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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
361

Laststyrning av elvärmesystem i småhus i ett lokalt elnät med effekttaxa : Beräkning av ekonomiska konsekvenser för nätägaren och en utblick mot sårbarheter i smarta elnät

Rosenkvist, Mari January 2021 (has links)
Smarta elnät nämns ofta som ett sätt att hantera ökad elektrifiering av transporter och industri och en växande andel väderberoende elproduktion. Ett syfte med det här examensarbetet är att studera möjliga följder för lokalnätägaren Sala-Heby Energi Elnät AB, om småhuskunder använder smart styrning av elvärmesystem för att sänka sina elnätsfakturor. Med rådande tariffmodell betalar småhusägaren för den gångna månadens tre högsta timmedeleffekter kl. 07 till 19 helgfria vardagar. Hur nätägaren påverkas av styrning, är en central fråga för projektet Auto-Flex, som startade i januari 2021. Uppsatsens litteraturstudie pekar på att efterfrågeflexibilitet kan ge olika följder för elnätet och för elmarknadens parter, beroende på vilka incitament som används för att skapa ett flexibelt beteende. Med efterfrågeflexibilitet avses här kunders förmåga att flytta eller minska sitt lastuttag från elnätet. I det här examensarbetet utförs beräkningar i Excel för att undersöka följderna av laststyrning och analysen utgår från historiska elmätardata från ca 140 anonymiserade hushållskunder samt från data över effektuttag från regionnätet. Beräkningarna visar att styrning som gynnar kunden ekonomiskt blir en förlustaffärför Sala-Heby Energi Elnät AB, trots sänkt effektuttag från regionnätet. Det gäller, i de flesta fall, även när extra styrning läggs till under timmar då effektuttaget från regionnätet är högt. Resultaten bygger på förenklade beräkningar, där ingen hänsyn tagits till hur effektsänkning av elvärmesystem samspelar med väderfaktorer eller med styrningens varaktighet. Samma effektsänkning har antagits vid varje styrtillfälle och för alla hushåll. Ett andra syfte med det här examensarbetet är att undersöka hur huvudaktörerna i projektet Auto-Flex ser på säkerhetsfrågor i samband utvecklingen mot ett mer IT-beroende elnät. Därför genomfördes två semistrukturerade intervjuer, med integritet, leveranssäkerhet och affärsmodeller som teman. Intervjupersonerna lyfte inga allvarliga hot kopplade till projektet Auto-Flex. Samtidigt kunde de se teoretiska risker med storskalig smart laststyrning i kapacitetssvaga elnät. Mer forskning behövs om smarta elnät och hållbarhet. Kopplingen mellan incitament till flexibilitet och flexibilitetens inverkan på elnätet, hur sårbarheter kopplade till informationsteknik påverkar elnätets leveranssäkerhet och hur smartteknik står sig miljömässigt i förhållande till nätutbyggnad är tre intressanta områden. / By facilitating demand side management, smart grids are expected to smooth the way for a transition to cleaner electric energy. This bachelor’s thesis aims to analyse the consequences for a distribution system operator (DSO) of direct load control,which is set to minimize the consumer’s bill for power transmission. This is also a central theme in the recently initiated Auto-Flex smart grid project, with main actors DSO Sala-Heby Energi Elnät AB and tech company Ngenic AB. The included study of scientific articles points out that the impact of demand response on electric grids is largely determined by incentives used to harvest demand side flexibility. In this thesis, the consequences of direct load control are examined by means of simplified calculations in Excel, analysing electric meter data from approximately 140 anonymous customers, in addition to power supply data for the township connection to the regional distribution grid. If customers with electric heating systems would install load control equipment to lower their power transmission bills, the local DSO would experience reduced revenues. The reduction in revenues would not be offset economically by curbed peak power transmission from the regional grid, according to the executed calculations. Even if extra load control was added in peak days, the net economic result for the local DSO would still be negative in most of the studied cases. Individual characteristics of heating systems and buildings have not been accounted for in this study, neither has the correlation between load reduction, outdoor temperature and load control duration. A second aim of this thesis is to examine attitudes of the main actors in the Auto-Flex project on confidentiality, reliability and demand side management business models in relation to the development of smart grids. Through semi-structured interviews, it was revealed that neither chief executive officer of Ngenic AB, Björn Berg, nor chief grid officer of Sala-Heby Energi Elnät AB, Per-Erik Johansson, see any severe threats against customer confidentiality, nor against power reliability, when implementing direct load control within the project. However, it was pointed out that an electric grid with very low physical capacity could become vulnerable to load control failures. Further examination of the connection between business models, power reliability, and cyber security are crucial to ensure socially, economically, and environmentally sustainable smart grids.
362

BPL modem / BPL modem

Chromý, David January 2020 (has links)
This work deals with the issue of PLC with a focus on BPL technology (Broadbandover-power lines), which is explained in the theoretical part. The work describes in detailthe main components for PCB design with manufacturing and mounting process. Fur-thermore, the thesis provides instructions on how to establish communication betweenBPL modems and a description of individual functions. In conclusion, the procedureof measuring the noise intensity in the 230 V power line is described with the results.The output of the diploma thesis is the selection of components and the implementationof printed circuit boards for two BPL modems. These modems allow to measure SNR(signal to noise ratio) at physical speed.
363

Spolupráce mikro zdrojů v rámci malé smart grid / Cooperation of micro sources within small smart grid

Cabala, Ľuboš January 2013 (has links)
This thesis concerns with design of micro sources and their implementation in Micro grid system. In the first part the work is aimed at definition of smart - grid, where describes their advantages, disadvantages and necessary changes, which has to be made in current distribution network for implementation this system. Further on the thesis concerns with detailed description of Micro grid, configuration of this kind of network, the issues in implementation and possibilities to provide ancillary services. The work also describes marginally virtual power plants, presents definition, components and types of virtual power plants. The final chapter describes the creation of micro sources in System modeler and subsequent testing of consumption cover to operate in island mode.
364

Réseau électrique intelligent pour les nouveaux usages / Smart grid for new uses

Duverger, Emilien 09 July 2019 (has links)
Avec la mutation du paysage énergétique due au développement des énergies renouvelables, des véhicules électriques ou encore des systèmes de stockage, le réseau électrique actuel a besoin de se moderniser. Le concept de microgrid est une solution prometteuse basée sur les technologies de l'information et de la communication pour améliorer la gestion et l'efficacité de la production, du transport, de la distribution et de la consommation de l'électricité. Cependant, les défis technico-économiques associés à leur déploiement sont encore élevés. Ces travaux de thèse ont pour but d’apporter des contributions sur plusieurs points clés : prévision de la production et de la consommation, modélisation des équipements, et optimisation de la gestion du microgrid.Rivesaltes-grid est un démonstrateur de microgrid à l'échelle d'un bâtiment industriel composé d'un champ photovoltaïque de 60 kWc, de batteries lithium-ion de 85 kWh et d'un véhicule électrique. Il a permis de développer un système de gestion de l'énergie (EMS) innovant pour optimiser l'efficacité énergétique du microgrid. Cet EMS, basé sur une gestion par commande prédictive et la résolution d'un problème d'optimisation avec contraintes, permet de réduire de 6,2% le coût de fonctionnement. Cette gestion du microgrid nécessite comme entrées : (1) la prévision de production basée sur un algorithme de forêt aléatoire et une modélisation du champ PV par modèle 1-diode, (2) la prévision de la consommation à partir de l'algorithme de partitionnement k-means++ et (3) la modélisation dynamique du système de stockage avec ses contraintes. / With the transformation of the energy landscape due to the development of renewable energies, electric vehicles and storage systems, the current grid needs to be modernized. Microgrid concept is a promising solution based on information and communication technologies to improve the management and efficiency of electricity generation, transmission, distribution and consumption. However, the technical and economic challenges associated with their deployment are numerous. The thesis aims to provide contributions on several key points: production and consumption forecasting, equipment modeling, and microgrid management optimization.Rivesaltes-grid is a microgrid demonstrator on the scale of an industrial building consisting of 60 kWp photovoltaic array, 85 kWh lithium-ion batteries and an electric vehicle. It has enabled the development of an innovative energy management system (EMS) to optimize the microgrids energy efficiency. This EMS, based on predictive control management and the resolution of a constrained optimization problem, reduces operation cost by 6.2%. This microgrid management requires as input: (1) the production prediction based on a random forest algorithm and a modeling of the PV field by 1-diode model, (2) the consumption prediction from partitioning algorithm k-means++ and (3) dynamic modeling of the storage system with its constraints.
365

Scope of BlockChain Technology in Energy Sector.

Khan, Muhammad Shoaib Arshad January 2019 (has links)
World energy systems are going through a continuous change. The focus has been shifted from large thermal or hydal power generation to small distributed generation, mainly based upon renewable energy systems. This transition is also backed by some governments. There have also been significant improvements in grid technology, and modern-day smart grid can provide real time bi-directional flow of data i.e. “real time energy deficit and surplus, and also real time prices to both producers and consumers. Smart grid can also accommodate intermittent small suppliers of electricity. This shift in energy generation policy and improvement in grid technology has opened ways for small scale energy producers and consumers to share energy with each other. It has also opened ways to purchase or sale energy to unknown peers over a smart grid. Need has been felt to store these transactions among peers in a secure, non-alterable yet quickly accessible way. Blockchain technology offers to provide this secure, unalterable yet quickly accessible ledger. In this study this transition process and role of blockchain technology for future energy systems has been historically reviewed. It has been found out that on top of keeping record of Peer to Peer transactions, blockchain technology can fill many other purposes. However, technology is still not matured for large scale projects, Research projects are underway to decrease the large time and energy consumption for block building computational processes yet keeping them safe and reliable.
366

Smart Grids and Turkey: An Overview of the Current Power System and Smart Grid Development

Keskin, Müge January 2021 (has links)
Successful integration of the smart grids is crucial for ensuring the efficiency, resiliency, and sustainability of future power systems. With a 46.53% increase in total primary energy supply between 2008 and 2018 (IEA, 2020a), Turkey has the fastest-growing energy market within OECD countries (Erdin and Ozkaya, 2019).Though, Turkey’s current electrical grid faces many challenges; such as high loss rates from the transmission and distribution lines (Damar, 2016; Düzgün, 2018; IBRD/The World Bank, 2016; TEİAŞ, 2019), frequent power outages (Guner and Ozdemir, 2011; Öztürk, 2017; Yanılmaz, 2016) and several incidents of large-scale blackouts (OECD/IEA, 2016; Project Group Turkey, 2015). Smart grid technologies can address Turkey’s power system’s challenges with a holistic approach, as the smart grid does not have a strict definition yet but has distinctive characteristics. This paper provides an overview of Turkey’s current electric power system’s challenges while analyzing Turkey’s progress up to the present day towards the smart grid transition. Also, in order to summarize fundamental smart grid technologies globally, a smart grid framework was designed. Founded upon the framework; Turkey’s previous actions for its power system development were assessed from the smart grid perspective, and further steps were proposed to accomplish a successful smart grid transition. Country-specific remarks regarding the electrical grid were highlighted, such as the risk of terrorism, high seismic activity in the region, and emerging nuclear power in the country. As a result, it is concluded that Turkey has initiated the process towards the smart grid transition not only to achieve a “smart grid ideal” but mainly to meet its growing energy demands. Furthermore, it is also concluded that if the smart grid technologies’ scope could be extended throughout the country, Turkey would overcome the challenges with its power system in short to medium-term.
367

Temporary Variables for Predicting Electricity Consumption Through Data Mining

Silva, Jesús, Senior Naveda, Alexa, Hernández Palma, Hugo, Niebles Núẽz, William, Niebles Núẽz, Leonardo 07 January 2020 (has links)
In the new global and local scenario, the advent of intelligent distribution networks or Smart Grids allows real-time collection of data on the operating status of the electricity grid. Based on this availability of data, it is feasible and convenient to predict consumption in the short term, from a few hours to a week. The hypothesis of the study is that the method used to present time variables to a prediction system of electricity consumption affects the results.
368

Performance Indicators for Smart Grids : An analysis of indicators that measure and evaluate smart grids

Busuladzic, Ishak, Tjäder, Marcus January 2020 (has links)
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.
369

Analysis of Demand-Response Participation Strategies for Congestion Management in an Island Distribution Network

Ryckebusch, Gaëlle January 2015 (has links)
The Master Thesis is part of the Smart Grid Gotlandproject. This project aims at implementing smart grid solutionson the island of Gotland in order to be able to efficientlyintegrate large quantities of renewable energy production.In situations of high wind power production and lowconsumption, energy export problems may occur betweenGotland and the mainland. A novel approach to manageanticipated congestions, compared to traditional gridreinforcements, consists of using flexibility from demandresponse(DR) resources. However, such an approach presentschallenges as it requires both technical and economic considerations.This Master Thesis proposes and analyses twomarket-based strategies applied to detached houses for dayaheadcongestion management. The strategies are implementedin an Ancillary Service toolbox developed in theMATLAB programming environment.The first strategy involves using a dynamic network tariffwhile the second uses spot price optimization. Simulationsare performed for seasonal worst-case congestion scenarioswhile satisfying comfort and economic constraints ofthe DR participants. A sensitivity analysis is carried out toassess the impact of different spot price profiles and windpower production prognosis errors on the results.Results show that congestions are managed with a feasiblenumber of participants, but that their savings are negligiblefor both strategies (between 2 and 40 SEK/participant).Moreover, using a dynamic network tariff strategy impliesa DSO cost in the range of 1700-89000 SEK. These resultsapply for a 3-days congestion period, which is estimated tooccur 5-6 times a year if the maximum hosting capacity isincreased by 5 MW.To conclude, an AS toolbox with economic constraintsis feasible for Gotland conditions with a reasonable numberof DR participants. However, the simple cost-benefitanalysis that was carried out showed that the AS toolboxapproach was still much more costly than traditional gridreinforcement.
370

Analysis of Demand Response Solutions for Congestion Management in Distribution Networks

Brodén, Daniel January 2013 (has links)
According to the 20-20-20 targets set by the European Union, 50 percent of the Swedish electricity share is to be provided by renewable energy sources by 2020. The Smart Grid Gotland (SGG) project has emerged as a response to this target. The project aims at demonstrating a proof of concept on how smart grid solutions can be used to integrate large quantities of renewable energy sources in an existing network. The outcomes of the project are intended to pave the way for future renewable energy integration projects in Sweden. The Thesis focuses on one of the technical objectives of the SGG project, i.e. to increase the hosting capacity of wind power on Gotland from 195 MW to 200 MW by using Demand-Response (DR) from households and industries. DR consist of shifting peak-loads to peakproduction hours. The integration of additional wind power causes a risk of exceeding the transmission capacity of the power export cable between Gotland and the Swedish mainland. The approach considered for this Thesis is to use an Ancillary Service (AS) toolbox scheme based on multi-agent systems. The AS toolbox consist of flexibility tools such as DR on long-term, short-term, a battery energy storage system and a wind curtailment scheme. The DR activity includes space heating and domestic hot water consumption from detached houses on Gotland. The simulation results indicate that 1900 household participants are sufficient to balance the additional 5 MW for worst case scenarios. Furthermore, it is shown that the DR participation from industries contributes in some cases to a reduction of 700 household participants. The findings helped conclude that using an AS toolbox solution on Gotland is fully possible from a technical perspective. However, barriers that stand against its realisation are of economical nature and need to be investigated in future studies.

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