Bidirectional vehicle-to-grid (V2G) system utilizes the batteries of parked electric-drive-vehicles to provide energy storage and backup services in a power system. Such services in a V2G-equipped microgrid system can be used as an enabler of enhancing the renewable energy source (RES) penetration by storing the energy during the surplus of RES supply and supplying the energy during the lack of RES supply. In this research, we aim at enhancing the storage capacity of V2G system by introducing a novel vehicle-to-vehicle power transfer operation that runs on the top of V2G services. The vehicle-to-vehicle (V2V) operation transfers the energy from the source vehicles (which are parked for relatively longer times) to the destination vehicles (which are parked for relatively shorter times). The depleted energy of the source vehicles is fulfilled by the surplus RES supply in the future. In this way, the destination vehicles are effectively charged by RES supply, thereby enhancing the storage capacity of the V2G system. We can also say that the V2V operation would become beneficial only when there is a sufficient amount of surplus RES supply in the future. We propose a decision rule to distinguish if a vehicle should be a source vehicle or a destination vehicle during the V2V operation. The decision rule is designed based on the two factors, namely the state-of-charge of vehicle’s battery, and the remaining time of vehicle to depart. In this research, we conduct a comprehensive study to analyze the impacts of state-of-charge and mobility pattern of vehicles on different performance metrics via simulation. The results shows that in order to achieve better performance of V2V operation, the state-of-charge of vehicle’s battery should be given more priority over the remaining time of vehicle to depart. The vehicle mobility pattern with unexpected departure greatly reduced the overall performance of the V2G system.

This paper explores how the concept of Vehicle to Grid (V2G) could bring benefits to California's electric grid, transportation sector, and environmental goals.

The transition to a zero emissions society has already begun. A big effort should be done in the energy area and as engineers we have the power and the responsibility of using all our knowledge to look for the best and optimal solutions to achieve it.   The aim of this project is to study the new technologies that are appearing in the field of electric cars vehicles as well as try to develop a way of integrating this into a project of a real long-term parking. The study will be focused on the use of the technologies known as V2X. This technology has been designed for a bidirectional flow of energy between the EV and the charging points in where the vehicles are connected. This opens new doors to the V2G (Vehicle to grid) and to the V2H (Vehicle to home), giving the opportunity not only to charge the vehicles but also use the energy stored in these vehicles for the situations needed, such as improve the grid stability, the use of microgrids and the money saving for the vehicle’s owners. The study was conducted in AirSon a company found in Ängelholm, Sweden. For the study, several parts were developed. First data acquisition for detailed knowledge of the electrical consumes of the company was done. Then a simulation of production of a photovoltaic installation was done in order to integrate this system into the company and help to feed the charge of the long-term parking with renewable energies. In third place a discussion of how the parking could be developed was held as well as the study of the viability of this.  In the results some interesting data has been obtained. In first place from the analysis of the consumes of AirSon the figures representing the electricity usage of each building have been obtained. In second place the calculous of three different photovoltaic installations in different areas is made, obtaining the production per month and hour in each area. Obtaining a total production during June of 37.1 MWh being the month with most production and 2.6 MWh in December being this the month with least production rate. Finally in the results the estimation of the SoC (State of charge) of the cars that arrive to AirSon is found, obtaining an average of 5.37 kWh less energy than the total capacity of the battery at the arrival moment, this means that for completely charge the car the installation needs to provide this 5.37 kWh to each car. Once the energy is delivered into the cars, the parking will be able to take back electricity from the cars in case of necessity of the grid. However, the system will never take more energy from the cars than the one delivered for charging them, due to the parking statement of ensure at least the same energy to the vehicles than the one at the arrival moment. After analysing the results, the key issues are found, such as the weather dependence, the early stage of the technologies and the battery degradation as well as the big investment that needs to be done for having enough energy for the parking to work. Concluding this work with the idea that there is a big potential for the job to work but there are big barriers that need to be overcome first.

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.

Avec l'importance que prend le parc de véhicules électriques rechargeable (VER) depuis ces dix dernières années et au vu de l'important taux de croissance le caractérisant, se pose alors la question de l'infrastructure de recharge y inhérente. Une manière d'en tirer bénéfice et d'en minimiser l'impact consistera en l'agrégation en flotte et de gérer cette dernière en conséquence. L'objectif général de la thèse est de proposer et de développer des algorithmes décentralisés qui permettront de minimiser les impacts les plus critiques attendus d'une forte pénétration de VERs. La prise en compte de la réversibilité des chargeurs actuels et de leur fonctionnement sur les quatre quadrants, les algorithmes proposés, rendent également possible la fourniture de services système au réseau ; cependant il faut aussi tenir compte du caractère aléatoire de plusieurs variables telles que les heures d'arrivée te de départ des véhicules considérés, de l'état de charge initial entre autres. Cette thèse introduit d'abord une approche globale et une optimisation locale afin d'établir un benchmark solide à des fins d'évaluation des techniques développées dans ce travail. Vient ensuite ce qui est la contribution majeure représentée par deux méthodologies d'optimisation lesquelles sont basées sur la théorie des jeux évolutionniste. Toutes les deux techniques introduisent la notion d'équité dans la répartition des tâches et des ressources entre VERs et donnent plus de poids aux contraintes liées au rôle de l'usager/propriétaire du véhicule et de son implication dans la gestion de la demande. En outre, l'une de ces méthodes comprend des solutions de rechange pour intégrer la charge rapide dans le processus de planification, tandis que l'autre méthode permet au VER de fournir des services auxiliaires comme le remplissage des creux de demande, l'effacement de la pointe le pic de rasage, active, d'équilibrer la puissance active ou encore de fournir de l'énergie réactive. / With a stock of Plug-in electric vehicles (PEVs) under continuous grow during the last ten years, concerns have been raised in terms of their charging infrastructure and their integration into the electricity distribution systems. If PEVs are considered as a fleet, both their impact and benefit for the electrical power system can be substantial. The general objective of this thesis is to propose and develop decentralized algorithms allowing to mitigate the most critical impacts expected to occur with the integration of PEVs. Taking into account the reversibility of chargers, the proposed algorithms are intended to consider re-injection of energy, in order to provide ancillary services to the grid. Moreover, algorithms are supposed to consider the stochastic nature of variables like the arrival and departure of PEVs, their initial state of charge, among others. Under these premises and taking into account earlier contributions, this thesis introduces a centralized approach and a distributed optimization approach in order to have a solid benchmark for the justification of the most elaborate contributions of the last part of this work. After these first experiences, the most important contribution of this thesis is represented in two decentralized optimization methodologies that were developed in details based on concepts of evolutionary game theory. Both of them introduce the concept of fairness in the allocation of tasks and resources among PEVs, and give more weight to social constraints represented on the role of PEV owners in the load managing process. Furthermore, one of these methodologies includes alternatives to integrate fast charging rates in the scheduling process, while the other methodology allows PEVs to provide ancillary services like valley filling, peak shaving, active and reactive power balancing, and reactive power supply.

No description available.

Les engagements étatiques relatifs au secteur du transport promouvoient la popularisation des véhicules rechargeables conformément aux exigences actuelles qu'elles soient environnementales, techniques ou encore économiques. Ipso facto, ces travaux de thèse, assimilés à la thématique des Smart Grids, exposent une contribution à une gestion orientée du tryptique réseaux électriques, véhicules rechargeables et secteurs résidentiels. La première étape du travail consiste en l'évaluation des impacts liés à un taux de pénétration élevé. Les travaux se sont ensuite focalisés sur deux problèmes importants qui sont la tenue du plan de tension et le vieillissement accéléré des transformateurs de distribution HTA/BT, plus particulièrement ceux alimentant des secteurs résidentiels. Partant, des stratégies de modulation de la charge des batteries embarquées sont proposées et évaluées. Dans une seconde partie, en se basant sur l'hypothèse de bidirectionnalité énergétique du véhicule électrique hybride rechargeable (Plug-in Hybrid Electric Vehicle - PHEV), est exploré les possibilités d'effacement de pointe et de diminution des puissances souscrites ; conformément au concept Vehicle-to-Home. Les aspects économiques ne sont pas évacués ; à ce titre la minimisation de la facture énergétique d'un logement fait l'objet d'un regard particulier sous contrainte d'une tarification variable, le V2H servant de levier. Le véhicule bidirectionnel est enfin mis à contribution via une algorithmique adaptée à des fins de réglage du plan de tension et contribue ainsi au concept Vehicle-to-Grid.

Depletion of fossil fuel reserves, increasing awareness of air pollution levels and continuous rise in gasoline prices are some of the major drives that have been revolutionizing the automotive industry since the last decade. These factors combined are causing conventional automobiles with internal combustion engines (ICE) to be replaced with plugin vehicles. The on-board rechargeable battery packs in plugin vehicles can be recharged by connecting to the utility grid using a plug. The energy stored in the on-board battery packs has attractive benefits for grid support, and this promotes the idea of Vehicle-to-Grid (V2G). V2G power transactions allow energy from the on-board battery packs to be sent back to the utility grid for support in peak shaving and provide reactive power compensation. One natural consequence that arises with the introduction of V2G is a sharp increase in the need for high-performance power electronic interface between the utility grid and the battery pack. Therefore, research on bidirectional battery chargers for plugin vehicles is imperative in order to aid in the promotion of V2G. This thesis focuses on the design and development in a two-stage level-two on-board bidirectional battery charger.

Depletion of fossil fuel reserves, increasing awareness of air pollution levels and continuous rise in gasoline prices are some of the major drives that have been revolutionizing the automotive industry since the last decade. These factors combined are causing conventional automobiles with internal combustion engines (ICE) to be replaced with plugin vehicles. The on-board rechargeable battery packs in plugin vehicles can be recharged by connecting to the utility grid using a plug. The energy stored in the on-board battery packs has attractive benefits for grid support, and this promotes the idea of Vehicle-to-Grid (V2G). V2G power transactions allow energy from the on-board battery packs to be sent back to the utility grid for support in peak shaving and provide reactive power compensation. One natural consequence that arises with the introduction of V2G is a sharp increase in the need for high-performance power electronic interface between the utility grid and the battery pack. Therefore, research on bidirectional battery chargers for plugin vehicles is imperative in order to aid in the promotion of V2G. This thesis focuses on the design and development in a two-stage level-two on-board bidirectional battery charger.

In 2015, the Paris Agreement was signed by almost 200 countries in order to define targets for future work within sustainability and to reduce further climate impact. Since then, the European Union has taken these targets in earnest and implemented purposeful legislation for all of its members. The Swedish government has introduced an even more ambitious climate policy framework in order to achieve as low national pollution levels as possible. By doing so, regional and local authorities have been forced to take action in order to meet the defined targets for 2030 and 2050. This implies that the Swedish transport sector is now facing a major challenge - to reduce its emissions of greenhouse gases by at least 70 % as of the level of 2010. A common opinion is that electric vehicles may play an important role in this task. To establish electric drivelines within the transport sector has been a worldwide vision for decades and it seems to be one of the most promising options today. Sweco has together with AB Volvo, Volvo Cars AB, Göteborg Energi, ABB Ltd and Vattenfall AB financed the official project PussEL. Mainly, the purpose of this project was to estimate the potential of a full electrification of the transport sector in a medium size city by 2030. For this project, it was of particular interest to use Gothenburg, Sweden, as a case study. It has been most relevant to consider the electrification of road transport, including both private and public transport as well as goods distribution. The analysis has resulted in a message to residents, businesses and politicians, that an extensive electrification is doable. However, the results also indicate that the distribution grid will require a significant extension. It will definitely require serious effort and will rely on the implementation of smart and controllable vehicle charging. Nevertheless, this might be just what it takes to become one of the world leading countries in sustainable transports. Secondly, the purpose of this thesis is also to clarify the potential of the local parking company to act as an aggregator for charging and discharging of electric vehicles. By considering local driving patterns, parking profiles in car parks, as well as prerequisites of the electricity markets, it has been possible to identify the technical potential. It has been of interest to investigate services including both smart charging (V1G) and vehicle-to-grid (V2G), in order to support an extensive electrification. The estimation has been done using available software from MathWorks: MATLAB. Previous research states that battery degradation from V2G services varies according to the depth of discharge (DOD). Thus, it is desired to utilize services that require a small DOD in order to minimize the reduction of battery lifetime. Considering the economic potential, this thesis examines several available services as an aggregator. Due to the variable capacity in each car parkin combination with the requirements set by the electricity markets, some services have been excluded at an early stage of the analysis. Although, besides economic profitability, a key to success is to keep the concept user-friendly. It must be kept in mind that car owners most likely will prioritize the freedom of mobility rather than leasing their vehicles as mobile batteries. As the Swedish lawyer Thomas Thorild once said: To think freely is great, but to think rightly is greater.