiconductor packaging technologies is the use of printed circuit boards (PCBs) because the technology is mature—resulting in low costs—and the allowable stackups are ideal for integrating driving circuitry and power loop components—resulting in reduced manufacturing complexity. This thesis presents the design and analysis of two PCB-embedded 1.2 kV SiC MOSFET half-bridge packages and a hybrid PCB/DBC-based 1.2 kV SiC MOSFET full-bridge package for EV on-board charger applications. The first of the two PCB-embedded packages has integrated gate drive circuitry, less than 2.3 nH loop inductances, and dual-sided cooling with a total junction-to-case thermal resistance (RTH,JC) of 0.12 K/W. The second PCB-embedded package has only drain-side cooling to allow for surface mount terminals, has an area of 37.1 mm x 18.5 mm due to the removal of the gate drive circuitry, and has less than 2.4 nH loop inductances. The PCB/DBC-based full-bridge package has an RTH,JC of 0.65 K/W, less than 4.5 nH, and integrated gate drive circuitry. / M.S. / The continued increase in global energy consumption has led to concerns about sustainability, and as renewable energy generation is adopted more broadly, more efficient means of converting electrical energy from one form to another are required. Some applications, such as electric vehicles (EVs), also require a lightweight and a low volume from their converters in addition to high efficiency. The packaging of the semiconductors used in converters is important to the overall electrical efficiency of the converter and can also have an impact on the size of the converter as well. This thesis explores the design and analysis of three package structures for the semiconductors used in the on-board charger of an EV. These package structures are unified under the common theme of using printed circuit boards (PCBs) in the package itself. PCBs are commonly used to route the electrical connections between packaged semiconductors and other components in the converter, but they are not usually integrated into the package itself. The hope is that by integrating the PCB into the semiconductor package, higher-efficiency, lighter-weight, and smaller-volume converters will be possible.