Dissertations / Theses: 'Energy Storage, Smart Grid'

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Damnjanovic, Nenad. "Smart Grid Functionality of a PV-Energy Storage System." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3058.

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Renewable Energy will be the key to preserving the Earth's remaining resources and continuing this surge of technological progress that we have experienced this past century. New philosophies of how/when/where energy should be consumed and produced are attempting to improve upon the current grid infrastructure. The massive advancement in communications, renewable and control systems will allow this new-age electric grid to maximize its efficiency while reducing cost. Renewable, "green" energy is now at the forefront of innovation. As the world population increases, there will be a need to free ourselves from natural resources as much as possible. Advanced Energy Storage Systems (AESS) will play a vital and large role in this new-age infrastructure. Because renewable energy is not constant (aside from hydroelectricity), this energy needs to be conserved and used at appropriate times. The Sustainable Electric Energy Delivery System (SEEDS) project features an AESS made from Lithium-ion phosphate (LiFeP04) and a Photovoltaic (PV) source connected to the grid. Every current technology has different parameters, efficiency, charge/discharge rates, lifespan, etc. The current Li-FeP04 system will be used as an example and a model. This project acts as a pilot project for future large scale smart grid endeavors. This thesis is written in conjunction with the SEEDS project and will outline and discuss in detail the findings. For the PV system, the performance is analyzed. For the storage system, the round-trip efficiency (measured) and life cycle are broken down. The thesis concludes with a capacity sizing estimation of the storage system which is based on the renewable energy source (solar).

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Wang, Lu. "Optimization and control of energy storage in a smart grid." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/412630/.

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Environmental issues such as global warming, limited storage of fossil fuels and concerns about cost and energy efficiency are driving the development of the future smart grid. To reduce carbon emissions, it is expected that there will be a large-scale increase in the penetration of renewable generators (RGs), electric vehicles (EVs) and electrical heating systems. This will require new control approaches to ensure the balance of generation and consumption and the stability of the power grid. Energy storage can be used to support grid operations by controlling frequency and voltage, and alleviating thermal overload. This thesis makes three novel contributions to the field: optimal battery sizing; optimal dispatch of vehicle-to-grid batteries; and optimal coordination of EV batteries and RGs. Appropriate sizing of the energy storage is very important when using it to support the power system. In this thesis, an approach has been proposed to determine the capacity of a battery storage providing support during N-1 contingencies to relieve transmission line thermal overload. In addition, as the increasing use of EV is an inevitable trend in the future smart grid, the system's peak demand may increase significantly due to EV charging, causing serious overloading of some power system facilities such as transformers and cables in the grid if an effective EV battery dispatch strategy is not used. Therefore, this report presents a dispatch strategy for EV batteries based on the Analytic Hierarchy Process taking into account both vehicle users' and power system requirements and priorities, as well as the constraints of the battery system. However, using renewable power to charge EVs is the prerequisite of realizing clean transport. EVs can store the extra renewable power and feed it into the grid when needed via vehicle-to-grid operations to increase the utilization and integration of RGs in the power grid. Thus, the optimal dispatch of EVs and RGs to realize the synergy between them will be one of the key challenges. Two optimal agent-based coordinated dispatch strategies are developed in this thesis, respectively using dynamic programming and the A* search procedure (comparisons between these two algorithms are made and discussed), for the synergistic integration of EVs and RGs, so that the benefits of both EV users and power grid are maximized. Each of the proposed approaches was tested on an IEEE Reliability Test System or a modified UK generic distribution system (UKGDS) using MATLAB. The simulation results demonstrate the feasibility and efficacy of the proposed approaches.

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Östergård, Rickard. "Flywheel energy storage : a conceptucal study." Thesis, Uppsala universitet, Elektricitetslära, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-164500.

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This master thesis was provided by ABB Cooperate Research in Västerås. This study has two major purposes: (1) to identify the characteristics of a flywheel energy storage system (FESS), (2) take the first steps in the development of a simulation model of a FESS. For the first part of this master thesis a literature reviews was conducted with focus on energy storage technologies in general and FESS in particular. The model was developed in the simulation environment PSCAD/EMTDC; with the main purpose to provide working model for future studies of the electrical dynamics of a flywheel energy storage system. The main conclusion of the literature review was that FESS is a promising energy storage solution; up to multiple megawatt scale. However, few large scale installations have so far been built and it is not a mature technology. Therefore further research and development is needed in multiple areas, including high strength composite materials, magnetic bearings and electrical machines. The model was implemented with the necessary control system and tested in a simulation case showing the operational characteristics.

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Barakat, Mahmoud. "Development of models for inegrating renewables and energy storage components in smart grid applications." Thesis, Normandie, 2018. http://www.theses.fr/2018NORMC217/document.

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Cette thèse présente un modèle unique du MASG (Modèle d’Architecture du Smart Grid) en considérant l 'état de l’art des différentes directives de recherche du smart grid. Le système hybride de génération d'énergie active marine-hydrogène a été modélisé pour représenter la couche de composants du MASG. Le système intègre l'électrolyseur à membrane d’échange de proton (à l’échelle de méga watt) et les systèmes de piles à combustible en tant que composants principaux du bilan énergétique. La batterie LiFePO4 est utilisée pour couvrir la dynamique rapide de l'énergie électrique. En outre, la thèse analyse le système de gestion de l'énergie centralisé et décentralisé. Le système multi-agents représente le paradigme du système décentralisé. La plate-forme JADE est utilisée pour développer le système multi-agents, en raison de son domaine d'application général, de ses logiciels à licence libre, de son interface avec MATLAB et de sa calculabilité avec les standards de la Fondation des Agents Physiques Intelligentes. Le système de gestion d'énergie basé sur JADE équilibre l'énergie entre la génération (système de conversion d'énergie marine-courant) et la demande (profil de charge résidentielle) pendant les modes de fonctionnement autonome et connecté au réseau. Le modèle proposé du MASG peut être considéré comme une étude de cas pilote qui permet l'analyse détaillée et les applications des différentes directions de recherche du smart grid
This thesis presents a unique model of the SGAM (Smart Grid Architecture Model) with considering the state of the art of the different research directions of the smart grid and. The hybrid marine-hydrogen active power generation system has been modeled to represent the component layer of the SGAM. The system integrates the MW scale PEM electrolyzer and fuel cell systems as the main energy balance components. The LiFePO4 battery is used to cover the fast dynamics of the electrical energy. Moreover, the thesis analyzes the centralized and the decentralized energy management system. The MAS (Multi-Agent Systems) represents the paradigm of the decentralized system. The JADE platform is used to develop the MAS due to its general domain of application, open source and free license software, interface with MATLAB and the computability with the FIPA (Foundation of Intelligent Physical Agent) standards. The JADE based energy management system balances the energy between the generation (marine-current energy conversion system) and the demand side (residential load profile) during the stand-alone and the grid-connected modes of operation. The proposed model of the SGAM can be considered as a pilot case study that enables the detailed analysis and the applications of the different smart grid research directions

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Busuladzic, Ishak, and Marcus Tjäder. "Performance Indicators for Smart Grids : An analysis of indicators that measure and evaluate smart grids." Thesis, Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-48902.

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Sweden has developed ambitious goals regarding energy and climate politics. One major goal is to change the entire electricity production from fossil fuels to sustainable energy sources, this will contribute to Sweden being one of the first countries in the world with non-fossil fuel in the electricity sector. To manage this, major changes need to be implemented and difficulties on the existing grid will occur with the expansion of digitalization, electrification and urbanization. By using smart grids, it is possible to deal with these problems and change the existing electricity grid to use more distributed power generation, contributing to flexibility, stability and controllability. The goal with smart grids is to have a sustainable electricity grid with low losses, security of supply, environmental-friendly generation and also have choices and affordable electricity for customers. The purpose of this project is to identify and evaluate several indicators for a smart grid, how they relate and are affected when different scenarios with different technologies are implemented in a test system. Smart grid indicators are quantified metrics that measure the smartness of an electrical grid. There are five scenarios where all are based on possible changes in the society and electricity consumption, these scenarios are; Scenario A – Solar power integration, Scenario B – Energy storage integration, Scenario C – Electric vehicles integration, Scenario D – Demand response and Scenario E – Solar power, Energy storage, Electric vehicles and Demand response integration. A model is implemented in MATLAB and with Monte Carlo simulations expected values, standard deviation and confidence interval were gained. Four selected indicators (Efficiency, capacity factor, load factor and relative utilization) was then analyzed. The results show that progress on indicators related to all smart grid characteristics is needed for the successful development of a smart grid. In scenario C, all four selected indicators improved. This shows that these indicators could be useful for promoting the integration of electric vehicles in an electricity grid. In Scenario A, solar power integration contributed to all indicators deteriorate, this means that, technical solutions that can stabilize the grid are necessary to implement when integrating photovoltaic systems. The load factor is a good indicator for evaluating smart grids. This indicator can incentivize for an even load and minimize the peak loads which contributes to a flexible and efficient grid. With the capacity factor, the utilization and free capacity can be measured in the grid, but it can counteract renewable energy integration if the indicator is used in regulation.

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Khasawneh, Hussam Jihad. "Sizing Methodology and Life Improvement of Energy Storage Systems in Microgrids." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429638668.

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Pantaleo, Gaetano. "Energy management di un sistema energetico ibrido on-grid." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.

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Il livello di emissioni di inquinanti e gas serra negli ultimi decenni è salito vertiginosamente anche a causa della produzione di energia elettrica, nonostante la sempre crescente quota riguardante le rinnovabili, le fonti fossili e nucleari sono ancora le più utilizzate. Nell’ambito della gestione della risorsa elettrica è sempre più frequente l’utilizzo di sistemi ibridi off-grid ed on-grid come nel nostro caso. I sistemi HES e RES che possono essere combinati utilizzando fonti rinnovabili come solare ed eolico o geotermico o integrati a piccoli generatori nel caso di sistemi stand-alone. Nell’elaborato si valuta con l’implementazione in un software di calcolo di strategie di energy management la fattibilità economica, attraverso l’LCOE (Levelized cost of energy), di un impianto composto da pannelli fotovoltaici e sistema di accumulo installato presso la sede di Ingegneria dell’Università di Bologna di Via Terracini e la sede del Politecnico di Bari in Via Edoardo Orabona. L’analisi ha l’obiettivo di valutare la fattibilità economica dell’impianto e valutare quanto incidono le condizioni climatiche al contorno sul calcolo dell’LCOE. Il calcolo dell’LCOE verrà confrontato con i valori attuali del prezzo dell’energia elettrica e verranno valutate le differenze.

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Halawani, Mohanad. "An iterative analytical design framework for the optimal designing of an off-grid renewable energy based hybrid smart micro-grid : a case study in a remote area - Jordan." Thesis, Abertay University, 2015. https://rke.abertay.ac.uk/en/studentTheses/40b75bc8-d237-4aaf-9668-797739f49f74.

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Creative ways of utilising renewable energy sources in electricity generation especially in remote areas and particularly in countries depending on imported energy, while increasing energy security and reducing cost of such isolated off-grid systems, is becoming an urgently needed necessity for the effective strategic planning of Energy Systems. The aim of this research project was to design and implement a new decision support framework for the optimal design of hybrid micro grids considering different types of different technologies, where the design objective is to minimize the total cost of the hybrid micro grid while at the same time satisfying the required electric demand. Results of a comprehensive literature review, of existing analytical, decision support tools and literature on HPS, has identified the gaps and the necessary conceptual parts of an analytical decision support framework. As a result this research proposes and reports an Iterative Analytical Design Framework (IADF) and its implementation for the optimal design of an Off-grid renewable energy based hybrid smart micro-grid (OGREH-SμG) with intra and inter-grid (μG2μG & μG2G) synchronization capabilities and a novel storage technique. The modelling design and simulations were based on simulations conducted using HOMER Energy and MatLab/SIMULINK, Energy Planning and Design software platforms. The design, experimental proof of concept, verification and simulation of a new storage concept incorporating Hydrogen Peroxide (H2O2) fuel cell is also reported. The implementation of the smart components consisting Raspberry Pi that is devised and programmed for the semi-smart energy management framework (a novel control strategy, including synchronization capabilities) of the OGREH-SμG are also detailed and reported. The hybrid μG was designed and implemented as a case study for the Bayir/Jordan area. This research has provided an alternative decision support tool to solve Renewable Energy Integration for the optimal number, type and size of components to configure the hybrid μG. In addition this research has formulated and reported a linear cost function to mathematically verify computer based simulations and fine tune the solutions in the iterative framework and concluded that such solutions converge to a correct optimal approximation when considering the properties of the problem. As a result of this investigation it has been demonstrated that, the implemented and reported OGREH-SμG design incorporates wind and sun powered generation complemented with batteries, two fuel cell units and a diesel generator is a unique approach to Utilizing indigenous renewable energy with a capability of being able to synchronize with other μ-grids is the most effective and optimal way of electrifying developing countries with fewer resources in a sustainable way, with minimum impact on the environment while also achieving reductions in GHG. The dissertation concludes with suggested extensions to this work in the future.

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Yang, You. "Privacy-enhancing and Cost-efficient Energy Management for an End-User Smart Grid in the Presence of an Energy Storage." Thesis, KTH, Teknisk informationsvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214410.

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A smart grid is an energy network which manages the energy generation anddistribution more efficiently following the real-time energy demands of end-usersthrough control and communication technologies. Deploying smart grids canimprove the energy efficiency, enhance the network reliability, and reduce costsof both the energy provider and end-users. However, these benefits come withprivacy challenges. One of such challenges is the smart meter privacy problem.In a smart grid, the smart meter is used to record the real-time energy supplyand to feedback the records to the energy provider. Since the energy is suppliedon the demand, these smart meter records contain the information of energydemand profile of the end-user and therefore it brings the risk of compromisingconsumers’ privacy. Regarding this issue, a rechargeable energy storage canbe used to mitigate this risk by manipulating consumers’ energy consumptionprofile. However, privacy enhancement will lead to increasing the consumers’cost for purchasing energy, which violates the original cost-saving motivation forconsumers. In this work, we investigate the design of a privacy-enhancing andcost-efficient energy management strategy. In detail, dynamic pricing of energyis assumed so that the consumer has the opportunity to utilize the energy storageto reduce the energy cost. Furthermore, the Kullback-Leibler divergence rate isused as privacy measure, and the expected cost-saving rate is also evaluated. Tostudy the trade-off between privacy and cost, the proposed objective functionis a weighted sum of Kullback-Leibler divergence rate and expected cost-savingrate. We first decompose both Kullback-Leibler divergence rate and expectedcost-saving rate in additive forms over a finite horizon. Based on the predefinedbelief states, we express the overall objective function by state-actionpairs and reformulate the energy management design into an Markov decisionprocess (MDP), and the finite horizon optimal solution can be obtained by usingBellman dynamic programming. Finally, in the special case of independent andidentically distributed (i.i.d) demand, we explicitly characterize a stationarypolicy for the infinite horizon average cost by showing this policy can preserve acertain invariance property of the belief state. And we also show this stationarypolicy can achieve an optimal privacy leakage rate.
Ett smart nät är ett energinätverk som hanterar energigenerering och distributionmer effektivt efter slutanvändarnas energikrav i realtid genom kontrolloch kommunikationsteknik. Genom att distribuera smarta nät kan du förbättraenergieffektiviteten, förbättra nätverk säkerheten och minska kostnadernaför både energileverantören och slutanvändarna. Men dessa fördelar kommermed privata utmaningar. En av dessa utmaningar är problemet med smartamätare. I ett smart nät används den smarta mätaren för att registrera energitillförselni realtid och att återkoppla mätningarna till energileverantören.Eftersom energinlevereras efter begäran, innehåller dessa smarta mätarregisterinformationen om slutanvändarens energibehovs profil och därmed riskerardet att äventyra konsumenternas privatliv. När det gäller denna fråga kanen uppladdningsbar energilagring användas för att minska denna risk genomatt förändra konsumenternas energiförbruknings profil. Förbättringen av privatkommerdock att leda till att konsumenternas kostnad för inköp av energiökar, vilket strider mot den ursprungliga kostnads besparande motivationen förkonsumenterna. I detta arbete undersöker vi utformningen av en privatliv höjandeoch kostnads effektiv energihanterings strategi. I detalj antas dynamiskprissättning av energi så att konsumenten har möjlighet att utnyttja energilagringför att minska sin energikostnad. Vidare används Kullback-Leiblerdivergensvärde som privatliv metrisk, och den förväntade kostnads besparingsvärde utvärderas också. För att studera avvägningen mellan privatliv och kostnadär den föreslagna objektiv funktionen en viktad summa av Kullback-Leiblerdivergensvärde och förvÃďntad kostnads besparings värde. Vi bryter först itubåde Kullback-Leibler-divergens värde och den förväntade kostnads besparingeni additativa former över en finit horisont. Baserat på de fördefinierade antagandenauttrycker vi den övergripande objektiva funktionen med state-action-paroch omformulerar energistyrnings designen i en Markov-beslutsprocess (MDP),och den finita optimala lösningen kan erhållas genom att använda dynamiskBellman-programmering. Slutligen, i det speciella fallet med oberoende ochidentiskt distribuerad (i.i.d) efterfrågan karakteriserar vi uttryckligen en stationärpolitik för den oändliga horisontens genomsnittliga kostnad genom attvisa att denna policy kan bevara en viss invariant egenskap hos trosuppfattningen.Vi visar också att man med den här stationära principen kan uppnå ettoptimalt privatliv läckagevärde.

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Keerthisinghe, Chanaka. "Fast Solution Techniques for Energy Management in Smart Homes." Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/16033.

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In the future, residential energy users will seize the full potential of demand response schemes by using an automated smart home energy management system (SHEMS) to schedule their distributed energy resources. The underlying optimisation problem facing a SHEMS is a sequential decision making problem under uncertainty because the states of the devices depend on the past state. There are two major challenges to optimisation in this domain; namely, handling uncertainty, and planning over suitably long decision horizons. In more detail, in order to generate high quality schedules, a SHEMS should consider the stochastic nature of the photovoltaic (PV) generation and energy consumption. In addition, the SHEMS should accommodate predictable inter-daily variations over several days. Ideally, the SHEMS should also be able to integrate into an existing smart meter or a similar device with low computational power. However, extending the decision horizon of existing solution techniques for sequential stochastic decision making problems is computationally difficult and moreover, these approaches are only computationally feasible with a limited number of storage devices and a daily decision horizon. Given this, the research investigates, proposes and develops fast solution techniques for implementing efficient SHEMSs. Specifically, three novel methods for overcoming these challenges: a two-stage lookahead stochastic optimisation framework; an approximate dynamic programming (ADP) approach with temporal difference learning; and a policy function approximation (PFA) algorithm using extreme learning machines (ELM) are presented. Throughout the thesis, the performance of these solution techniques are benchmarked against dynamic programming (DP) and stochastic mixed-integer linear programming (MILP) using a range of residential PV-storage (thermal and battery) systems. We use empirical data collected during the Smart Grid Smart City project in New South Wales, Australia, to estimate the parameters of a Markov chain model of PV output and electrical demand using an hierarchical approach, which first cluster empirical data and then learns probability density functions using kernel regression (Chapter 2). The two-stage lookahead method uses deterministic MILP to solve a longer decision horizon, while its end-of-day battery state of charge is used as a constraint for a daily DP approach (Chapter 4). Here DP is used for the daily horizon as it is shown to provide close-to-optimal solutions when the state, decision and outcome spaces are finely discretised (Chapter 3). However, DP is computationally difficult because of the dimensionalities of state, decision and outcome spaces, so we resort to MILP to solve the longer decision horizon. The two-stage lookahead results in significant financial benefits compared to daily DP and stochastic MILP approaches (8.54% electricity cost savings for a very suitable house), however, the benefits decreases as the actual PV output and demand deviates from their forecast values. Building on this, ADP is proposed in Chapter 5 to implement a computationally efficient SHEMS. Here we obtain policies from value function approximations (VFAs) by stepping forward in time, compared to the value functions obtained by backward induction in DP. Similar to DP, we can use VFAs generated during the offline planning phase to generate fast real-time solutions using the Bellman optimality condition, which is computationally efficient compared to having to solve the entire stochastic MILP problem. The decisions obtained from VFAs at a given time-step are optimal regardless of what happened in the previous time-steps. Our results show that ADP computes a solution much faster than both DP and stochastic MILP, and provides only a slight reduction in quality compared to the optimal DP solution. In addition, incorporating a thermal energy storage unit using the proposed ADP-based SHEMS reduces the daily electricity cost by up to 57.27% for a most suitable home, with low computational burden. Moreover, ADP with a two-day decision horizon reduces the average yearly electricity cost by a 4.6% over a daily DP method, yet requires less than half of the computational effort. However, ADP still takes a considerable amount of time to generate VFAs in the off-line planning phase and require us to estimate PV and demand models. Given this, a PFA algorithm that uses ELM is proposed in Chapter 6 to overcome these difficulties. Here ELM is used to learn models that map input states and output decisions within seconds, without solving an optimisation problem. This off-line planning process requires a training data set, which has to be generated by solving the deterministic SHEMS problem over couple of years. Here we can use a powerful cloud or home computer as it is only needed once. PFA models can be used to make fast real-time decisions and can easily be embedded in an existing smart meter or a similar low power device. Moreover, we can use PFA models over a long period of time without updating the model and still obtain similar quality solutions. Collectively, ADP and PFA using ELM can overcome challenges of considering the stochastic variables, extending the decision horizon and integrating multiple controllable devices using existing smart meters or a device with low computational power, and represent a significant advancement to the state of the art in this domain.

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Alhaider, Mohemmed Masooud. "Optimal Demand Response Models with Energy Storage Systems in Smart Grids." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6451.

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This research aims to develop solutions to relieve system stress conditions in electric grids. The approach adopted in this research is based on a new concept in the Smart Grid, namely, demand response optimization. A number of demand response programs with energy storage systems are designed to enable a community to achieve optimal demand side energy management. The proposed models aim to improve the utilization of the demand side energy through load management programs including peak shaving, load shifting, and valley lling. First, a model is proposed to nd the optimal capacity of the battery energy storage system (BESS) to be installed in a power system. This model also aims to design optimal switchable loads programs for a community. The penetration of the switchable loads versus the size of the BESS is investigated. Another model is developed to design an optimal load operation scheduling of a residential heating ventilation and air-conditioning system (HVACs). This model investigates the ability of HVACs to provide optimal demand response. The model also proposes a comfort/cost trade-os formulation for end users. A third model is proposed to incorporate the uncertainty of the photovoltaic power in a residential model. The model would nd the optimal utilization of the PV-output to supply the residential loads. In the first part of this research, mixed integer programming (MIP) formulations are proposed to obtain the optimal capacity of the (BESS) in a power system. Two optimization problems are investigated: (i) When the BESS is owned by a utility, the operation cost of generators and cost of battery will be minimized. Generator on/o states, dispatch level and battery power dispatch level will be determined for a 24-hour period. (ii) When the BESS is owned by a community for peak shaving, the objective function will have a penalty component for the deviation of the importing power from the scheduled power. MIP problems are formulated and solved by CPLEX.The simulation results present the effect of switchable load penetration level on battery sizing parameters. In the second part, a mixed integer programming (MIP) based operation is proposed in this part for residential HVACs. The objective is to minimize the total cost of the HVAC energy consumption under varying electricity prices. A simplied model of a space cooling system considering thermal dynamics is adopted. The optimization problems consider 24-hour operation of HVAC. Comfort/cost trade-o is modeled by introducing a binary variable. The big-M technique is adopted to obtain linear constraints while considering this binary variable. The MIP problems are solved by CPLEX. Simulation results demonstrate the effectiveness of HVAC's ability to respond to varying electricity price. Then, in the final part of this research, two Benders Decomposition strategies are applied to solve a stochastic mixed integer programming (MIP) formulation to obtain the optimal sizing of a photovoltaic system (PV) and battery energy storage system (BESS) to power a residential HVACs. The uncertainty of PV output is modeled using stochastic scenarios with the probability of their occurrence. Total cost including HVAC energy consumption cost and PV/battery installation cost is to be minimized with the system at grid-connected mode over eight hours subject to a varying electricity price. The optimization problem will nd the optimal battery energy capacity, power limit, a number of PV to be installed, and expected HVAC on/o states and BESS charging/discharging states for the next eight hours. This optimization problem is a large-scale MIP problem with expensive computing cost.

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Hashmi, Md Umar. "Optimization and control of storage in smart grids." Thesis, Paris Sciences et Lettres (ComUE), 2019. http://www.theses.fr/2019PSLEE062.

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Cette thèse est motivée par les transformations des systèmes d'énergie électrique, dues à une plus grande intégration des énergies renouvelables et à un modèle de consommation en évolution. Le stockage d'énergie est une solution possible pour faciliter une transition en douceur, garantissant la stabilité du système d’alimentation électrique. Dans cette thèse, la batterie Li-Ion a un double rôle de stockage d'énergie. Premièrement, il est utilisé par les consommateurs individuels pour minimiser le coût de l'électricité. Cela se fait par un arbitrage énergétique basé sur le prix de l'électricité, la correction du facteur de puissance, la réduction de la demande de pointe et la préservation de l'énergie. Ensuite, il est également utilisé pour augmenter la fiabilité et la stabilité du réseau électrique, en effectuant une régulation dynamique et une phase d'équilibrage. Le coût des batteries étant toujours élevé, l’importance est également accordée à la santé de la batterie compte tenu de sa dégradation dans les formulations d’optimisation et de contrôle. Plusieurs études de cas utilisant des données réelles sont menées pour évaluer les performances des algorithmes de contrôle et d’optimisation du stockage. Nous notons que la baisse des prix des batteries et la part croissante des énergies renouvelables intermittentes ne feront qu’augmenter la pertinence de ces travaux pour les futurs réseaux électriques
This thesis is motivated by the electric power system transformations due to more renewable integration and changing consumption patterns. Energy storage is one possible solution to facilitate a smooth transition, ensuring the stability of the power system. In this thesis Li-Ion battery is used both at the level of individual consumers, minimizing the cost of electricity by performing energy arbitrage under time-varying electricity price, power factor correction, peak demand shaving and energy backup, and at the grid level for increasing reliability and stability of the power network by performing dynamic regulation and phase balancing. The cost of the batteries being still high, the importance is also given to the health of the battery taking into account its degradation in optimization and control formulations. Several case studies using real data are conducted to evaluate the performance of the storage control and optimization algorithms. We observe that the ever-decreasing prices of batteries and the growing share of intermittent renewables will only increase the relevance of this work for future power networks

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Clauss, John. "Feasibility study for upgrading the current heat distribution network of an existing building complex to a Smart Thermal Grid." Thesis, KTH, Tillämpad termodynamik och kylteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-173741.

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A feasibility study on upgrading an existing heat distribution network to a low-temperature distribution grid has been carried out during this project. The integration of a solar thermal system combined with a borehole thermal energy storage (BTES) for covering the space heating demand of the buildings as well as the application of CO2 heat pumps and water storage tanks for domestic hot water (DHW) production were investigated in order to apply more renewable energy sources. The energy analysis included several measures, such as modeling the energy demand of the buildings, finding a reasonable number of solar collectors to be installed and dimensioning a ground source heat pump (with the use of CoolPack and Engineering Equation Solver EES) and a geothermal storage (Earth Energy Designer Software EED) as well as CO2 heat pumps (CoolPack/EES). An economic analysis of all proposed measures has been carried out based on the Net Present Value (NPV) and Net Present Value Quotient (NPVQ). Initial costs, annual costs, annual savings as well as the payback time of the energy systems have been calculated. It is found that it is not feasible to invest in the proposed energy system for space heating because the payback time (28 years) of the system is longer than the lifetime of the solar thermal system. Furthermore, the solar gain from the solar collectors is not sufficient for recovering the ground temperature of the BTES with solar energy only which is why external sources would be needed for supplying the remaining energy needed to recover the ground temperature. Results show that an integration of CO2 heat pumps and water storage tanks for DHW production is very promising as the payback time for the investigated system is only 4 years which is why this part should be investigated further.

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Kumar, Deb Nath Uttam. "Electric vehicles in Smart Grids: Performance considerations." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2015. https://ro.ecu.edu.au/theses/1631.

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Distributed power system is the basic architecture of current power systems and demands close cooperation among the generation, transmission and distribution systems. Excessive greenhouse gas emissions over the last decade have driven a move to a more sustainable energy system. This has involved integrating renewable energy sources like wind and solar power into the distributed generation system. Renewable sources offer more opportunities for end users to participate in the power delivery system and to make this distribution system even more efficient, the novel "Smart Grid" concept has emerged. A Smart Grid: offers a two-way communication between the source and the load; integrates renewable sources into the generation system; and provides reliability and sustainability in the entire power system from generation through to ultimate power consumption. Unreliability in continuous production poses challenges for deploying renewable sources in a real-time power delivery system. Different storage options could address this unreliability issue, but they consume electrical energy and create signifcant costs and carbon emissions. An alternative is using electric vehicles and plug-in electric vehicles, with two-way power transfer capability (Grid-to-Vehicle and Vehicle-to-Grid), as temporary distributed energy storage devices. A perfect fit can be charging the vehicle batteries from the renewable sources and discharging the batteries when the grid needs them the most. This will substantially reduce carbon emissions from both the energy and the transportation sector while enhancing the reliability of using renewables. However, participation of these vehicles into the grid discharge program is understandably limited by the concerns of vehicle owners over the battery lifetime and revenue outcomes. A major challenge is to find ways to make vehicle integration more effective and economic for both the vehicle owners and the utility grid. This research addresses problems such as how to increase the average lifetime of vehicles while discharging to the grid; how to make this two-way power transfer economically viable; how to increase the vehicle participation rate; and how to make the whole system more reliable and sustainable. Different methods and techniques are investigated to successfully integrate the electric vehicles into the power system. This research also investigates the economic benefits of using the vehicle batteries in their second life as energy storage units thus reducing storage energy costs for the grid operators, and creating revenue for the vehicle owners.

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CARDUCCI, FRANCESCO. "Tools and methods to study the integration of flexibility assets in the future Smart Grid." Doctoral thesis, Università Politecnica delle Marche, 2018. http://hdl.handle.net/11566/253023.

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Le reti di distribuzione elettrica sono progettate per lavorare sotto regime di equilibrio tra domanda e offerta di energia, ad ogni istante di tempo. Questo vincolo rigido viene oggi messo in crescente difficoltà dall’alta penetrazione di sistemi di generazione basati sulle fonti rinnovabili non programmabili. Il paradigma della Smart Grid offre una soluzione, spostando parte del problema dal lato generazione al lato domanda, riducendo cosi il bisogno di fare affidamento su inquinanti, e costose, centrali di backup termiche. Tramite l’utilizzo coordinato di programmi di demand response, sistemi di energy storage e di generazione distribuita, la Smart Grid può affrontare la variabilità del binomio domanda-generazione, sfruttando un portfolio di assets distribuiti, atti a mettere a disposizione la loro flessibilità. Questa tesi introduce strumenti e metodi che mirano a supportare la comunità scientifica, quella industriale e i policy maker, nel capire il ruolo che gli asset di flessibilit e gli aggregatori avranno nella futura Smart Grid. In particolare, la tesi si concentra su tre tipologie di asset di flessibilità: i sistemi di storage, i carichi termostatici (TCL) e le auto elettriche (EV). Nella prima parte della tesi viene introdotta una definizione di aggregatore, cosi come una architettura di Virtual Power Plant per aggregatori di asset di flessibilità. Dopodiché, una serie di capitoli sono dedicati allo studio dei singoli asset di flessibilità. Il concetto di energy storage equivalente viene usato per introdurre una metodologia di modellazione comune a tutti gli asset, cosi da renderli aggregabili e gestibili in modo coordinato. Infine, il problema della gestione ottimale di un portfolio di asset di flessibilità viene affrontato, offrendo degli approcci matematici alternativi. Una formulazione convessa viene proposta per risolvere il problema dello scheduling ottimale delle risorse, andando a studiare da vicino il problema di un aggregatore interessato alla gestione della domanda energetica di un distretto urbano. Tutte le metodologie presentate sono simulate e testate usando dati di origine eterogenea (sperimentale, privata o pubblica).
Power grids are designed to work under balanced supply and demand at all times. This hard constraint is increasingly challenged by the introduction of higher shares of intermittent renewable generation in the energy generation portfolios of our nations. The Smart Grid paradigm offers to shift part of this problem from the generation to the demand side, reducing the need for polluting, and expensive, peak power plants. Through the usage of demand response programs, energy storage systems and distributed generation sources, the Smart Grid can cope with demand-generation variability leveraging a portfolio of distributed flexibility assets. The main goal of this dissertation is to introduce tools and methods to support the research community, as well as industrial entities and policy makers, understanding the role that flexibility assets and aggregators will play in the future Smart Grid. Here the focus is on three specific types of flexibility assets: energy storage systems, thermostatically controlled loads (TCLs) and electric vehicles (EVs). In the first part of the dissertation, a definition of aggregator is given and a Virtual Power Plant architecture for flexibility assets aggregators is introduced. Then, a series of chapters are dedicated to the single flexibility assets, using the concept of equivalent energy storage to present a common framework to model them and aggregate them. Finally, the optimal portfolio management problem for flexibility assets aggregators is presented, offering alternative mathematical approaches to solve it. A convex formulation is defined to optimally solve the resource scheduling problem, specifically targeting aggregators interested in managing the energy demand of a Urban district. All the methodologies presented are tested using either experimental, private or publicly available data.

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Higgins, Ryan H. "Energy Storage in the Golden State: An Analysis of the Regulatory and Economic Landscape." Scholarship @ Claremont, 2014. http://scholarship.claremont.edu/pomona_theses/105.

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On October 1st, 2013, a mandate was adopted by the California Public Utilities Commission (CPUC) requiring that 1.325 GW of energy storage capability be installed on the California electricity grid by 2024, through the actions of the state’s three investor-owned utilities. While this is a bold first step towards mandated energy storage in the United States, it may be only the beginning for an energy storage industry in this state. It has been well established that energy storage would prove to be a useful asset on the California electrical grid, but the development of storage capacity past the requirements of the mandate will depend upon whether storage can be made cost-effective. Much of the value that storage creates is a public good: many storage applications allow the grid to operate more efficiently as a whole, but not necessarily in a way that can be monetized by any particular party. As a public good, these systemic benefits of storage capacity will be supplied sub-optimally in the absence of government intervention. The energy storage industry will accordingly be one that is strongly affected by the tides of change in technology, regulation and economics in the California energy market. This report will focus primarily on the intersection of the second two of these factors, largely leaving the technological questions to more well-informed parties while seeking to establish what regulatory and economic considerations might be undertaken to ensure that the road to deployment of appropriate energy storage systems is made as clear as possible so that this technology can reach the socially efficient level on the California electricity grid. It is the aim of this report not to promote a specific technology or even an energy storage industry, but rather to shed some light on the effects that the development of such an industry could have on the California electricity market and the energy use paradigm that governs modern electricity grids worldwide. With the adoption of AB 2514, a grand experiment was set in motion that will benefit the entire world as California tests the uncharted technological, regulatory and economic territories of grid-scale energy storage capacity. It is a time of change in the electricity industry, and energy storage is a potentially transformative technology that could very well enable the shattering of an energy use paradigm that has held the world captive to fossil fuels for over a century.

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Du, Plooy Henri. "Comparative strategies for efficient control and storage of renewable energy in a microgrid." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2486.

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Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2016.
Power fluctuations in a microgrid are caused by disturbances due to the connection and disconnection of Distributed Generators (DG’s), as well as the irregular input of the sun and wind renewable energy. Renewable penetration such as the sun, wind and tidal energy causes intermittency which directly affects the input and resultant output power of a microgrid. Control systems have to be implemented on three different levels to ensure the stability and reliability of the power supplied to the load. This can be achieved by implementing the following: 1) Primary control with mechanical valves and actuators to translate feedback signals through droop control. 2) Secondary control with power electronics to facilitate maximum power point tracking, phase lock loops and switch mode inverters to manipulate the electrical signals to a desired set points including PID control. 3) Tertiary control with software program management to monitor the power flow as well as to evaluate congregated logic and implement decision making. Energy storage systems like super capacitors can compensate for power imbalance by providing excess stored energy to the microgrid for short periods of time. The added advantage of capacitor banks is that it can facilitate power factor correction where inductive loads like rotating motors form large part of the total load. Battery banks can compensate for energy shortage for longer periods of time. The duration of the compensation can be determined by the size, topology and the type of batteries used. The objectives of this study is to improve the unstable power output responses of a renewable energy microgrid by designing and analysing control strategies intended at power wavering compensation which also includes energy storage. Sub control systems is created and simulated in Matlab/Simulink for analytical comparative observations. Results of the simulated model are discussed and recommendations are given for future works.

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Gustafsson, Amelie, and Hannes Wiklund. "Batterier i kraftsystemet : En studie i batteriers potential som energilagring för stöd av intermittenta energikällor i det nationella kraftsystemet." Thesis, KTH, Hållbar utveckling, miljövetenskap och teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-255867.

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Utveckling av det moderna samhället och den fortsatt accelererande energiintensiva tillvaro människan lever i sätter stor press på klimatet. För att nå de hållbarhetsmål FN satt upp som bland annat innebär minskade utsläpp och effektivare energianvändning krävs krafttag i det globala energisystemet. För att öka andelen modern och ren energi krävs att sol- och vindkraft prioriteras. Ett stort problem med dessa energikällor är dess intermittenta produktion vilken alstrar oregelbunden elektricitet och ställer nya krav på elnätet. För att underlätta implementering av förnybara energikällor på det nationella elnätet och i mindre energisystem undersöks i den här rapporten de förutsättningar som finns för att integrera batterienergilagringssystem i kombination med intermittenta energikällor. Rådande förutsättningar redogörs för i en omfattande litteraturundersökning där bland annat elnätets funktion, lovande batteriteknologier, ekonomiska incitament för batterienergilagring och framtidspotential undersöks. Ett globalt engagemang för att öka andelen förnybar energi med hjälp av batterienergilagring i det globala energisystemet identifieras. Vidare visas batterienergilagringssystem har stor potential att minimera den belastning intermittenta energikällor har på elnätet. Potentialen begränsas i nuläget av rådande politiska styrmedel och elmarknadens utformning då en småskalig elproducent idag gynnas av att direkt mata ut överskottsel på elnätet istället för att använda energilagring. Med en växande andel intermittent elproduktion förväntas minskade begränsningar och batterienergilagring kopplat till elproduktion bli mer lönsamt.
The development of the modern society and the global continuously accelerating energy intensive way of living is putting stress on the climate. In order to achieve the UNs set of sustainability goals, including reduced emissions and more efficient use of energy, vigorous actions in the global energy system is required. To increase the share of clean and modern energy generation a larger quantity of solar and wind power is required. Due to weather dependency these resources generate intermittent electricity which will put new challenges on the grid. To facilitate the implementation of intermittent energy sources on the national grid and in smaller energy systems this report aims to investigate current prerequisites on integrating battery energy storage systems and intermittent resources to increase the share of clean energy sources in the power system. Current prerequisites are presented as the result of an extensive literature study where the electrical grid, promising battery technologies, financial incentives for battery energy storage and future potential is examined. A global commitment to increase the share of renewable energy sources using battery energy storage system in the global energy system is identified. Furthermore, battery energy storage systems are shown to have great potential in limiting the negative impact of intermittent energy sources on the electrical grid. This potential is currently being limited by existing political control means and the design of the electricity market such that small producers are benefitted by directly supplying the grid with excess electricity instead of using energy storage. With a growing share of intermittent power generation these limitations are expected to ease and battery energy storage systems in connection with power production becoming more profitable.

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Kim, Rae-Young. "Improved renewable energy power system using a generalized control structure for two-stage power converters." Diss., Virginia Tech, 2009. http://hdl.handle.net/10919/28932.

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The dissertation presents a generalized control structure for two-stage power converters operated in a renewable energy power system for smart grid and micro grid systems. The generalized control structure is based on the two-loop average-mode-control technique, and created by reconstructing the conventional control structure and feedback configuration. It is broadly used for both dc-dc and dc-ac power conversion based on the two-stage converter architecture, while offering several functionalities required for renewable energy power systems. The generalized control structure improves the performance and reliability of renewable energy power systems with multiple functionalities required for consistent and reliable distributed power sources in the applications of the smart grid and micro grid system. The dissertation also presents a new modeling approach based on a modification of the subsystem-integration approach. The approach provides continuous-time small-signal models for all of two-stage power converters in a unified way. As a result, a modeling procedure is significantly reduced by treating a two-stage power converter as a single-stage with current sinking or sourcing. The difficulty of linearization caused by time-varying state variables is avoided with the use of the quasi-steady state concept. The generalized control structure and modeling approach are demonstrated using the two-stage dc-dc and dc-ac power conversion systems. A battery energy storage system with a thermoelectric source and a grid-connected power system with a photovoltaic source are examined. The large-signal averaged model and small-signal model are developed for the two demonstrated examples, respectively. Based on the modeling results, the control loops are designed by using frequency domain analysis. Various simulations and experimental tests are carried out to verify the compensator designs and to evaluate the generalized control structure performance. From the simulation and experimental results, it is clearly seen that the generalized control structure improves the performance of a battery energy storage system due to the unified control concept. The unified control concept eliminates transient over-voltage or over-current, extra energy losses, power quality issues, and complicated decision processes for multiple-mode control. It is also seen that the generalized control structure improves the performance of a single-phase grid-connected system through increased voltage control loop bandwidth of the active ripple current reduction scheme. As a result of the increased loop bandwidth, the transient overshoot or undershoot of the dc-link voltage are significantly reduced during dynamic load changes.
Ph. D.

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CARAVELLO, Giuseppe. "Study, project and implementation of new metrics for distributed measurement system in medium voltage smart grid." Doctoral thesis, Università degli Studi di Palermo, 2022. http://hdl.handle.net/10447/534761.

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Sehar, Fakeha. "An Approach to Mitigate Electric Vehicle Penetration Challenges through Demand Response, Solar Photovoltaics and Energy Storage Applications in Commercial Buildings." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/86654.

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Electric Vehicles (EVs) are active loads as they increase the demand for electricity and introduce several challenges to electrical distribution feeders during charging. Demand Response (DR) or performing load control in commercial buildings along with the deployment of solar photovoltaic (PV) and ice storage systems at the building level can improve the efficiency of electricity grids and mitigate expensive peak demand/energy charges for buildings. This research aims to provide such a solution to make EV penetration transparent to the grid. Firstly, this research contributes to the development of an integrated control of major loads, i.e., Heating Ventilation and Air Conditioning (HVAC), lighting and plug loads while maintaining occupant environmental preferences in small- and medium-sized commercial buildings which are an untapped DR resource. Secondly, this research contributes to improvement in functionalities of EnergyPlus by incorporating a 1-minute resolution data set at the individual plug load level. The research evaluates total building power consumption performance taking into account interactions among lighting, plug load, HVAC and control systems in a realistic manner. Third, this research presents a model to study integrated control of PV and ice storage on improving building operation in demand responsive buildings. The research presents the impact of deploying various combinations of PV and ice storage to generate additional benefits, including clean energy generation from PV and valley filling from ice storage, in commercial buildings. Fourth, this research presents a coordinated load control strategy, among participating commercial buildings in a distribution feeder to optimally control buildings' major loads without sacrificing occupant comfort and ice storage discharge, along with strategically deployed PV to absorb EV penetration. Demand responsive commercial building load profiles and field recorded EV charging profiles have been added to a real world distribution circuit to analyze the effects of EV penetration, together with real-world PV output profiles. Instead of focusing on individual building's economic benefits, the developed approach considers both technical and economic benefits of the whole distribution feeder, including maintaining distribution-level load factor within acceptable ranges and reducing feeder losses.
Ph. D.

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Weingarten, Leopold. "Physical Hybrid Model : Measurement - Experiment - Simulation." Thesis, Uppsala universitet, Fasta tillståndets fysik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-176412.

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A method has been developed, Physical Hybrid Model, to investigate the physical large scale electrical effects of a Battery Energy Storage System (BESS) on a distribution grid by scaling the response from a small size Research Development and Demonstration (RD&D) platform. In order to realize the model the control system of an existing RD&D platform was refurbished and stability of components ensured. The Physical Hybrid Model proceeds as follows: Data from a distribution grid are collected. A BESS cycle curve is produced based on analyzed measurements. Required BESS power and capacity in investigated grid is scaled down by factor k to that of the physical test installation of the RD&D platform. The scaled BESS cycle is sent as input to control of the battery cycling of the RD&D platform. The response from the RD&D platform is scaled – up, and used in simulation of the distribution grid to find the impact of a BESS. The model was successfully implemented on a regional distribution grid in southern Sweden.

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Carradore, Loredana. "Modeling and Management of Smart Energy Networks." Doctoral thesis, Università degli studi di Padova, 2011. http://hdl.handle.net/11577/3427462.

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"Smart grids'' identifies what future electrical network would represent: an intelligent integrated system where every device available to modify their generation/absorption is responsive, awaken of its role, eco-sensitive, flexible and interconnected with others. In this scenario, smart technologies, such as Information and Communication Technologies and smart meters, will allow interconnections and interactions among these devices that are available to participate in ancillary services; whereas a smart management system would ensure quality, reliability, efficiency, effectiveness in the supply service and the free participation in services for the grid support of these new customers. However, even if the smart grid scenario seems to be clearly defined, investigation on the management system is still required, in order to efficiently co-ordinate all distributed resources in distribution networks and to exploit the potentiality of new possible participants in the network regulation, such us energy storage devices and electrical vehicles. By the way, energy markets seem to be ideally suited to support the system operator in the co-ordination of different energy resources, also allowing the exploitation of synergy among different energy carries to increase the overall efficiency and reliability of the system. In fact, energy markets could create suitable price signals able to make responsive devices available to modify their generation/absorption to network requirements. For this reason, it seems reasonable to refer to these devices as customers. Investigations on smart management procedures for the co-ordination of different resources in energy networks is the main thread of this thesis. In particular, the importance of price signals to obtain a virtuous behavior of customers has been exploited, focusing on co-ordinated management procedures, in order to ensure the management of the complex electrical network system. In the first chapter a brief introduction to smart grids, energy markets and storage devices is provided, in order to present general background and motivation of this work. The modeling basis of the software environment developed during the PhD and used to investigate management issues in smart energy network are presented in chapter 2. Chapter 3 presents preliminary investigations on energy hub, a generation, conversion and storage center, management based on suitable price signals to optimally manage exchanges of flows among different energy vectors, in order to exploit synergy properties. In chapter 4, investigation on the management of a multi-energy vector systems through price coefficients is presented. In particular, price coefficients proportional to reference signals, that represents network requirements, have been analyzed in a decoupled management procedure between network and energy hubs with storage devices. In chapter 5, it is described how to exploit this decoupled optimisation procedure, considering aggregators of EVs as flexible distributed storage devices. In chapter 6, an innovative management procedure based on token ring philosophy, aimed to co-ordinate distributed resources, ensuring their free participation in services for the grid support is proposed. The thesis ends with chapter 7, where the most important achievements and suggests in possible future work are summarizes and discusses.
Con "smart grids'' si può identificare quello che rappresenteranno le reti elettriche del futuro, ovvero un sistema integrato ed intelligente, dove ogni dispositivo disponibile a modificare la propria generazione e il proprio assorbimento, è reattivo, attento ai segnali di prezzo, consapevole del proprio ruolo, sensibile agli aspetti ambientali, flessibile e interconnesso con gli altri. In questo scenario, tecnologie intelligenti, come i sistemi ICT (Information and Communication Technologies) e gli smart meter, permetteranno le interconnesioni e le interazioni tra questi dispositivi disponibili a partecipare nei servizi ancillari; mentre un sistema di gestione intelligente dovrebbe essere in grado di assicurare qualità, affidabilità, efficienza, efficacia nel servizio di fornitura e la libera partecipazione nei servizi per il supporto della rete di questi nuovi clienti. Sebbene lo scenario identificato dal termine "smart grids'' sembri essere chiaramente definito, risulta ancora necessario lo studio relativo al sistema di gestione fondamentale per coordinare in maniera efficiente le risorse distribuite nelle reti di distribuzione e le potenzialità introdotte da nuovi possibili participanti nella regolazione della rete, come per esempio i sistemi di accumulo e i veicoli elettrici. A questo proposito, i mercati energetici sembrano ideali per aiutare l'operatore di sistema a coinvolgere tutte le risorse energetiche nella regolazione della rete, permettendo anche lo sfruttamento della singergia tra differenti vettori energetici, allo scopo di incrementare l'efficienza e l'affidabilità generale di tutto il sistema. Infatti, i mercati energetici possono creare appropriati segnali di prezzo in grado di rendere sensibili alle esigenze della rete quei dispositivi disponibili a modificare la loro generazione e il loro assorbimento. È per questo motivo che sembra opportuno identificare questi dispositivi come clienti. Il principale filo conduttore di questa tesi è stato la ricerca di procedure intelligenti di gestione per la coordinazione di differenti risorse nelle future reti energetiche intelligenti. In particolare, è stata sfruttata l'idea chiave dell'importanza dei segnali di prezzo per ottenere un comportamento virtuoso dei clienti, concentrandosi su metodi di coordinamento in grado di assicurare con meccanismi semplici la gestione di un complesso sistema come quello della rete elettrica. Nel primo capitolo di questa tesi è presente una breve introduzione alle smart grids, ai mercati energetici e ai sistemi di accumulo, al solo scopo di presentare background e motivazioni di questo lavoro. Il capitolo 2 raccoglie le basi teoriche della modellizzazione dell'ambiente software sviluppato durante il dottorato e usato per studiare la gestione in reti energetiche intelligenti. Il capitolo 3 presenta le prime indagini sulla gestione di un energy hub, un centro di generazione, conversione e assorbimento, basata su segnali di prezzo adeguati a permettere una gestione ottima di flussi tra differenti vettori energetici, in modo da sfruttare la loro sinergia. Il capitolo 4 riporta quanto studiato per la gestione di un sistema multi-vettore energetico attraverso coefficienti di prezzo. In particolare, è stata analizzata la possibilità di utilizzare termini di prezzo proporzionali ad un segnale di riferimento che rappresenti la richiesta della rete in una gestione disaccoppiata di rete ed energy hub con sistemi di accumulo. Questa precudura di ottimizzazione disaccoppiata è stata applicata nel capitolo 5 a degli agglomerati di veicoli elettrici, intesi come sistemi di accumulo flessibili e distribuiti. Nel capitolo 6, infine, viene presentata un'innovativa procedura di gestione, basata sulla filosofia del token ring, mirata a coordinare risorse distribuite assicurando la loro libera partecipazione nei servizi per il supporto della rete. La tesi si chiude con il capitolo 7, che riassume e discute i più importanti traguardi raggiunti e suggerendo possibili lavori futuri.

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Granado, Pedro Crespo del. "The value of energy storage from intermittent renewables : an end user perspectives in Smart Grids." Thesis, Lancaster University, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.732707.

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The widespread deployment of renewable energy in combination with smart grid technologies is creating the opportunity for energy storage to play a critical role in energy systems and be a more prevalent technology in the near future. This research adopts a bottom-up approach to model the interactions within the energy system, namely between renewable supply and storage technologies at the end-user level (e.g. in houses, buildings and communities). That is, the papers presented in this thesis investigate the value of energy storage in smart grids from an end-user perspective. Specifically, it focuses on the role of storage units in the regulation of the energy system’s supply-demand balance and the cost savings for the end-user. Hence, the contribution of this study lies in the perspective taken (end-user), as well as in the models developed for the valuation of energy storage. In this sense, it provides an understanding of different aspects associated with the valuation of storage technologies in smart grids. Particular attention is paid to the contribution of local wind energy supply as well as demand response (smart grids). Analytics data-driven optimization is central in this research. To analyze the interactions on complementing energy storage with decentralized energy system in smart grids, this thesis develops models for two real-life case studies: The first paper assess the value of batteries in domestic houses in sync with on-site renewable micro generation. A second paper extends the research, bottom-up, to a community dependent on its own hybrid decentralized generation coupled with energy storage units. As uncertainty of wind generation is not considered in these cases, a third paper investigates the storage valuation by a stochastic programming approach.

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Leppin, Lorenz. "Development of Operational Strategies for a Heating Pump System with Photovoltaic, Electrical and Thermal Storage." Thesis, Högskolan Dalarna, Energiteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:du-27304.

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This study describes the development of operational strategies for an exhaust air heat pump system that supplies space heating and domestic hot water. The system combines photovoltaic power production with two different storage types. These are electrical storage using batteries and thermal storage in using a domestic hot water tank and in form of the thermal capacity of the building. The investigation of the control strategies is carried out for a detailed single family house model in Sweden in the simulation software TRNSYS. The overall aim of the control strategies is to improve the performance of the energy system in terms of self-consumption, self-sufficiency, final energy and seasonal performance factor. Three algorithms are developed and compared to a base case without additional control. The first algorithm only uses the thermal storage in the hot water tank and the building. The second uses only the battery to store the photovoltaic electricity. The third control algorithm combines both storage types, electrical and thermal. The simulation results show that for the studied system the energetic improvement is higher with the use of electrical storage compared to using thermal storage. The biggest improvement however is reached with the third algorithm, using both storage types in combination. For the case of a photovoltaic-system with 9 kW and battery store with 10.8 kWh and a 180 l hot water store the self-consumption reaches up to 51% with a solar fraction of 41 %. The reduction in final energy consumption for this case is 3057 kWh (31 %) with the heat pump having a seasonal performance factor of 2.6. The highest self-consumption is reached with a photovoltaic-system of 3 kW and battery store with 3.6 kWh, which comes to 71 %.

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Forsmark, Anders, and Tim Sidemark. "Anslutning av vindkraft till ett svagt nät i Tidaholm." Thesis, Högskolan Väst, Avd för elektro- och automationsteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-4148.

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Vindkraftverk ansluts idag i snabb takt till elnät runt om i världen. Elnäten är ofta inte tillräckligt dimensionerade på platser där vindkraftutbyggnad är lämplig vilket leder till ett behov av nätförstärkning. Förstärkning sker konventionellt genom att övergå till en högre spänning, något som kan vara förenat med stora kostnader och ledtider. Bland annat därför har en filosofi med beteckningen smarta elnät uppstått, som handlar om hur elnätsystemet ska se ut när det är mer anpassat till de nya energikällornas karaktär och samtidigt medför ett mer effektivt totalutnyttjande. För vindkraftverk kan det då handla om att i högre grad än idag reglera produktionen och understödja nätet, t.ex. via intelligenta kontrollsystem, kraftelektronik och energilager. I den här rapporten undersöks hur mycket vindkraft som kan anslutas till ett svagt elnät då principer för smarta elnät tillämpas och för att se om kostnaden blir lägre än anslutning via konventionella nätförstärkningsmetoder. Det svaga elnätet som studien bygger på ligger i Tidaholm. Vindkraftseffekten som ska anslutas är på 62 MW. Begränsningar i befintliga regionnätets ledningar gör att 60,3 MW kan anslutas med principer för smarta elnät, fast det finns flera skäl till att anta att den fulla mängden vindkraft går att ansluta. Detta till en kostnad som väsentligt understiger kostnaden att förstärka nätet på konventionellt sätt, kostnadsbesparingen uppgår till ca 58 % eller ca 95 Mkr.

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Alfadda, Abdullah Ibrahim A. "Strategies for Managing Cool Thermal Energy Storage with Day-ahead PV and Building Load Forecasting at a District Level." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/93509.

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In hot climate areas, the electrical load in a building spikes, but not by the same amount daily due to various conditions. In order to cover the hottest day of the year, large cooling systems are installed, but are not fully utilized during all hot summer days. As a result, the investments in these cooling systems cannot be fully justified. A solution for more optimal use of the building cooling system is presented in this dissertation using Cool Thermal Energy Storage (CTES) deployed at a district level. Such CTES systems are charged overnight and the cool charge is dispatched as cool air during the day. The integration of the CTES helps to downsize the otherwise large cooling systems designed for the hottest day of the year. This reduces the capital costs of installing large cooling systems. However, one important question remains - how much of the CTES should be charged during the night, such that the cooling load for the next day is fully met and at the same time the CTES charge is fully utilized during the day. The solution presented in this dissertation integrated the CTES with Photovoltaics (PV) power forecasting and building load forecasting at a district level for a more optimal charge/discharge management. A district comprises several buildings of different load profiles, all connected to the same cooling system with central CTES. The use of forecasting for both the PV and the building cooling load allows the building operator to more accurately determine how much of the CTES should be charged during the night, such that the cooling system and CTES can meet the cooling demand for the next day. Using this approach, the CTES would be optimally sized, and utilized more efficiently during the day. At the same time, peak load savings are achieved, thus benefiting an electric utility company. The district presented in this dissertation comprises PV panels and three types of buildings – a mosque, a clinic and an office building. In order to have a good estimation for the required CTES charge for the next day, reliable forecasts for the PV panel outputs and the electrical load of the three buildings are required. In the model developed for the current work, dust was introduced as a new input feature in all of the forecasting models to improve the models' accuracy. Dust levels play an important role in PV output forecasts in areas with high and variable dust values. The overall solution used both the PV panel forecasts and the building load forecasts to estimate the CTES charge for the next day. The presented method was tested against the baseline method with no forecasting system. Multiple scenarios were conducted with different cooling system sizes and different CTES capacities. Research findings indicated that the presented method utilized the CTES charge more efficiently than the baseline method. This led to more savings in the energy consumption at the district level.
Doctor of Philosophy
In hot weather areas around the world, the electrical load in a building spikes because of the cooling load, but not by the same amount daily due to various conditions. In order to meet the demand of the hottest day of the year, large cooling systems are installed. However, these large systems are not fully utilized during all hot summer days. As a result, the investments in these cooling systems cannot be fully justified. A solution for more optimal use of the building cooling system is presented in this dissertation using Cool Thermal Energy Storage (CTES) deployed at a district level. Such CTES systems are charged overnight and the cool charge is dispatched as cool air during the day. The integration of the CTES helps to downsize the otherwise large cooling systems designed for the hottest day of the year. This reduces the capital costs of installing large cooling systems. However, one important question remains - how much of the CTES should be charged during the night, such that the cooling load for the next day is fully met and at the same time the CTES charge is fully utilized during the day. The solution presented in this dissertation integrated the CTES with Photovoltaics (PV) power forecasting and building load forecasting at a district level for a more optimal charge/discharge management. A district comprises several buildings all connected to the same cooling system with central CTES. The use of the forecasting for both the PV and the building cooling load allows the building operator to more accurately determine how much of the CTES should be charged during the night, such that the cooling system and CTES can meet the cooling demand for the next day. Using this approach, the CTES would be optimally sized and utilized more efficiently. At the same time, peak load is lowered, thus benefiting an electric utility company.

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Hubert, Tanguy Fitzgerald. "Design and implementation of a software tool for day-ahead and real-time electricity grid optimal management at the residential level from a customer's perspective." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/41188.

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This thesis focuses on the design and implementation of a software tool able to achieve electricity grid optimal management in a dynamic pricing environment, at the residential level, and from a customer's perspective. The main drivers encouraging a development of energy management at the home level are analyzed, and a system architecture modeling power, thermodynamic and economic subsystems is proposed. The user behavior is also considered. A mathematical formulation of the related energy management optimization problem is proposed based on the linear programming theory. Several cases involving controllable and non-controllable domestic loads as well as renewable energy sources are presented and simulation scenarios illustrate the proposed optimization strategy in each case. The performance of the controller and the changes in energy use are analyzed, and ideas for possible future work are discussed.

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Raffa, Viviana. "Edge/cloud virtualization techniques and resources allocation algorithms for IoT-based smart energy applications." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/22864/.

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Nowadays, the installation of residential battery energy storage (BES) has increased as a consequence of the decrease in the cost of batteries. The coupling of small-scale energy generation (residential PV) and residential BES promotes the integration of microgrids (MG), i.e., clusters of local energy sources, energy storages, and customers which are represented as a single controllable entity. The operations between multiple grid-connected MGs and the distribution network can be coordinated by controlling the power exchange; however, in order to achieve this level of coordination, a control and communication MG interface should be developed as an add-on DMS (Distribution Management System) functionality to integrate the MG energy scheduling with the network optimal power flow. This thesis proposes an edge-cloud architecture that is able to integrate the microgrid energy scheduling method with the grid constrained power flow, as well as providing tools for controlling and monitoring edge devices. As a specific case study, we consider the problem of determining the energy scheduling (amount extracted/stored from/in batteries) for each prosumer in a microgrid with a certain global objective (e.g. to make a few energy exchanges as possible with the main grid). The results show that, in order to have better optimization of the BES scheduling, it is necessary to evaluate the composition of a microgrid in such a way as to have balanced deficits and surpluses, which can be performed with Machine Learning (ML) techniques based on past production and consumption data for each prosumer.

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Kuriakose, Jaise. "The resilience of low carbon electricity provision to climate change impacts : the role of smart grids." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/the-resilience-of-low-carbon-electricity-provision-to-climate-change-impacts-the-role-of-smart-grids(c139ce36-d73c-4d8b-913e-f66826496405).html.

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The UK’s decarbonisation strategy to increasingly electrify heating and transport will change the demand requirement on the electricity system. Additionally, under a climate change future, it is projected that the decarbonised grid will need to be able to operate under higher average temperatures in the UK, increasing the need for comfort cooling during summer and leading to additional electricity demand. These new demands will result in greater variation between minimum and peak demand as well as a significant increase in overall demand. Concurrently, supply-side decarbonisation programmes may lead to more intermittent renewables such as wind, PV, tidal and wave, elevating variability in electricity generation. Coupled with the anticipated higher variation in demand this brings on several challenges in operating the electricity grid. In order to characterise these challenges this research develops a bespoke electricity dispatch model which builds on hourly models of demand and generation. The hourly demand profiles are based on a high electrification of heating, transport and cooling coupled with future temperatures premised on the UKCP09 high emission scenario climate projections. The demand profiles show a significant increase in peak demand by 2050 reaching 194 GW, mainly due to summer cooling loads which contribute 70% of the demand. The cumulative CO2 emissions budgets of the GB power sector that are consistent with avoiding global climate change to 2°C are used to develop two low carbon generation scenarios distinguished by the amount of intermittent renewable generation technologies. The dispatch model tests the capability of generation scenarios with the use of hourly generation models in meeting future demand profiles out to 2050.The outputs from dispatch model indicate that there are shortages and excesses of generation relative to demand from 2030 onwards. The variability analysis outlines low and high generation periods from intermittent technologies along with the pace at which intermittent generation increases or decreases within an hour. The characterisation of variability analysis reveals the type of reserve capacity or smart solutions that are required to maintain the security of electricity supply. The solutions that could address the challenges quantified from the model outputs in operating a decarbonised GB electricity grid are explored using expert interviews. The analysis of the stakeholder interviews suggests smart grid solutions that include technologies as well as changes in operational procedures in order to enhance the operational resilience of the grid. Active Network Management through monitoring and control, demand management, storage systems and interconnectors are proposed to address challenges arising from varying demand and generation variability.

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Gensollen, Nicolas. "Modeling and optimizing a distributed power network : a complex system approach of the "prosumer" management in the smart grid." Thesis, Evry, Institut national des télécommunications, 2016. http://www.theses.fr/2016TELE0019/document.

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Cette thèse est consacrée à l'étude d’agents appelés prosumers parce qu’ils peuvent, à partir d’énergies renouvelables, à la fois produire et consommer de l’électricité. Si leurs productions excèdent leurs propres besoins, ceux-ci cherchent à vendre leur surplus sur des marchés de l’électricité. Nous proposons de modéliser ces prosumers à partir de données météorologiques, ce qui nous a permit de mettre en évidence des corrélations spatio-temporelles non triviales, d'une grande importance pour les agrégateurs qui forment des portefeuilles d’équipements afin de vendre des services à l'opérateur du réseau. Comme un agrégateur est lié par un contrat avec l'opérateur, il peut faire l'objet de sanctions s’il ne remplit pas son rôle. Nous montrons que ces corrélations impactent la stabilité des agrégats, et donc le risque encouru par les agrégateurs. Nous proposons un algorithme minimisant le risque d'un ensemble d’agrégations, tout en maximisant le gain attendu. La mise en place de dispositifs de stockage dans un réseau où les générateurs et les charges sont dynamiques et stochastiques est complexe. Nous proposons de répondre à cette question grâce à la théorie du contrôle. Nous modélisons le système électrique par un réseau d'oscillateurs couplés, dont la dynamique des angles de phase est une approximation de la dynamique réelle du système. Le but est de trouver le sous-ensemble des nœuds du graphe qui, lors d'une perturbation du système, permet le retour à l'équilibre si les bons signaux sont injectés, et ceci avec une énergie minimum. Nous proposons un algorithme pour trouver un placement proche de l'optimum permettant de minimiser l'énergie moyenne de contrôle
This thesis is devoted to the study of agents called prosumers because they can, from renewable, both produce and consume electricity. If their production exceeds their own needs, they are looking to sell their surplus on electricity markets. We propose to model these prosumers from meteorological data, which has allowed us to highlight non trivial spatial and temporal correlations. This is of great importance for aggregators that form portfolios of equipments to sell services to the network operator. As an aggregator is bound by a contract with the operator, it can be subject to penalties if it does not fulfill its role. We show that these correlations impact the stability of aggregates, and therefore the risk taken by the aggregators. We propose an algorithm minimizing the risk of the aggregations, while maximizing the expected gain. The placement of storage devices in a network where generators and loads are stochastic and not fixed is complex. We propose to answer this question with control theory. We model the electrical system as a network of coupled oscillators, whose phase angles dynamics is an approximation of the actual dynamics of the system. The goal is to find the subset of nodes in the graph that, during a disturbance of the system, allows returning to equilibrium if the right signals are injected and this with a minimum energy. We propose an algorithm to find a near optimal placement to minimize the average energy control

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Behnood, Aref. "Optimal Operation of Battery Energy Storage Systems in Radial Distribution Networks." Thesis, Uppsala universitet, Elektricitetslära, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-397113.

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In recent years, power systems are facing with various challenges arising from the increased share of renewable energy systems. Among all sections of power systems, distribution grids are affected the most since the majority of renewable energy sources are connected to distribution grids. As the penetration of Variable Energy Sources increases in electric grids, energy storage systems have become more influential. In this context, this thesis presents a new algorithm for the optimal operation of Battery Energy Storage Systems in distribution grids. The proposed algorithm aims to define the optimal operation of Battery Energy Storage Systems considering the network topology, the output power of Variable Energy Sources and the electricity prices from the one-day ahead electric market as well as real time control of the batteries through smart appliances. In order to do this, firstly a comprehensive study on the existing Optimal Power Flow methods is carried out. Then, AR-OPF which is a novel Optimal Power Flow method for radial distribution systems is presented and the required mathematical constraints, equations and parameters of Battery Energy Storage Systems for modelling in distribution systems are described. Then, the problem formulation and the proposed algorithm are discussed in detail. Further to energy storage as the main function of Battery Energy Storage Systems, the impact of the proposed method on other functions of Battery Energy Storage Systems such as voltage control, grid support and loss reduction will be investigated. In order to do so, the proposed algorithm is applied to the IEEE 34 node test system as a case study. This will be carried out through defining several different scenarios. Finally, a sensitivity analysis is performed on the size of the existing batteries and the electricity price. The thesis will be concluded by the findings and possible future works.

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Lakshminarayanan, Srivathsan. "Nature Inspired Grey Wolf Optimizer Algorithm for Minimizing Operating Cost in Green Smart Home." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1438102173.

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Teske, Sven [Verfasser]. "Bridging the Gap between Energy- and Grid Models : developing an integrated infrastructural planning model for 100% renewable energy systems in order to optimize the interaction of flexible power generation, smart grids and storage technologies / Sven Teske." Flensburg : Zentrale Hochschulbibliothek Flensburg, 2015. http://d-nb.info/1076377955/34.

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Etherden, Nicholas. "Increasing the hosting capacity of distributed energy resources using storage and communication." Doctoral thesis, Luleå tekniska universitet, Energivetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18490.

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This thesis develops methods to increase the amount of renewable energy sources that can be integrated into a power grid. The assessed methods include i) dynamic real-time assessment to enable the grid to be operated closer to its design limits; ii) energy storage and iii) coordinated control of distributed production units. Power grids using such novel techniques are referred to as “Smart Grids”. Under favourable conditions the use of these techniques is an alternative to traditional grid planning like replacement of transformers or construction of a new power line. Distributed Energy Resources like wind and solar power will impact the performance of the grid and this sets a limit to the amount of such renewables that can be integrated. The work develops the hosting capacity concept as an objective metric to quantify the ability of a power grid to integrate new production. Several case studies are presented using actual hourly production and consumption data. It is shown how the different variability of renewables and consumption affect the hosting capacity. The hosting capacity method is extended to the application of storage and curtailment. The goal is to create greater comparability and transparency, thereby improving the factual base of discussions between grid operators, electricity producers and other stakeholders on the amount and type of production that can be connected to a grid.Energy storage allows the consumption and production of electricity to be decoupled. This in turn allows electricity to be produced as the wind blows and the sun shines while consumed when required. Yet storage is expensive and the research defines when storage offers unique benefits not possible to achieve by other means. Focus is on comparison of storage to conventional and novel methods.As the number of distributed energy resources increase, their electronic converters need to provide services that help to keep the grid operating within its design criteria. The use of functionality from IEC Smart Grid standards, mainly IEC 61850, to coordinate the control and operation of these resources is demonstrated in a Research, Development and Demonstration site. The site contains wind, solar power, and battery storage together with the communication and control equipment expected in the future grids.Together storage, new communication schemes and grid control strategies allow for increased amounts of renewables into existing power grids, without unacceptable effects on users and grid performance.
Avhandlingen studerar hur existerande elnät kan ta emot mer produktion från förnyelsebara energikällor som vindkraft och solenergi. En metodik utvecklas för att objektivt kvantifiera mängden ny produktion som kan tas emot av ett nät. I flera fallstudier på verkliga nät utvärderas potentiella vinster med energilager, realtids gränser för nätets överföringsförmåga, och koordinerad kontroll av småskaliga energiresurser. De föreslagna lösningarna för lagring och kommunikation har verifierats experimentellt i en forskning, utveckling och demonstrationsanläggning i Ludvika.
Godkänd; 2014; Bibliografisk uppgift: Nicholas Etherden är industridoktorand på STRI AB i Göteborg. Vid sidan av doktoreringen har Nicholas varit aktiv som konsult inom kraftsystemsautomation och Smarta Elnät. Hans specialitet är IEC 61850 standarden för kommunikation inom elnät, vindkraftparker och distribuerad generering. Författaren har en civilingenjörsexamen i Teknisk fysik från Uppsala Universitet år 2000. Under studietiden läste han även kurser i kemi, miljökunskap och teoretisk filosofi. Han var under studietiden ordförande för Student Pugwash Sweden och ledamot International Network of Engineers and of Scientists for Global Responsibility (INES). Efter studietiden var han ordförande i Svenska Forskare och Ingenjörer mot Kärnvapen (FIMK). Han började sin professionella bana som trainee på ABB i Västerås där han spenderade sex år som utvecklare och grupp ledare för applikationsutvecklingen i ABB reläskydd. I parallell till arbete har han läst elkraft vid Mälardalenshögskola. År 2008 började han på STRI AB som ansvarig för dess IEC 61850 interoperabilitetslab. Han är på uppdrag av Svenska Kraftnät aktiv i ENTSO-E IEC 61850 specificeringsarbete och svensk representant i IEC tekniska kommitté 57, arbetsgrupp 10 som förvaltar IEC 61850 standarden. Han har hållit över 30 kurser i IEC 61850 standarden i fler än 10 länder.; 20140218 (niceth); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Nicholas Etherden Ämne: Elkraftteknik/Electric Power Engineering Avhandling: Increasing the Hosting Capacity of Distributed Energy Resources Using Storage and Communication Opponent: Professor Joao A Peças Lopes, Faculty of Engineering of the University of Porto, Portugal Ordförande: Professor Math Bollen, Avd för energivetenskap, Institutionen för teknikvetenskap och matematik, Luleå tekniska universitet Tid: Måndag den 24 mars 2014, kl 09.00 Plats: Hörsal A, Campus Skellefteå, Luleå tekniska universitet
SmartGrid Energilager

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Rydman, Allan. "Sammanställning och fördjupning av begreppet Smarta elnät: En litteraturstudie." Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-90352.

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I dagsläget har världen en stadigt växande befolkning och där igenom en stadigt växande energiförbrukning. Med en växande energiförbrukning har det under de senaste åren uppenbarats diskussioner rörande samhällets hållbarhet och miljöpåverkan. Samtidigt sker det en kontinuerlig teknikutveckling och människan är mer beroende av konstant elförsörjning än någonsin tidigare. Teknologiska framsteg, tillsammans med önskan att sträva mot ett mer hållbart samhälle med hög elleveranssäkerhet, har mynnat ett begrepp kallat smarta elnät. Till följd av att elnätet involverar en stor bransch råder det delad mening över vad som utgör ett smart elnät. Detta har lett till uppkomsten av olika definitioner och modeller av konceptet. I syfte att skapa en övergripande uppfattning har en litteraturstudie utförts för att sammanställa de huvudsakliga områden som utgör det smarta elnätet. För att skapa denna överblick har ett förslag på en övergripande definition framtagits enligt följande: Ett smart elnät är nästa steg i elnätets fortgående utveckling som sker till följd av samhällets ökande förlitlighet på konstant elförsörjning och önskan att begränsa människans miljöpåverkan. Målet är att med hjälp av kostnadseffektiva tekniska lösningar, effektiv teknik och ekonomiska drivkrafter främja införandet av ytterligare förnyelsebar elproduktion, en ökad elanvändning och ett effektivare utnyttjande av elnätet – ett elnät med låga förluster, hög elkvalitet och leveranssäkerhet med elkunder som är mer medvetna och delaktiga i sin elförbrukning än förr. Utifrån denna definition kan man summera smarta elnät till att omfatta två huvudsakliga intressen för samhället – hållbarhet och en ökad leveranssäkerhet. I framtiden förväntas därför elnätet hantera vidare utbredning av förnyelsebar elproduktion och en ökad elanvändning. För att möta denna förväntan har det dels konstaterats att nätkapaciteten behöver öka. Det har visats att en ökad nätkapacitet kan nås genom både tekniska lösningar som energilagring och effektivare komponenter men också icke-tekniska lösningar som politiska drivkrafter och incitament för elkunder att sänka sin maxförbrukning och elförbrukning i överlag i form av efterfrågeflexibilitet. I dagsläget finns inga uppenbara incitament för detta och det anses att reformer på vissa delar av elmarknaden kommer att krävas för att främja utvecklingen mot ett hållbart smart elnät. Samtidigt förväntas elnätet förse kunder med högre elkvalitet och leveranssäkerhet. Dagens elnät utgörs av många långlivade och, i många fall, gamla komponenter och investeringar kommer att behöva göras i moderna skyddssystem och kommunikationsnätverk i sinom tid ifall man vill uppnå nya förväntningar. Därtill förväntas det smarta elnätet omfatta olika typer av kommunikationsnätverk inom skyddssystem, övervakning och mätning. Därför har också information rörande relevanta kommunikationsprotokoll, -medier och -nätverk summerats där olika egenskaper lämpar sig för olika tillämpningar.
Currently the world has a steadily growing population and therefore steadily growing need of energy. With a growing need of energy, discussions regarding society’s sustainability and environmental impact have risen. At the same time modern technology has resulted in society being more dependent on a constant power supply than ever before. Technological advances, together with the desire to become a more sustainable society with high availability of power, have yielded a concept known as the smart grid. Due to the power grid being a huge industry there’s a divided perception regarding what a smart grid constitutes. This has resulted in the appearance of different definitions and models of the concept. Therefore a literary study was done with the purpose of creating an overall perception of the main aspects of the smart grid. To create this overview a proposed definition has been developed that describes the smart grid as mainly sustainable and available. The smart grid is the next step of the power grid’s ongoing development in response to society’s increasing reliability of a constant power supply and the wish for decreasing man’s environmental impact. With cost efficient technical solutions, efficient technology and economic forces the goal is to promote introduction of additional renewable electricity production, increased electricity utilization and a more efficient use of the power grid – a power grid with low losses, high power quality and availability with end-users that are more aware and involved in their power consumption than before. Based on this definition the smart grid can be summarized as two main interests for society – sustainability and a higher reliability. In the future the power grid is expected to cope with an increased introduction of renewable electricity production and an increased use of electrical applications. It has been concluded that the grid capacity has to increase in order to meet these expectations. It’s been shown that an increase in grid capacity can be achieved through technical solutions as energy storage and more efficient electrical components but also through non-technical solutions as political forces and incentives for end-users to lower their peak consumption and overall electricity consumption through demand response. At present there are no clear incentives for this and it’s considered that there is a need for reform of certain parts of the electricity market to promote the development towards a sustainable smart grid. The power grid is also expected to supply end-users with a higher power quality and reliability. The power grid of today consists of long lived and, in many cases, old components and investments in modern protection systems and communication networks are required in due time to meet new expectations. In addition, the smart grid is expected to include different types of communication network within protection systems, monitoring and metering. Information was therefore summarized regarding relevant communication protocols, media and networks where different properties are suitable for different applications.

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Etherden, Nicholas. "Increasing the hosting capacity of distributed energy resources using storage and communication." Licentiate thesis, Luleå tekniska universitet, Energivetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18009.

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The use of electricity from Distributed Energy Resources like wind and solar powerwill impact the performance of the electricity network and this sets a limit to theamount of such renewables that can be connected. Investment in energy storage andcommunication technologies enables more renewables by operating the networkcloser to its limits. Electricity networks using such novel techniques are referred toas “Smart Grids”. Under favourable conditions the use of these techniques is analternative to traditional network planning like replacement of transformers orconstruction of new power line.The Hosting Capacity is an objective metric to determine the limit of an electricitynetwork to integrate new consumption or production. The goal is to create greatercomparability and transparency, thereby improving the factual base of discussionsbetween network operators and owners of Distributed Energy Resources on thequantity and type of generation that can be connected to a network. This thesisextends the Hosting Capacity method to the application of storage and curtailmentand develops additional metrics such as the Hosting Capacity Coefficient.The research shows how the different intermittency of renewables and consumptionaffect the Hosting Capacity. Several case studies using real production andconsumption measurements are presented. Focus is on how the permitted amountof renewables can be extended by means of storage, curtailment and advanceddistributed protection and control schemes.
Användningen av el från förnyelsebara energikällor som vind och sol kommer att påverka elnätet, som sätter en gräns för hur mycket distribuerad energiproduktion som kan anslutas. Investeringar i storskalig energilager och användning av modern kommunikationsteknologi gör det möjligt att öka andelen förnyelsebarenergi genom att nätet kan drivas närmare sina gränser. Elnät med sådana nya tekniker kallas ofta för ”Smarta Elnät". Implementering av sådana smarta elnät kan vara ett alternativ till traditionell nätplanering och åtgärder som utbyte av transformatorer eller konstruktion av nya kraftledningen.Nätets acceptansgräns är ett objektivt mått för att bestämma gränsen för nätets förmåga att integrera ny förbrukning eller produktion. Målet är att skapa större transparens och bidra till ett bättre faktaunderlag i diskussioner mellan nätoperatörer och ägare av distribuerade energiresurser. Denna avhandling utökar acceptansgränsmetoden för tillämpning med energilager och produktions nedstyrning och utvecklar ytterligare begrepp så som acceptansgränsen koefficienten.Forskningen visar hur varierbarheten hos olika förnyelsebara energikällor samverkar med förbrukningen och påverkar nätets acceptansgräns. Flera fallstudier från verkliga elnät och med uppmätt produktion och konsumtion presenteras. Fokus är på hur den tillåtna mängden förnyelsebara energikällor kan ökas med hjälp av energilagring, kontrollerad produktionsnedstyrning och med avancerad distribuerade skydd och kontroll applikationer.

Godkänd; 2012; Bibliografisk uppgift: Nicholas Etherden works at STRI AB (www.stri.se) in Gothenburg, Sweden. When he is not pursuing his half-time PhD studies he works as a specialist consultant in the field of Power Utility Automation, specialising on the IEC 61850 standard for power utility automation (today widely used in substations as well as some wind parks, hydro plants and DER and Smart Grid applications such as vehicle-to-grid integration). The author of this thesis received his Master of Science in Engineering Physics from Uppsala University 2000. Side tracks during his engineering studies included studies in theoretical philosophy, chemistry, ecology and environmental sciences as well as chairing the Swedish student committee of the Pugwash Conferences on Science and Worlds Affairs and later board member of the International Network of Engineers and of Scientists for Global Responsibility (INES) and chair of Swedish Scientists and Engineers Against Nuclear Arms. He has been a trainee at ABB in Västerås Sweden and spent six years as developer and team leader for the application development of a new relay protection family (ABB IED 670 series). In parallel to his professional work he studied power system engineering at Mälardalens University and travelled to all continents of the world. Since 2008 he is responsible for the STRI IEC 61850 Independent Interoperability Laboratory and a member of IEC Technical Committee 57 working group 10 "Power system communication and associated data models” and UCA/IEC 61850 User group testing subcommittee. He is co-author of IEC 61850-1 and main contributor to “Technical Report on Functional Test of IEC 61850 systems” and has held over 25 hands-on courses around the world on IEC 61850 “Communication networks and systems for power utility automation”.; 20120514 (niceth); LICENTIATSEMINARIUM Ämnesområde: Energiteknik/Energy Engineering Examinator: Professor Math Bollen, Institutionen för teknikvetenskap och matematik, Luleå tekniska universitet Diskutant: Professor Sami Repo, Tampere University of Technology, Finland Tid: Onsdag den 13 juni 2012 kl 10.00 Plats: Hörsal A, campus Skellefteå, Luleå tekniska universitet

SmartGrid Energilager

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Trovò, Andrea. "Industrializing Vanadium Redox Flow Battery." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3422708.

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Redox flow batteries (RFBs) have strong potential for providing future stationary energy storage, in view of the rapid expansion of renewable energy sources and smart grids. Their development and future success largely depend on the research on new materials mainly electrolytic solutions, membranes, and electrodes that are typically conduced on small single cells. Technological development plays a fundamental role in view of the successful application of RFBs in large plants, and while a quite vast literature on these topics already exists, very little research has been reported on the technology of large RFB systems. This thesis presents the design, construction, and extensive experimental campaigns of a vanadium redox flow battery (VRFB) test facility of industrial size, referred to as IS-VRFB, where such technologies have been developed and tested. The heart of the IS-VRFB is a 9 kW/27 kW h 40-cell 600 cm2 stack, which is one of the very few VRFB plants of this size in the world. The polarization curve during charge and discharge has been performed showing superior performances in comparison to those normally reported in the literature for this type of battery, and a procedure for qualifying such performance has been developed, and is presented in this study. Extensive numerical modeling has been carried out to gain a full understanding of the experimental data. Accordingly, this thesis reports on an original model capable of simulating the thermal behavior of a VRFB stack both in standby (i.e. without power and reactants flow), and in charge/discharge conditions, capable of computing the evolution of the temperature distribution in the cells (taking into account ions crossover through the membrane, and Joule loss due to shunt currents and inherent self-discharge effects). For the first time, a model is presented that is capable of simulating the cell temperature distribution in the stack and its time evolution considering all above effects, providing new results that can constitute the basis for advanced cooling strategies in future industrial RFB systems. An analysis is also presented of the losses occurring in the system due to species crossover, shunt current, hydraulic pressure drops, and pumping, in addition to cell over potentials. Fast response analyses have been developed, achieving important information with regard to the dynamic response of the battery when connected to a grid. Preliminary impedance spectroscopy tests in a multichannel configuration are also reported showing the electrical behavior of such a VRFB system. This study enables important drivelines to aid the designers of a compact VRFB stack to increase the battery efficiency. Similar analyses have been performed to obtain the optimal flow for each operating condition on such an industrial VRFB system. To the best of the autor's knowledge, studies that offer detailed scrutiny of all major loss causes that are experimentally validated on a kW-class system are missing in the literature. In general, the results presented are new and aim to cover the lack of studies on IS-VRFB in view of widespread commercialization.

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Bataglioli, Rodrigo Pavanello. "Proteção digital de geradores eólicos com conversores de potência de escala completa no contexto das smart grids." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18154/tde-25092018-155933/.

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Considerando condições anormais que o Sistema Elétrico de Potência (SEP) está sujeito, a proteção de seus elementos é um tópico importante. Dentre os equipamentos a serem protegidos, destacam-se os geradores devido a representarem elevado custo de investimento e estarem sujeitos a multas por paradas não programadas. Desta forma, com base em pesquisa bibliográfica, observa-se que não existem estudos abrangentes para a proteção individual de máquinas síncronas aplicadas à geração eólica. Além disso, considerando o contexto das smart grids, a presença de baterias e a possibilidade da operação ilhada podem alterar a dinâmica das situações de falta. Portanto, faz-se necessário um estudo do comportamento dos aerogeradores em situações de falha, sabendo que o esquema de proteção depende do tipo de gerador e da maneira como este está conectado ao SEP. Neste sentido, esta pesquisa propôs incluir uma bateria para operar com um gerador eólico de velocidade variável de forma complementar, suavizando a potência de saída e tornando o sistema de conversão de energia eólica forte o suficiente para operar no modo ilhado. A metodologia estabelece vários tipos de falhas para investigar o comportamento da turbina eólica em tais condições. Para realizar as simulações de falta, foi utilizado um simulador digital de tempo real (RTDS®). Com base nisso, um esquema composto por funções de proteção convencionais foi especificado e testado usando o software MATLAB®. Além disso, simulações em laço fechado foram realizadas com relés comercial e universal. Os resultados obtidos com o esquema proposto são bastante promissores.
Considering abnormal conditions to which the Electric Power System (EPS) may be subjected, the protection of its elements is an important topic. Among the equipments to be protected, the generators are highlighted, because they represent a high investment cost and are subjected to penalties for unscheduled stoppages. Hence, based on literature, it is observed that there are no comprehensive studies and standards for individual protection of Synchronous Generators (SGs) applied to Wind Energy Conversion System (WECS). Furthermore, considering the smart grids context, the presence of batteries and the possibility of island operation may change the dynamic of fault situations. Therefore, it is necessary to study and analyse the behavior of wind turbines in fault situations, knowing that the protection scheme is dependent on the generator type and the way it is connected to the EPS. In order to study these issues, this research proposed to include a battery to operate with a full-variable speed wind generator in a complementary way, smoothing the output power and making the WECS strong enough to operate in the island mode. The methodology establishes several fault types to investigate the wind turbine behavior in such conditions. In order to conduct the fault simulations, a real time digital simulator (RTDS®) was used. Based on this, a scheme composed by conventional protection functions were specified and tested using the MATLAB® software. Furthermore, hardware-in-the-loop simulations were performed with commercial and universal relays. Very good results in favor of the proposed scheme are presented.

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Beauchêne, Solène. "Le Smart Thermogène Grid ® : étude des potentiels de récupération, de stockage et de redistribution des énergies fatales et renouvelables, optimisation et gestion d’un système intelligent intégrant l’ensemble des énergies disponibles dans le bâtiment." Thesis, Ecole nationale des Mines d'Albi-Carmaux, 2016. http://www.theses.fr/2016EMAC0002/document.

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Le projet Smart Thermogène Grid® s’intègre dans la dynamique actuelle d’économie d’énergie en s’intéressant à la mise en œuvre de solutions de récupération et de stockage des énergies fatales et renouvelables dans le bâtiment résidentiel. L’objectif de ce travail de thèse est de proposer une approche globale permettant le choix et le dimensionnement de ces systèmes. Ce manque freine leur intégration au sein du bâtiment ainsi que l’évolution du bilan énergétique. Dans ce contexte, une modélisation de type « boites grises » qui se base sur un assemblage de modules (récupérations sur air extrait, sur eaux usées et solaire, stockages géothermique et en cuve) a été développée. Ce type de démarche permet une simplification importante du modèle complet et une réduction considérable du nombre de paramètres à déterminer. Il devient alors possible de mettre en place une méthode d’optimisation sous contrainte de type GPS afin d’aboutir à un dimensionnement physique. Une solution discrète est ensuite proposée grâce à une recherche dans des bases de données. Il est ainsi possible de répondre à la problématique et de proposer un dimensionnement cohérent du SThG®
The goal of the SThG® project is to recycle, to store and to manage unavoidable and renewable energies in the residential building. The aim of the work performed is to fill the lack of research on global sizing of systems, which is a barrier to the evolution of the energy balance of the building. Indeed, available tools are not adapted to make optimized choices and to size systems as they are very time-consuming. That is why an alternative model has been found. This work can be divided into two main steps. The first one, consists in doing a simplified model of a building and its systems. The second one in applying optimization to have the best choice and the better sizing of those systems according to energy and economic criterions. To solve this problem a model has been developed and two blocks can be identified. The first block is composed of two main points: the establishment of a physical model and the physical optimization. First, a macroscopic model of a building and its systems (recovery, storage and generation) has been created. This model is as much as generic as possible in order to represent a huge part of systems. But, it is also precise to ensure a good description of the real way they work and to allow the link to systems after the physical optimization during block two. Secondly, a Global Pattern Search optimization is used to find the best physical solution according to the constraints of the situation. The second block permits to find solutions in a discrete data basis of systems. These two blocks allow a durability of the tool, indeed the mechanism of optimization depends on the physical model. It will be possible to enrich the data basis of the second block without reconsidering the first one. Thanks to this work, a consistent choice and sizing of systems can be found

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Bonora, Giulia. "Analysis of the impact of stationary energy storage systems in trolleybus grids using Simulink-based modelling." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amslaurea.unibo.it/25832/.

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The voltage profile of the catenary between traction substations (TSSs) is affected by the trolleybus current intake and by its position with respect to the TSSs: the higher the current requested by the bus and the further the bus from the TSSs, the deeper the voltage drop. When the voltage drops below 500V, the trolleybus is forced to decrease its consumption by reducing its input current. This thesis deals with the analysis of the improvements that the installation of an BESS produces in the operation of a particularly loaded FS of the DC trolleybus network of the city of Bologna. The stationary BESS is charged by the TSSs during off-peak times and delivers the stored energy when the catenary is overloaded alleviating the load on the TSSs and reducing the voltage drops. Only IMC buses are considered in the prospect of a future disposal of all internal combustion engine vehicles. These trolleybuses cause deeper voltage drops because they absorb enough current to power their traction motor and recharge the on board battery. The control of the BESS aims to keep the catenary voltage within the admissible voltage range and makes sure that all physical limitations are met. A model of FS Marconi Trento Trieste is implemented in Simulink environment to simulate its daily operation and compare the behavior of the trolleybus network with and without BESS. From the simulation without BESS, the best location of the energy storage system is deduced, and the battery control is tuned. Furthermore, from the knowledge of the load curve and the battery control trans-characteristic, it is formulated a prediction of the voltage distribution at BESS connection point. The prediction is then compared with the simulation results to validate the Simulink model. The BESS allows to decrease the voltage drops along the catenary, the Joule losses and the current delivered by the TSSs, indicating that the BESS can be a solution to improve the operation of the trolleybus network.

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Alghamdi, Turki. "Interactions of Connected Electric Vehicles with Modern Power Grids in Smart Cities." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42513.

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In a smart city, it is vital to provide a clean and green environment by curbing air pollution and greenhouse gas emissions (GHGs) from transportation. As a recent action from many governments aiming to minimize transportation’s pollution upon the climate, new plans have been announced to ban cars with gas engines throughout the world. Therefore, it is anticipated that the presence of electric vehicles (EVs) will grow very fast globally. Consequently, the necessity to establish electric vehicle supply equipment (EVSE) in the smart city through public charging stations is growing incrementally year by year. However, the EV charging process via EVSE which is primarily connected to the power grid will put high pressure upon the centralized power grid, especially during peak demand periods. Increasing the power production of power grid will increase the environmental impact. Therefore, it is fundamental for the smart city to be equipped with a modern power grid to cope with the traditional power grid’s drawbacks. In this thesis, we conduct an in-depth analysis of the problem of EVs’ interaction with the modern power grid in a smart city to manage and control EV charging and discharging processes. We also present various approaches and mechanisms toward identifying and investigating these challenges and requirements to manage the power demand. We propose novel solutions, namely Decentralized-EVSE (D-EVSE), for EVs’ charging and discharging processes based on Renewable Energy Sources (RESs) and an energy storage system. We present two algorithms to manage the interaction between EVs and D-EVSE while maximizing EV drivers’ satisfaction in terms of reducing the waiting time for charging or discharging services and minimizing the stress placed on D-EVSE. We propose an optimization model based on Game Theory (GT) to manage the interaction between EVs and D-EVSE. We name this the decentralized-GT (D-GT) model. This model aims to ﬁnd the optimal solution for EVs and D-EVSE based on the concept of win-win. We design a decentralized proﬁt maximization algorithm to help D-EVSE take proﬁt from the electricity price variation during the day when selling or buying electricity respectively to EVs or from the grid or EVs as discharging processes. We implement different scenarios to these models and show through analytical and simulation results that our proposed models help to minimize the D-EVSE stress level, increase the D-EVSE sustainability, maximize the D-EVSE proﬁt, as well as maximize EV drivers’ satisfaction and reduce EVs’ waiting time.

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Lu, Di. "Conception et contrôle d’un générateur PV actif à stockage intégré : application à l’agrégation de producteurs-consommateurs dans le cadre d’un micro réseau intelligent urbain." Thesis, Ecole centrale de Lille, 2010. http://www.theses.fr/2010ECLI0021/document.

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L’intégration de panneaux photovoltaïques dans un système électrique réduit la consommation des sources fossiles et apporte des avantages environnementaux. Toutefois, l'intermittence et les fluctuations de puissance détériorent la qualité d’alimentation électrique. La solution proposée est d’ajouter des éléments de stockage, coordonnés par un contrôleur local qui gère les flux de puissance entre toutes les sources et la disponibilité énergétique. Ce générateur actif PV peut générer des références de puissance et fournir des services « système » au réseau électrique. Puis les concepts liés au micro réseau sont transposés pour concevoir un système central de gestion de l'énergie d'un réseau électrique résidentiel, qui est alimenté par des générateurs actifs PV et une micro turbine à gaz. Un réseau de communication est utilisé pour échanger des données et des références de puissance. Un système de gestion de l'énergie est développé avec différentes fonctions de contrôle sur des échelles de temps différentes afin de maximiser l'utilisation de l'énergie PV. Une planification opérationnelle quotidienne est conçue par un algorithme déterministe, qui utilise la prédiction d'énergie PV et de la charge. Puis ces références de puissance sont actualisées chaque demi-heure en tenant compte de la disponibilité de l’énergie PV et l’état des unités de stockage. Les erreurs de prévision et les incertitudes sont compensées par le réglage primaire de fréquence. Les résultats de simulation et les tests valident la conception de la commande du générateur actif photovoltaïque ainsi que le système central de gestion de l'énergie du réseau résidentiel étudié
The integration of PV power generation in a power system reduces fuel consumption and brings environmental benefits. However, the PV power intermittency and fluctuations deteriorate the power supply quality. A solution is proposed by adding energy storages, which are coordinated by a local controller that controls the power flow among all sources and implements an inner energy management. This PV based active generator can generate power references and can provide ancillary services in an electric network. Then micro grid concepts are derived to design a central energy management system of a residential network, which is powered by PV based active generators and a gas micro turbine. A communication network is used to exchange data and power references. An energy management system is developed with different time-scale functions to maximize the use of PV power. An operational daily planning is designed by a determinist algorithm, which uses 24 hour-ahead PV power prediction and load forecasting. Then power references are refreshed each half of an hour by considering the PV power availability and the states of energy storage units. Prediction errors and uncertainties are compensated by primary frequency controllers. Simulation and testing results validate the design of the PV active generator local controller and the central energy management system of the studied residential network

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Villavicencio, Manuel. "Analyzing the optimal development of electricity storage in electricity markets with high variable renewable energy shares." Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLED044/document.

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L’essor des technologies renouvelable à apport variable pose des nombreuses difficultés dans le fonctionnement du système électrique. Ce système doit garantir l’équilibre offre-demande à tout moment, ainsi que d’assurer des hauts niveaux de fiabilité du service. Donc, la variabilité accroît les besoins de flexibilité et des services système. Ils existent plusieurs options capables de fournir ceux services, dont : le renforcement des interconnections, le pilotage intelligent de la demande, le renforcement des capacités de réponse rapide des unités de production, mais aussi, le mis en œuvre des technologies de stockage de l’électricité. Cependant, les marchés électriques actuels sont basés sur la rémunération de l’énergie. Donc, la valorisation intégrale des services qui peut fournir le stockage semble difficile, ce qui restreint le « business case » des options de flexibilité.Cette thèse s’inscrit autour des propos suivants : (1) modéliser et évaluer les interrelations entre variabilité, besoins de flexibilité et objectifs de décarbonation du parc électrique, (2) analyser le rôle, ainsi que la valeur, des différents technologies du stockage à travers le cas Français aux horizons 2020, 2030 et 2050, et (3) discuter sur les aspects de régulation de la flexibilité, ainsi que proposer des politique énergétiques concrètes permettant la réussite des objectifs de transition énergétique et de décarbonation du mix électrique français
The increasing variability of electricity production in Europe, which is mainly due to the intermittent production of renewables such as wind and photovoltaic (VRE), will require significant efforts to reconcile demand and supply at all times. Thus, increasing shares of variability imply increasing amounts of system services. In addition to upgraded interconnections, demand-side management (DSM) and dispatchable backup capacity, electric energy storage (EES) technologies will have a major role to play in this context.However, due to the peculiar price formation mechanism prevailing in energy-only electricity markets, the commercial case for EES is being eroded by the very forces that create the need for its increased deployment at the system level. The private incentives of EES are thus diminishing while its social value, which is determined by the multiple system services these technologies can supply, is increasing.This thesis sets out to (1) model and assess the interplays between variability, flexibility needs and decarbonization objectives, (2) analyze the role and the value of EES technologies in view of the French official objectives by 2020, 2030 and 2050, and (3) discuss regulatory aspects, and propose a set of energy policies allowing to succeed in the energy transition and decarbonization goals

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de, Azevedo Ricardo. "Fully Decentralized Multi-Agent System for Optimal Microgrid Control." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/2461.

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In preparation for the influx of renewable energy sources that will be added to the electrical system, flexible and adaptable control schemes are necessary to accommodate the changing infrastructure. Microgrids have been gaining much attention as the main solution to the challenges of distributed and intermittent generation, but due to their low inertia, they need fast-acting control systems in order to maintain stability. Multi-Agent Systems have been proposed as dynamic control and communication frameworks. Decentralized arrangements of agents can provide resiliency and the much-desired “plug and play” behavior. This thesis describes a control system that implements droop control and the diffusion communication scheme without the need of a centralized controller to coordinate the Microgrid agents to maintain the frequency and stable operating conditions of the system. Moreover, the inter-agent communication is unaffected by changing network configurations and can achieve optimal economic dispatch through distributed optimization.

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Mondal, Abrez. "ANALYSIS AND MITIGATION OF FREQUENCY DISTURBANCES IN AN ISLANDED MICROGRID." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1492563068162654.

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MUSIO, MAURA. "Management and modelling of battery storage systems in microGrids and virtual power plants." Doctoral thesis, Università degli Studi di Cagliari, 2016. http://hdl.handle.net/11584/266749.

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In the novel smart grid configuration of power networks, Energy Storage Systems (ESSs) are emerging as one of the most effective and practical solutions to improve the stability, reliability and security of electricity power grids, especially in presence of high penetration of intermittent Renewable Energy Sources (RESs). This PhD dissertation proposes a number of approaches in order to deal with some typical issues of future active power systems, including optimal ESS sizing and modelling problems, power ows management strategies and minimisation of investment and operating costs. In particular, in the first part of the Thesis several algorithms and methodologies for the management of microgrids and Virtual Power Plants, integrating RES generators and battery ESSs, are proposed and analysed for four cases of study, aimed at highlighting the potentialities of integrating ESSs in different smart grid architectures. The management strategies here presented are specifically based on rule-based and optimal management approaches. The promising results obtained in the energy management of power systems have highlighted the importance of reliable component models in the implementation of the control strategies. In fact, the performance of the energy management approach is only as accurate as the data provided by models, batteries being the most challenging element in the presented cases of study. Therefore, in the second part of this Thesis, the issues in modelling battery technologies are addressed, particularly referring to Lithium-Iron Phosphate (LFP) and Sodium-Nickel Chloride (SNB) systems. In the first case, a simplified and unified model of lithium batteries is proposed for the accurate prediction of charging processes evolution in EV applications, based on the experimental tests on a 2.3 Ah LFP battery. Finally, a dynamic electrical modelling is presented for a high temperature Sodium-Nickel Chloride battery. The proposed modelling is developed from an extensive experimental testing and characterisation of a commercial 23.5 kWh SNB, and is validated using a measured current-voltage profile, triggering the whole battery operative range.

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Näslund, Katarina, and Andrea Stafverfeldt. "Energioptimering genom samverkan : en nulägesrapport av sektorkoppling i Sverige." Thesis, KTH, Energiteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-276420.

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För att Sverige ska uppnå de energimål som satts upp i enighet med Agenda 2030, är det av stor vikt att implementera mer förnybara resurser. Sektorkopplingsstrategier är en potentiell åtgärd vilket skulle optimera det svenska energisystemet. På sikt skulle det även kunna frigöra kapacitet, och därmed möjliggöra hantering av en större andel förnybara källor i elnätet. Syftet med den här studien är att bistå med en nulägesrapport av sektorkopplingsetablering i Sverige, med särskild fördjupning i region Gotland. Studien grundas i en omfattande litteraturstudie och kvalitativa intervjuer. Genom att studera tidigare litteratur inom området identifierades tekniker och metoder inom sektorkoppling, vars nuvarande utsträckning i Sverige kartlades. Den fördjupade datainsamlingen för studien var ostrukturerade kvalitativa intervjuer med projektledare och aktörer med relevans för Gotland. Resultatet från studien är en sammanställning av sektorkopplingtekniker samt hur dessa kan bidra till att öka flexibiliteten i energisystemet i allmänhet, och elnätet i synnerhet. Vidare kartlades projekt i Sverige som tillämpar dessa tekniker. Slutsatserna visar på att sektorkoppling redan är etablerat i Sverige, men befinner sig i ett tidigt stadium. Resultatet visade vidare att det krävs engagemang från kunder och aktörer, samt en viss standard i energisystemet för att möjliggöra en framgångsrik tillämpning av sektorkoppling i det svenska energisystemet. Resultaten belyser likväl att en fortsatt etablering av sektorkoppling kan komma att kräva ekonomiska incitament i form av bidrag och satsningar.
Including more renewable energy sources in the energy system is of great importance to enable Sweden to achieve its climate goals in unity of Agenda 2030. Sector coupling is a potential strategy for energy optimization, which in time could become a more established method to manage capacity issues, as well as permitting more renewable energy sources in the electricity grid. The purpose of this study is to compile a status report on current sector coupling in Sweden, with additional further investigation of region Gotland. The study is based on a comprehensive literature study as well as data collection through qualitative interviews with relevant stakeholders. Previous research and literature in the field enabled the identification of different technologies and methods relating to sector coupling. Qualitative data was gathered through unstructured interviews with represenatatives from companies and organizations having their focus set on energy planning in the Gotland region. The results consist of an assortment of various sector coupling technologies and their ability to increase the flexibility of the power grid and energy system in Sweden. In addition, several projects with diverse implementation of sector coupling strategies were also being mapped out. In conclusion, it became apparent that sector coupling is only at its earlier stages of implementation in Sweden. Further interest and commitment by customers and businesses is of great importance and needed to enable expansion of sector coupling technologies in Sweden. Moreover, the energy system requires standards, as well as financial incentives to promote further use of sector coupling in society.

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Mahmoud, Thair. "Optimal power generation in microgrids using agent-based technology." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2013. https://ro.ecu.edu.au/theses/599.

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The existing power grids that form the basis of the respective electrical power infrastructures for various states and nations around the world, are expected to undergo a period of rapid change in the near future. The key element driving this change is the emergence of the Smartgrid. The Smartgrid paradigm represents a transition towards an intelligent, digitally enhanced, two-way power delivery grid. The aim of the Smartgrid is to promote and enhance the e_cient management and operation of the power generation and delivery facilities, by incorporating advanced communications, information technology, automation, and control methodologies into the power grid proper. Smartgrid's are currently an active topic for research, where the research is strongly focused on developing new technologies such as: demand response, power generation management, pricing modelling and energy markets participation, power quality, and self-healing scenarios. In recent times, in both the United States of America and Europe, many new projects have begun which are specifically directed towards developing “Smartgrid” technologies. In Australia, the Federal Government has recently initiated funding plans to promote the commercialisation of renewable energy. In order to exploit these developments, Edith Cowan University (ECU); which is a High Voltage (HV) customer for the major utility network of Western Australia, and which owns its own transformers and Low Voltage (LV) network; is planning to integrate renewable energy suppliers within its LV network. The aim of this research is to introduce a smart decision making system, which can manage the operation of disparate power generation sources installed on a LV network (microgrid); such as that owned by ECU on its campuses. The proposed energy management system is to gather data in real-time, and it must be capable of anticipating and optimising energy needs for each operational scenario that the microgrid might be expected to experience. The system must take into account risk levels, while systematically favouring low economic and environmental costs. A management system application, based on autonomous and distributed controllers, is investigated in a virtual environment. The virtual environment being a full-scale simulation of ECU's microgrid; with solar panels, wind turbines, storage devices, gas gen-sets, and utility supply. Hence the simulation studies were conducted on the basis of realistic demand trends and weather conditions data. The major factors for reducing the cost of generation in the case study, were identified as being: 1) demand forecasting; 2) generation scheduling; 3) markets participation; and 4) autonomous strategies configuration, which is required to cope with the unpredictable operation scenarios in LV networks. Due to the high uncertainty inherent within the operational scenarios; an Artificial Intelligence (AI) deployment for managing the distributed sub-systems was identified as being an ideal mechanism for achieving the above mentioned objectives. Consequently it is proposed that Multi-Agent System (MAS) technology be deployed, to enable the system to respond dynamically to the unpredictable operational conditions by updating the method of analysis. The proposed system is to behave in a strategic manner when dealing with the expected operational scenarios, by aiming to achieve the lowest possible cost of power generation for the microgrid. The simulated system is based on realistic operational scenarios, which have been scaled to suit the size and type of load in the case study. The distributed intelligent modules have proven to be successful in achieving the potential benefits of the dynamic operational conditions, by minimising the cost of power generation. The distributed intelligent modules, which form the basis of the proposed management systems, have been designed to perform the following functions: 1. Provide accurate demand forecasts through the utilisation of an AI-based adaptive demand forecasting model. The novel demand-forecast modelling technique, which was introduced to model demand in the case study, has been utilised to supply reasonably accurate demand forecasts to other stages of processing in the management system. The forecasts are generated from this model, by monitoring and controlling the forecasting error to ensure consistent and satisfactory forecasts. 2. Make optimum decisions concerning the operation of the power generators by considering the economic and the environmental costs. In order to deal with the complexity of the operational conditions, a smart and adaptive generation scheduling method was implemented for the case study. The method was primarily applied to control the charging/ discharging process of the Storage Devices (SDs) among the other generators. The proposed method aims at controlling the resources, and extracting the benefit of having an hourly based variable generation cost. 3. Integrate the microgrid into the electricity market, in order to enable the microgrid to offer its spinning and non-spinning power generation reserve as Ancillary Services (AS) to the grid. To this end, studying the operational mechanisms of the Australian market was essential prior to building the proposed market participation rules which form an integral part of the proposed management system. As a result we used the market data, by approaching the market operators to create a semi-realistic competitive market environment for our simulations. Consequently, a smart and adaptive pricing mechanism, that adapts the AS prices to the amount of electricity on offer, and the level of demand in the market has been presented. The motivation for introducing the proposed management system, is to achieve a transition plan for current microgrids, so that they can have a commercial connection to the future Smartgrid. The results obtained in this work show that there is a signi_cant economic and environmental advantage to be gained from utilising intelligence when managing electricity generation within a power grid. As a consequence, selecting the appropriate management strategy is fundamental to the success of the proposed management system. In conclusion, modelling of the proposed strategies using MAS technology has proven to be a successful approach, and one that is able to reflect the human attitude; in making critical decisions and in reducing the cost of generation.

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Федорчук, Станіслав Олегович. "Забезпечення заявлених графіків генерації відновлюваних джерел енергії на основі концепції віртуальних електричних станцій." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/42333.

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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.14.02 - електричні станції, мережі і системи. – Національний технічний університет «Харківський політехнічний інститут», Харків, 2019. Дисертаційна робота присвячена розв’язанню актуальної науково-прикладної задачі у напрямку забезпечення заявлених графіків генерації електричних станцій на відновлюваних джерелах енергії на основі концепції віртуальних електричних станцій. У дисертаційній роботі досліджено методи забезпечення заявлених графіків генерації електричних станцій на ВДЕ та обґрунтована доцільність використання концепції віртуальних електричних станцій для вирішення поставленої задачі. Досліджено застосування різних типів систем акумуляції, як одного з елементів віртуальної електричної станції. Проведено аналіз існуючих методів впровадження інтелектуальних мереж, що дозволило вибрати шаблон Smart Grid Architecture Model за основу для створення необхідної інфраструктури. Проведено аналіз існуючих методів визначення оптимальної ємності систем акумуляції та їх компоновки. Розроблено комп‘ютерну модель для дослідження роботи віртуальних електричних станцій, що дозволяє оцінити потенційні небаланси при генерації, перевірити достатність обсягу систем акумуляції для різних задач, а також провести апробацію роботи системи управління. Уточнено методику розрахунку вартості електричної енергії від систем акумулювання з урахуванням вартості втрат енергії при передачі та трансформації, а також додаткових факторів пов‘язаних з орендою та обслуговуванням. Розроблено, реалізовано та апробовано алгоритм управління віртуальною електричною станцією, що базується на задіянні найбільш дешевого джерела енергії для балансування з урахуванням обмежень електричних мереж, доступу до енергетичного ринку та можливості залучення активних споживачів. Показана можливість забезпечення заявлених графіків генерації електричних станцій на основі концепції віртуальних електричних станцій на прикладі умов одного з адміністративних центрів України.
Dissertation for the degree of candidate of technical sciences in specialty 05.14.02 - power plants, networks and systems. - National Technical University "Kharkiv Polytechnic Institute", Kharkiv, 2019. The thesis is devoted to the solution of the current scientific and applied problem in the field of providing the declared schedules of generating power plants with renewable energy sources based on the concept of virtual power plants. In the dissertation work, the methods of providing the declared schedules of generating power plants on renewable energy sources are investigated. The expediency of using the concept of virtual power plants to solve the problem is justified. The use of various types of accumulation systems as one of the elements of a virtual power plant is investigated. The analysis of existing methods and state-of-the-art-practices of implementing intelligent networks was carried out, which made it possible to select the Smart Grid Architecture Model pattern as the basis for creating the necessary infrastructure. The analysis of existing methods for determining the optimal capacity of accumulation systems and their layout has been carried out that was used to calculate minimal capacity for providing the declared schedules of generation of PV and wind power plant each 1 MW for one of the administrative centers of Ukraine. The developed computer model for studying the operation of virtual power plants that include PV and wind power with energy storage and connections to PLC allows assessing potential unbalances during generation, checking the sufficiency of the capacity of accumulation systems for various tasks, as well as testing the operation of the control system. The methodology for calculating the cost of electrical energy from storage systems has been refined, taking into account the cost of energy losses during transmission and transformation, as well as additional factors associated with renting and servicing. An algorithm for managing a virtual power plant was developed, implemented and tested with real PLC connected to mathematical model, based on using the cheapest energy source for balancing taking into account the limitations of electrical networks, power lines and transforming equipment, access to the energy market for buying and selling energy and the ability to attract active consumers. The possibility of providing the declared schedules of generation of power plants based on the concept of virtual power plants on the example of conditions of one of the administrative centers of Ukraine is shown.

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Dissertations / Theses on the topic 'Energy Storage, Smart Grid'

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