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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.
101

Resposta da demanda no planejamento para integração de recursos energéticos distribuídos /

Moreira, Saulo Gomes January 2017 (has links)
Orientador: Dionízio Paschoareli Júnior / Resumo: No planejamento da integração de fontes de geração distribuída no sistema de distribuição em baixa tensão é fundamental que haja a investigação dos efeitos provocados nas condições operacionais da rede, tais como níveis de tensão e carregamento de transformadores. Com vista ao potencial aumento da geração fotovoltaica no cenário brasileiro e à iminente migração tecnológica das redes tradicionais para as chamadas redes inteligentes, a resposta da demanda se apresenta como uma das estratégias para possibilitar uma integração eficiente de recursos energéticos distribuídos. Na aplicação de um programa de resposta da demanda, especificamente para o cenário de uma distribuidora, permitiu-se concluir, através da utilização de dados reais, que no processo de planejamento de integração de novas fontes de geração de natureza fotovoltaica, a aplicação de uma estrutura tarifária com custos diferenciados horários baseados no custo marginal de capacidade do sistema, possibilita que sejam observadas melhores condições operacionais da rede. A aplicação da nova estrutura tarifária horária indica uma significativa alteração no perfil de carga esperado dos consumidores de baixa tensão o que refletiu em melhores valores de níveis de tensão e aumento da capacidade livre do transformador em integrar novas fontes distribuídas no sistema. / Abstract: In planning the integration of distributed generation sources in the low voltage distribution system, it is essential to investigate the effects caused by the network operating conditions, such as voltage levels and transformer loading. By the point of view of the potential increase in photovoltaic generation for the Brazilian scenario and the imminent technological migration of traditional networks to the so-called Smart Grids, demand response is one of the strategies to enable the efficient integration of distributed energy resources. By applying a demand response program, specifically for the scenario of a distribution company, it was possible to conclude, by using real data, that in the integration planning process of new photovoltaic based generation sources, the application of a tariff structure with hourly differentiated costs based on the system's marginal cost of capacity, allows better operational conditions of the network to be observed. The application of the new hourly tariff structure indicates a significant change in the expected load profile of the low voltage consumers, which reflected in better values of voltage levels and rising of the free capacity of the transformer to integrate new distributed sources into the system. / Doutor
102

[en] INCLUSION OF STATISTICAL METHODS AS BILLING SUPPORT OF SMART METERS / [pt] INCLUSÃO DE MÉTODOS ESTATÍSTICOS COMO APOIO AO FATURAMENTO DE ENERGIA REALIZADO POR MEDIDORES INTELIGENTES

WEULES FERNANDES CORREIA 03 October 2018 (has links)
[pt] A sociedade está vivendo em uma época de forte convergência tecnológica, onde novas tecnologias são descobertas e extintas em um prazo cada vez menor. Esta revolução tecnológica também já chegou para o setor de infraestrutura de distribuição de energia que são as Redes Elétricas Inteligentes, sendo o medidor inteligente o principal equipamento desta revolução. Apesar da evolução do parque de medidores brasileiros, a regulação comercial não acompanhou esta modernização e continua tendo como referência o sistema de medição convencional com a atuação de leituristas e não considerando as oportunidades de usar dados de consumo, mesmo que não sejam da data do faturamento nos casos de falhas de transmissão da informação e aplicação de ferramentas estatísticas para estimação no faturamento. Neste contexto, esta dissertação tem como objetivo avaliar as regras regulatórias de faturamento considerando as ausências de leituras, propor uma nova metodologia para definir como realizar o faturamento na ausência de leituras considerando consumos anteriores e usar ferramentas estatísticas para a definição do valor a ser faturado. A metodologia pode ser dividida em duas fases: (i) imputação de dados faltantes na base de dados decorrentes de possíveis erros de transmissão dos medidores; (ii) previsão do consumo de energia elétrica por cliente. O presente trabalho cumpriu os objetivos aos quais se propôs e apresentou uma alternativa promissora para o faturamento com medidores inteligentes e que utilize tecnologias de comunicação de baixo custo e que possam apresentar uma efetividade de medição abaixo da ideal, no caso, 100 por cento. / [en] Society is living in a time of strong technological convergence, where new technologies are discovered and extinguished in an ever shorter time frame. This technological revolution has also arrived for the energy distribution infrastructure with the Smart Grid, in which the smart meter being the main equipment of this revolution. Despite the evolution of the Brazilian meter park, the commercial regulation did not go along with this modernization and continues with reference to the conventional metering system and not considering the opportunities to use consumption data comes from out of the billing date, in cases of data transmission failures, being thus possible use statistical tools for billing estimation. In this context, this dissertation aims to evaluate the regulatory rules of billing considering the absences of readings, proposing a new methodology to define how to estimate the billing in the absence of readings, considering previous consumption and using statistical tools to define the value to be billed. The methodology can be divided into two phases: (i) imputation of missing data in the database, resulting from possible transmission errors of the meters; (ii) forecast of electricity consumption per customer. The present work fulfilled the objectives proposed and presented a promising alternative for billing with smart meters using low cost communication technologies that could have low measurement effectiveness, in this case, 100 percent.
103

Desenvolvimento de um sistema para aquisição e processamento de sinais utilizando a plataforma TivaWareTM para aplicações em Smart Grid

Lima, Alison Lins de 29 July 2015 (has links)
Submitted by Viviane Lima da Cunha (viviane@biblioteca.ufpb.br) on 2015-11-24T11:18:29Z No. of bitstreams: 1 arquivototal.pdf: 5459157 bytes, checksum: e363929cf9a6a71b88515b8a24c12af6 (MD5) / Made available in DSpace on 2015-11-24T11:18:29Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 5459157 bytes, checksum: e363929cf9a6a71b88515b8a24c12af6 (MD5) Previous issue date: 2015-07-29 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Amid a scenario, that contrasts the increasing demand for electricity, and decreased ability to generation from conventional sources, which is creating serious problems for the energy sector, the concept of smart grids popularizes up and presented as an alternative to, among other possibilities, minimize the effects of power outages in the design of distributed generation from alternative sources. In order for alternatives to that end, it will develop a data acquisition system, low cost and high performance for applications in smart grids, which facilitates monitoring of electricity in real time, where the user can manage their own control avoiding waste and consequently saving. The system will be developed based on the standards of ANEEL (Brazilian Electricity Regulatory Agency), body responsible for determining the minimum parameters a measuring equipment must possess. The data acquisition system showed results with a high degree of agreement when compared with the reference instrument, the fluke 434/435. A response curve of voltage and current, showing the system behavior compared to other instruments of measurement was introduced. Still, it is objective of the work that the signs Conditioning Unit can be adapted for multiple microprocessor platforms, using simple settings, without the need for hardware reconfiguration. This fact has been proven to be used with Black BeagleBone with satisfactory results. / Em meio a um cenário que contrasta o aumento da demanda por energia elétrica, e a diminuição da capacidade de geração a partir das fontes convencionais, o que vem gerando sérios problemas para o setor energético, o conceito de smart grids populariza-se e apresenta-se como uma alternativa para, entre outras possibilidades, minimizar os efeitos da falta de energia elétrica, na concepção de geração distribuída a partir de fontes alternativas. Com vistas em alternativas com esse fim, será desenvolvido um sistema de aquisição de dados, de baixo custo e alto desempenho, para aplicações em smart grids, que viabilize o monitoramento da energia elétrica em tempo real, onde o usuário possa gerir o seu próprio controle evitando o desperdício e, consequentemente, economizando. O sistema será desenvolvido com base nas normas da ANEEL (Agência Nacional de Energia Elétrica), órgão responsável por determinar os parâmetros mínimos que um equipamento de medição deve possuir. O sistema de aquisição de dados apresentou resultados com alto grau de concordância ao ser comparados com o instrumento de referência, o fluke 434/435. Foi apresentado uma curva resposta da tensão e corrente, mostrando o comportamento do sistema em comparação a de outros instrumentos de medições. Ainda, é objetivo do trabalho que a Unidade de Condicionamento dos Sinais, possa ser adaptada para múltiplas plataformas microprocessadas, através de simples ajustes, sem a necessidade de reconfiguração de hardware. Esse fato foi comprovado ao ser utilizada com a BeagleBone Black, apresentando resultados satisfatórios.
104

Resposta da demanda no planejamento para integração de recursos energéticos distribuídos / Demand response on the planning for distributed energy resources integration

Moreira, Saulo Gomes [UNESP] 02 June 2017 (has links)
Submitted by SAULO GOMES MOREIRA null (saulo.moreira@ufms.br) on 2017-07-10T19:51:39Z No. of bitstreams: 1 Tese - Saulo Gomes Moreira - versão final.pdf: 2776138 bytes, checksum: 0b13189e5f5b94bb917bb0912bd62b0f (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-07-13T20:43:59Z (GMT) No. of bitstreams: 1 moreira_sg_dr_ilha.pdf: 2776138 bytes, checksum: 0b13189e5f5b94bb917bb0912bd62b0f (MD5) / Made available in DSpace on 2017-07-13T20:43:59Z (GMT). No. of bitstreams: 1 moreira_sg_dr_ilha.pdf: 2776138 bytes, checksum: 0b13189e5f5b94bb917bb0912bd62b0f (MD5) Previous issue date: 2017-06-02 / No planejamento da integração de fontes de geração distribuída no sistema de distribuição em baixa tensão é fundamental que haja a investigação dos efeitos provocados nas condições operacionais da rede, tais como níveis de tensão e carregamento de transformadores. Com vista ao potencial aumento da geração fotovoltaica no cenário brasileiro e à iminente migração tecnológica das redes tradicionais para as chamadas redes inteligentes, a resposta da demanda se apresenta como uma das estratégias para possibilitar uma integração eficiente de recursos energéticos distribuídos. Na aplicação de um programa de resposta da demanda, especificamente para o cenário de uma distribuidora, permitiu-se concluir, através da utilização de dados reais, que no processo de planejamento de integração de novas fontes de geração de natureza fotovoltaica, a aplicação de uma estrutura tarifária com custos diferenciados horários baseados no custo marginal de capacidade do sistema, possibilita que sejam observadas melhores condições operacionais da rede. A aplicação da nova estrutura tarifária horária indica uma significativa alteração no perfil de carga esperado dos consumidores de baixa tensão o que refletiu em melhores valores de níveis de tensão e aumento da capacidade livre do transformador em integrar novas fontes distribuídas no sistema. / In planning the integration of distributed generation sources in the low voltage distribution system, it is essential to investigate the effects caused by the network operating conditions, such as voltage levels and transformer loading. By the point of view of the potential increase in photovoltaic generation for the Brazilian scenario and the imminent technological migration of traditional networks to the so-called Smart Grids, demand response is one of the strategies to enable the efficient integration of distributed energy resources. By applying a demand response program, specifically for the scenario of a distribution company, it was possible to conclude, by using real data, that in the integration planning process of new photovoltaic based generation sources, the application of a tariff structure with hourly differentiated costs based on the system's marginal cost of capacity, allows better operational conditions of the network to be observed. The application of the new hourly tariff structure indicates a significant change in the expected load profile of the low voltage consumers, which reflected in better values of voltage levels and rising of the free capacity of the transformer to integrate new distributed sources into the system.
105

Desenvolvimento de metodologias para localização de defeitos em sistemas de distribuição com medidores inteligentes / Protection and control systems analysis of industrial plants with synchronous generators during islanded operation

Arioli, Fernanda Caseño Trindade, 1984- 23 August 2018 (has links)
Orientador: Walmir de Freitas Filho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-23T18:19:46Z (GMT). No. of bitstreams: 1 Trindade_FernandaCasenoLima_D.pdf: 1722766 bytes, checksum: dec87e1e3e98a246135a42def8eef876 (MD5) Previous issue date: 2013 / Resumo: Atualmente, cargas de diversos tipos de consumidores têm se tornado cada vez mais sensíveis a variações e interrupções de energia. Na maioria das vezes, falhas no fornecimento de energia são resultados da ocorrência de defeitos (faltas) em sistemas de distribuição de energia elétrica. Estes defeitos prejudicam a confiabilidade do fornecimento de energia e podem resultar em afundamento de tensão, interrupções momentâneas ou sustentadas e em elevados custos operacionais. Em vista disto, cada vez mais, os consumidores estão conscientes sobre o assunto e observa-se a necessidade da elaboração de soluções eficientes para melhorar os índices de confiabilidade e de qualidade do fornecimento de energia elétrica. Um dos métodos mais eficazes para melhorar os índices de confiabilidade e qualidade de energia elétrica em sistemas de distribuição consiste no desenvolvimento de técnicas rápidas e precisas de localização de defeitos na rede. Embora os métodos de localização de defeito empregados em alimentadores de distribuição ainda sejam rudimentares, a integração de técnicas de medição, comunicação, do conhecimento da configuração da rede e atuação de religadores em tempo real, além de dados provenientes dos Sistemas de Informações Geográficas em sistemas de distribuição permite o desenvolvimento de métodos mais eficientes, que exploram informações provenientes de diferentes locais da rede (informações distribuídas) e não apenas da subestação. Neste contexto, este trabalho explora métodos de localização de defeitos baseados em medidas de tensão provenientes de diferentes locais de modernos sistemas de distribuição. Três métodos foram investigados: (1) o primeiro, baseado na correspondência de valores de tensão, utiliza os parâmetros elétricos da rede e duas ou mais medidas de tensão ao longo do alimentador; (2) o segundo método, baseado na correspondência da corrente de falta, utiliza os parâmetros elétricos da rede e uma quantidade maior de medidas de tensão que o primeiro método; (3) finalmente, o terceiro método, baseado no mapeamento das zonas de tensão reduzida, não necessita do conhecimento completo dos parâmetros da rede, no entanto, é necessário utilizar uma maior quantidade de medidores que nos outros dois métodos. Os resultados dos testes realizados mostram que de acordo com a disponibilidade de medição de tensão ao longo do alimentador, um destes métodos pode ser escolhido para localizar o defeito de maneira eficaz / Abstract: Nowadays, loads from different classes of customers have become more sensitive to variations and interruptions from power supply. Frequently, failures in electrical energy delivery are caused by occurrences of faults in distribution systems. Such faults decrease the reliability of power delivery, increase operational costs and may result in power quality problems, such as voltage sag, short or long term outages. Since the customers consciousness is increasing, the need of efficient solutions to improve reliability and power quality indices is also increasing. One of the most efficient approaches to improve such indices in distribution systems is to develop fast and accurate fault location techniques for aerial feeders. Even though fault location methods dedicated to distribution feeders are still rudimentary, the recent integration of measurement, communication, real time knowledge of feeder configuration and reclosers trip and Geographic System Information allows the development of more efficient solutions, which explores information from different places from the grid (distributed information) and not only from the substation. In this context, this work explores fault location methods based on voltage measurements applied to modern distribution systems. Three methods were investigated: (1) the first one is based on matching voltage values, this method requires the network electrical parameters and two or more voltage meters installed along the feeder; (2) the second method is based on the correspondence of fault current, this method uses the network electrical parameters and a higher quantity of meters than the first method; (3) finally, the third method is based on the identification of low voltage zones, this method does not require network electrical parameters, however it needs a higher quantity of voltage meters than the other two methods. The test results show that according to the voltage measurement availability along the feeder, one of these methods can be chosen to efficiently locate the fault / Doutorado / Energia Eletrica / Doutora em Engenharia Elétrica
106

Možnosti provozu sítě se zdroji rozptýlené výroby v ostrovním provozu / Options of network operation with distributed generation sources in island operation

Mareček, Tomáš January 2018 (has links)
This diploma thesis presents managing of the island mode using distributed generation. In the theoretical part of the thesis, the power system of the Czech Republic is described, together with its future development, and future development of installed capacity of distributed generation. Types of distributed generation are also mentioned. Next part of this work is focused on technological parts of islanding operation and its requirements. The following part describes components of the smart grids and mentions some of its functionalities. The practical part of the thesis describes the created models of components in PSCAD programme. From those components two slightly different grid models are created. On those grid models, simulations are made, during which island mode is created. Some of the grid functionalities are tested during those simulations, for example; reaction of the island mode for load increase, load decrease and others.
107

Privacy-Preserving Quantization Learning for Distributed Detection with Applications to Smart Meters / Apprentissage de quantificateurs pour la détection distribuée préservant la confidentialité, avec application aux compteurs intelligents

Mhanna, Maggie 13 January 2017 (has links)
Cette thèse porte sur quelques problèmes de codage de source dans lesquels on souhaite préserver la confidentialité vis à vis d’une écoute du canal. Dans la première partie, nous fournissons des nouveaux résultats fondamentaux sur le codage de source pour la détection (utilisateur légitime) et la confidentialité (vis à vis d’une écoute du canal) en présence d'informations secondaires aux terminaux de réception. Nous proposons plusieurs nouveaux résultats d'optimisation de la région de débit-erreur-équivocation réalisable, et proposons des algorithmes pratiques pour obtenir des solutions aussi proches que possible de l'optimal, ce qui nécessite la conception de quantificateurs en présence d'un eavesdropper. Dans la deuxième partie, nous étudions le problème de l'estimation sécurisée dans un cadre d'utilité-confidentialité où l'utilisateur recherche soit à extraire les aspects pertinents de données complexes ou bien à les cacher vis à vis d'un eavesdropper potentiel. L'objectif est principalement axé sur l'élaboration d'un cadre général qui combine la théorie de l'information et la théorie de la communication, visant à fournir un nouvel outil pour la confidentialité dans les Smart Grids. D'un point de vue théorique, cette recherche a permis de quantifier les limites fondamentales et donc le compromis entre sécurité et performance (estimation / détection). / This thesis investigates source coding problems in which some secrecy should be ensured with respect to eavesdroppers. In the first part, we provide some new fundamental results on both detection and secrecy oriented source coding in the presence of side information at the receiving terminals. We provide several new results of optimality and single-letter characterization of the achievable rate-error-equivocation region, and propose practical algorithms to obtain solutions that are as close as possible to the optimal, which requires the design of optimal quantization in the presence of an eavesdropper In the second part, we study the problem of secure estimation in a utility-privacy framework where the user is either looking to extract relevant aspects of complex data or hide them from a potential eavesdropper. The objective is mainly centered on the development of a general framework that combines information theory with communication theory, aiming to provide a novel and powerful tool for security in Smart Grids. From a theoretical perspective, this research was able to quantify fundamental limits and thus the tradeoff between security and performance (estimation/detection).
108

Open business models for future smart energy:a value perspective

Xu, Y. (Yueqiang) 22 November 2019 (has links)
Abstract Energy is essential for our lives and underpins all the key functions of society. However, our energy systems today are undergoing substantial changes. The growing energy demand and our dependence on fossil fuels have become an important issue faced by countries around the globe. Besides the technological developments in the field of renewables and smart grids for future smart energy, a significant weakness of our energy systems is their lack of social and economic perspectives, even though energy systems are often defined as techno-social systems. Through an extensive literature review of extant studies related to various aspects of energy and business model studies, this study has identified a major gap in that the business model and the value perspective have not been conceptualized with well-defined and holistic theoretical frameworks. Particularly, there is little understanding of the creation of open business models in digitalized industries, although the phenomenon is widespread in the real world. The main purpose of this research is to explore and understand the creation of open business models from the value perspective in the emerging smart energy ecosystem with a specific focus on value configurations. The study utilizes a system- and design-oriented action research approach and takes an energy innovation project funded by the European Union (EU) as the main data source. The results of the study are that: 1) the study proposes a holistic framework for the value perspective for (open) business models including value spaces, value configuration, and value complementarity. This is a major contribution to business model and management studies, and for the first time, it unifies the value thinking scattered throughout the existing literature; 2) the research provides an insight into how practitioners can conceptualize and approach the creation of open business models that are often enabled through digitalization; 3) the study contributes to the EU’s 2020 and 2030 energy and environmental targets. The research on new business models for the energy industry can assist in the implementation of new energy market development, policy instruments, and market regulations that promote the creation of smart grids, all of which are currently boosting jobs, economic growth, and environmental sustainability in Europe and elsewhere. / Tiivistelmä Nykyinen fossiilisista energianlähteistä riippuvainen energiajärjestelmämme on globaalissa muutoksessa energian kysynnän kasvaessa. Tulevaisuuden älykkäissä sähköverkoissa – ja koko energiajärjestelmässä – uusiutuvien energialähteiden rooli kasvaa huomattavasti. Vaikka energiajärjestelmät usein ymmärretäänkin sosio-teknisinä järjestelminä, ovat taloudelliset ja sosiaaliset näkökulmat jääneet aikaisemmassa tutkimuksessa usein teknisten näkökulmien varjoon. Tässä tutkimuksessa keskitytäänkin arvonluontiin ja liiketoimintamalleihin tulevaisuuden älykkäissä sähköverkoissa. Tutkimuksessa tehdyn ja energialiiketoimintaan kohdistuneen kirjallisuusanalyysin tuloksena voitiin todeta, että aikaisemmassa tutkimuksessa sovelletut liiketoimintamalli- tai arvonluonnin näkökulmat eivät muodosta riittävää ja kokonaisvaltaista viitekehystä älykkäiden sähköverkkojen tutkimukseen. Erityiseksi tutkimusaukoksi havaittiin avoimien ja digitaalisten liiketoimintamallien luominen energia-alalla. Tämän tutkimuksen tarkoituksena onkin ymmärtää, erityisesti arvon luonnin näkökulmasta, kuinka uusissa ja esiin nousevissa energiaekosysteemeissä syntyy ja luodaan avoimia liiketoimintamalleja ja arvokonfiguraatioita. Tutkimuksessa sovelletaan systeemi- ja suunnitteluorientoitunutta toimintatutkimusmetodologiaa, ja sen tutkimusaineisto on kerätty osana EU Horizon 2020 -ohjelmasta rahoitettua P2P-Smartest -hanketta. Tutkimuksen tuloksena esitetään 1) kokonaisvaltainen viitekehys avoimien liiketoimintamallien ymmärtämiseen arvonluonnin näkökulmasta. Viitekehys sisältää arvon luonnin alueen (value space), arvokonfiguraation (value configuration) ja arvon täydentävyyden (value complementarity) ulottuvuudet ekosysteemisessä kontekstissa. Lisäksi työssä esitetään näkökulmia, kuinka 2) käytännössä voidaan konseptoida ja luoda avoimia digitaalisia liiketoimintamalleja älykkäiden sähköverkkojen kontekstiin. Toteutetun liiketoimintamallitutkimuksen tulokset tukevat myös 3) EU:n vuosille 2020 ja 2030 asetettujen energia- ja ympäristötavoitteiden saavuttamista erityisesti energiamarkkinan, markkinaregulaation ja -politiikkojen kehittämisessä sekä älykkäiden sähköverkkojen käyttöön ottamisessa.
109

Industrial Internet of Things Collaborations : A Contingency Framework for Smart Grid Development in Renewable Energy

Haglund, Leo, Jonsson, Emil January 2021 (has links)
Purpose - As energy demand increases in tandem with an increasing climate crisis, the world runs towards renewable energy generation. Within the area of Industrial Internet of Things (IIoT) there are a multitude of opportunities that should be capitalized on, but this requires an integration of the connected systems of Information Technology (IT) and the governing systems of Operational Technology (OT). In the utility sector, this has proven very complex. Hence, the purpose of this paper is to explore the challenges between utility companies, IT providers, and OT providers in the ecosystem to identify activities to combat these challenges by developing a contingency framework. Thus, contributing to the development of Smart Grids (SG) within renewable energy generation. Method – To fulfill the purpose of this study, the partnership between the Swedish branch of a global technology company and a sizeable Swedish energy producer has been investigated. A qualitative single case study has been conducted with an inductive, explorative approach. Empirical data were collected from 22 interviews and 4 workshops from six different companies across five countries. The interviews and workshops were conducted in three different waves: 1) Explorative, 2) Investigatory, and 3) Validatory. The data were analyzed using thematic analysis. Findings – Findings from our data analysis have identified challenges and key activities in four main categories: 1) IT/OT Collaborative Challenges, 2) IT/OT Technical Challenges, 3) IT/OT Collaborative Activities, and 4) IT/OT Technical Activities. These findings are combined to form a contingency framework that emphasizes the activities to overcome industry challenges. Theoretical and Practical Implications – Our findings and framework expand on current literature in IIoT, SGs, and Innovation Ecosystems development by investigating the collaborative challenges and activities within IT/OT collaboration rather than specific technologies or ecosystem structures. It also expands the literature on IT/OT convergence by taking a broader ecosystem perspective than only IT and OT companies. Our framework provides practical contributions for managers by identifying key challenges and activities and how these relate to each other. Limitations and Future Research – Our study is limited to a single case study on wind power generation in northern Europe. Therefore, future studies are recommended to investigate if our findings apply to other companies, industry sectors, and geographical areas.
110

Optimal resource allocation strategies for electric vehicles in smart grids / Stratégies optimales d'allocation des ressources pour véhicules électriques dans les réseaux intelligents

Alinia, Bahram 10 July 2018 (has links)
Avec les préoccupations environnementales croissantes liées aux émissions de carbone et la chute rapide des prix des batteries, la part de marché des véhicules électriques (EV) augmente rapidement. Le nombre croissant de EV ainsi que les progrès sans précédent dans la capacité de la batterie et de la technologie entraîne une augmentation drastique de la demande totale d'énergie destinée aux véhicules électriques. Cette forte demande de charge rend complexe le problème de planification de la charge. Même en prenant avantage de la propriété reportable des demandes de charge et d'une planification adéquate, la demande globale pourrait dépasser le taux de charge tolérable des stations, étant donné les contraintes physiques des dispositifs de charge et des transformateurs. Le principal défi est la nécessité de concevoir des solutions en ligne puisque, dans la pratique, l'ordonnanceur ne dispose d'aucune information sur les arrivées futures d'EV. Cette thèse étudie le problème d'ordonnancement des EV en ligne et fournit trois contributions principales. Premièrement, nous démontrons que le problème classique de la programmation en ligne des tâches sensibles aux échéances avec des valeurs partielles est similaire au problème d'ordonnancement EV et étudions l'extension de la programmation des charges EV en prenant en compte de la limite de traitement des travaux. Le problème réside dans la catégorie des problèmes d'ordonnancement en ligne couplés dans le temps sans disponibilité d'informations futures. Le premier algorithme proposé est déterministe, tandis que le second est randomisé et bénéficie d'une complexité de calcul plus faible. Deuxièmement, nous formulons un problème de maximisation du bien-être social pour la planification de la charge des EV avec une contrainte de capacité de charge. Nous avons conçu des algorithmes d'ordonnancement de charge qui non seulement fonctionnent dans un scénario en ligne, mais aussi qui répondent aux deux principaux défis suivants : (i) fournir un engagement à l'arrivée ; (ii) garantir la résistance aux stratégies (de groupe). Des simulations approfondies utilisant des traces réelles démontrent l'efficacité de nos algorithmes d'ordonnancement en ligne par rapport à la solution hors-ligne optimale non-engagée. La troisième contribution concerne la planification en ligne des véhicules électriques dans un réseau de recharge adaptatif (ACN) avec des contraintes de pics locaux et globaux. Nous avons conçu un algorithme d'ordonnancement primal-dual de faible complexité qui atteint un rapport d'approximation borné. Des résultats expérimentaux détaillés basés sur des traces montrent que les performances des algorithmes en ligne proposés sont proches de l'optimum hors ligne et surpassent les solutions existantes / With the increased environmental concerns related to carbon emission, and rapid drop in battery prices (e.g., 35% drop in 2017), the market share of Electric Vehicles (EVs) is rapidly growing. The growing number of EVs along with the unprecedented advances in battery capacity and technology results in drastic increase in the total energy demand of EVs. This large charging demand makes the EV charging scheduling problem challenging. The critical challenge is the need for online solution design since in practical scenario the scheduler has no information of future arrivals of EVs in a time-coupled underlying problem. This thesis studies online EV scheduling problem and provides three main contributions. First, we demonstrate that the classical problem of online scheduling of deadlinesensitive jobs with partial values is similar to the EV scheduling problem and study the extension to EV charging scheduling by taking into account the processing rate limit of jobs as an additional constraint to the original problem. The problem lies in the category of time-coupled online scheduling problems without availability of future information. Using competitive ratio, as a well-established performance metric, two online algorithms, both of which are shown to be (2 − 1/U)-competitive are proposed, where U is the maximum scarcity level, a parameter that indicates demand-to-supply ratio. Second, we formulate a social welfare maximization problem for EV charging scheduling with charging capacity constraint. We devise charging scheduling algorithms that not only work in online scenario, but also they address the following two key challenges: (i) to provide on-arrival commitment; respecting the capacity constraint may hinder fulfilling charging requirement of deadline-constrained EVs entirely. Therefore, committing a guaranteed charging amount upon arrival of each EV is highly required; (ii) to guarantee (group)-strategy-proofness as a salient feature to promote EVs to reveal their true type and do not collude with other EVs. Third, we tackle online scheduling of EVs in an adaptive charging network (ACN) with local and global peak constraints. Two alternatives in resource-limited scenarios are to maximize the social welfare by partially charging the EVs (fractional model) or selecting a subset of EVs and fully charge them (integral model). For the fractional model, both offline and online algorithms are devised. We prove that the offline algorithm is optimal. We prove the online algorithm achieves a competitive ratio of 2. The integral model, however, is more challenging since the underlying problem is NP-hard due to 0/1 selection criteria of EVs. Hence, efficient solution design is challenging even in offline setting. We devise a low-complexity primal-dual scheduling algorithm that achieves a bounded approximation ratio. Built upon the offline approximate algorithm, we propose an online algorithm and analyze its competitive ratio in special cases

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