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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.
251

Aplicação de sistema especialista para localização de defeitos em redes de distribuição. / Expert system application for fault location in distribution networks.

Rufato Júnior, Elói 16 July 2015 (has links)
Com o objetivo de orientar e agilizar a busca do local de curto circuitos em redes primárias aéreas de distribuição de energia, esta pesquisa propõe uma metodologia para localização de áreas com maior probabilidade de ser sede do defeito, utilizando variáveis Heurísticas. A metodologia Heurística se aplica em problemas que envolvem variáveis com incertezas, que podem ser avaliadas por meio de recursos empíricos e na experiência de especialistas. Dentre as variáveis influentes no cálculo de curto circuito, foram consideradas como mais relevantes: a resistência de defeito, a tensão pré falta, a impedância do sistema equivalente a montante da subestação e a impedância da rede. A metodologia proposta se fundamenta no conhecimento das correntes e tensões oscilografadas no barramento da subestação por ocasião da ocorrência de um curto circuito e, por outro lado no pré-calculo de correntes de curto circuito heurísticas ao longo da rede. No âmbito da pesquisa foram realizados testes de campo para levantamento da variável heurística resistência de defeito, resumidos neste texto e documentados no CD - ROM em anexo. Foi desenvolvido um software que permitiu a efetiva aplicação da proposta desta pesquisa em vários alimentadores de uma Distribuidora, cujos resultados comprovaram a eficiência da metodologia. / With the aim of guiding and speeding up the search of a short circuits place in primary networks of energy distribution this research proposes a methodology for locating higher probability areas of fault, making use of Heuristic variables. The Heuristic methodology is applied in problems that involve variables with uncertainties, which can be evaluated with empirical tools and specialists experience. Among the influential variables in the short circuit calculation, as most relevant were considered: the faults resistance, the pre fault tension, the equivalent system impedance upstream of the substation and the electrical grid impedance. The proposed methodology relies on the knowledge of currents and tensions oscillografed in the substation bus in consequence of a short circuit and, in another way on the pre calculation of heuristic short circuit currents along the grid. In the research scope field tests were performed with the aim of collecting the fault resistance heuristic variable, resumed in this text and documented on the CD-ROM attached. A software that allowed the actual implementation of this researchs purpose in various feeders of a distributor has been developed, with results that confirmed the efficiency of this methodology.
252

Μελέτη προβλήματος κατανεμημένης παραγωγής στα συστήματα ηλεκτρικής ενέργειας

Λάμπρου, Λάζαρος, Σταφυλιάς, Σπυρίδων 28 August 2009 (has links)
Σε αυτή τη διπλωματική εργασία διερευνούνται οι προδιαγραφές που πρέπει να ικανοποιούνται ώστε να είναι εφικτή η σύνδεση εγκαταστάσεων κατανεμημένης παραγωγής στα δίκτυα διανομής και η εφαρμογή τους σε ένα φωτοβολταϊκό σύστημα που συνδέεται στο δίκτυο χαμηλής τάσης. Στο πρώτο κεφάλαιο γίνεται μια επισκόπηση της παρούσας κατάστασης στην ηλεκτρική ενέργεια και αναλύονται οι λόγοι που οδήγησαν στην ανάπτυξη της κατανεμημένης παραγωγής οι οποίοι συνοψίζονται στους περιορισμούς στην κατασκευή νέων γραμμών μεταφοράς, στην αυξημένη ζήτηση παροχής ηλεκτρικής ενέργειας υψηλής αξιοπιστίας, στην απελευθέρωση της αγοράς ηλεκτρικής ενέργειας, στους προβληματισμούς για τις κλιματικές αλλαγές και στην εξάντληση των ορυκτών καυσίμων. Έπειτα αναλύεται ο ορισμός της κατανεμημένης παραγωγής σύμφωνα με τα διάφορα διεθνή ινστιτούτα ηλεκτρικής ενέργειας και αναπτύσσονται οι τεχνολογίες που περιλαμβάνει οι οποίες διαχωρίζονται σε τεχνολογίες φυσικού καυσίμου (fossil fuel technologies) και σε ανανεώσιμες πηγές ενέργειας. Στις πρώτες περιλαμβάνονται οι μηχανές εσωτερικής καύσης, οι αεριοστροβιλικοί σταθμοί, οι μικροστρόβιλοι ή μικροτουρμπίνες και οι σταθμοί συνδυασμένου κύκλου ενώ στις ανανεώσιμες πηγές ενέργειας περιλαμβάνονται οι ανεμογεννήτριες, τα κύτταρα καυσίμου (fuel cells), οι φωτοβολταϊκές γεννήτριες, τα μικρά υδροηλεκτρικά και οι μονάδες παραγωγής ηλεκτρικής ενέργειας από βιομάζα και φυσικό αέριο. Η λειτουργία ενός ηλεκτρικού δικτύου ελέγχεται από συσκευές προστασίας και ρύθµισης της τάσης, που έχουν σκοπό την παροχή προς τους καταναλωτές ηλεκτρικής ενέργειας αποδεκτής ποιότητας, ελαχιστοποιώντας τον αριθµό των σφαλµάτων και προσφέροντας υψηλό επίπεδο ασφάλειας. Η σύνδεση στο δίκτυο µονάδων κατανεμημένης παραγωγής πρέπει να συµβαδίζει µε αυτές τις γενικές αρχές, ώστε αφενός µεν να µην προκαλούνται ενοχλήσεις στους λοιπούς καταναλωτές και αφετέρου να υπάρχει συµβατότητα µεταξύ του δικτύου διανοµής και των εγκαταστάσεων των παραγωγών. Στο δεύτερο κεφάλαιο αναφέρονται οι προϋποθέσεις που πρέπει να ισχύουν για τη σύνδεση και παράλληλη λειτουργία των εγκαταστάσεων παραγωγής µε τα δίκτυα διανοµής, καθώς και ο απαιτούµενος εξοπλισµός ζεύξης και προστασίας, µε στόχο την αποτελεσµατική αντιµετώπιση της πλειονότητας των περιπτώσεων. Οι τεχνικές προδιαγραφές που περιγράφονται αφορούν στη σύνδεση παραγωγών στο δίκτυο µέσης τάσης (ΜΤ) ή χαµηλής τάσης (ΧΤ). Βασικά κριτήρια και προϋποθέσεις που εξετάζονται προκειµένου να επιτραπεί η σύνδεση νέων εγκαταστάσεων παραγωγής είναι η επάρκεια του δικτύου (γραμμών, μετασχηματιστών κλπ.), η συµβολή στη στάθµη βραχυκύκλωσης, οι αργές µεταβολές της τάσης (µόνιµης κατάστασης), οι ταχείες µεταβολές της τάσης, οι εκποµπές flicker, οι εκπομπές αρμονικών, η διαµόρφωση των προστασιών της διασύνδεσης εγκαταστάσεων-δικτύου και η επίπτωση στη λειτουργία συστηµάτων Τηλεχειρισµού Ακουστικής Συχνότητας (ΤΑΣ). Τα κριτήρια και οι µέθοδοι εξέτασης που περιγράφονται στηρίζονται κατά κύριο λόγο στη σειρά προτύπων 61000 της IEC (International Electrotechnical Commission) και εξασφαλίζουν την ικανοποίηση των απαιτήσεων του ευρωπαϊκού προτύπου ΕΝ 50160 (πρότυπο ΕΛΟΤ ΕΝ 50160 και Οδηγία διανοµής 120 της ΔΕΗ Α.Ε.). Στο τρίτο κεφάλαιο πραγματοποιείται μια μελέτη εφαρμογής των παραπάνω προδιαγραφών σε ένα σύστημα που εξομοιώθηκε με χρήση του προγράμματος PSCAD. Το σύστημα αποτελείται από μια φωτοβολταϊκή συστοιχία μέγιστης ισχύος 4,8 kW, έναν μετατροπέα συνεχούς/εναλλασσόμενης τάσης ή αντιστροφέα (DC to AC converter) που λειτουργεί με τη μέθοδο PWM (Pulse Width Modulation ή διαμόρφωση εύρους παλμού), ένα σύστημα παρακολούθησης του σημείου μέγιστης ισχύος που αποδίδει η συστοιχία (MPPT Maximum Power Point Tracker), ένα μετασχηματιστή 150V/380V για την ανύψωση της τάσης στην έξοδο του αντιστροφέα στα επίπεδα τάσης του δικτύου, ένα δίκτυο χαμηλής τάσης και δύο φορτία RL. Εκτενής αναφορά γίνεται στις εκπομπές αρμονικών που παρουσιάζονται στο σύστημα στην έξοδο του αντιστροφέα. Αρχικά γίνεται μελέτη χωρίς φίλτρο LC στην έξοδο του αντιστροφέα και στη συνέχεια παρατηρούμε τον τρόπο με τον οποίο το φίλτρο LC επιδρά στη μείωση των αρμονικών σε επιτρεπτά πλαίσια. Τέλος διερευνούνται οι διακυμάνσεις τάσης του δικτύου κατά τη ζεύξη του φωτοβολταϊκού συστήματος με το δίκτυο, πραγματοποιείται μια μελέτη του συστήματος σε περίπτωση βραχυκυκλωμάτων και διερευνάται η επίπτωση σε συστήματα τηλεχειρισμού ακουστικής συχνότητας. / -
253

Development Of Algorithms For Fault Detection In Distribution Systems

Ersoi, Moustafa 01 December 2003 (has links) (PDF)
In this thesis, the possibility of detection of fault location in the cable distribution systems by using traveling waves due to fault and circuit breaker operations is investigated. Waveforms originated from both actions and fault steady state are separately analyzed. During such switching actions, high frequency variations which are absent in the steady state conditions, take place. In order to simulate high frequency changes properly, system elements are modeled accordingly. In other words, frequency dependent models are introduced, and they are used in Electro-Magnetic Transients Program (EMTP). Since the characteristics of waveforms are different for separately analyzed portions, different fault locating algorithms with their limitations are introduced.
254

Acquisition of electronic commerce capability : the cases of Compaq and Dell in Sweden

Kaplan, Michael January 2002 (has links)
Electronic commerce is in a state of growth and the number of firms engaging in electronic commerce has increased rapidly during the late 1990s. As a result, electronic commerce has become an essential part of commercial life. As firms have struggled to implement electronic commerce there have been successes and failures. Hence there is a need to improve our understanding of how electronic commerce can and should be deployed.  In this thesis electronic commerce is explored and discussed in terms of what firms need to know and how they can acquire that knowledge in order to engage in electronic commerce to remain or become competitive. The focus is on the process of acquiring new capabilities for electronic commerce. Capabilities are regarded as high-performance routines that can reside within and between organisations and confer a firm with a temporary competitive advantage. These capabilities can be acquired by utilisation of four categories of means: in-house innovation, cloning, collaboration and firm purchasing.  Four hypothesises for understanding and explaining capability acquisition are formulated with regard to how the means can be used. By surveying the literature, drawing on numerous research traditions in an eclectic manner, it is posited that the supply of capabilities, the current capability portfolio, the nature and maturity of the firm trajectory, and the performance of the firm influence the capability acquisition process.  The cases of Compaq and Dell in Sweden are employed to investigate the issue of capability acquisition. Compaq has utilised an indirect approach working through intermediaries, while Dell has utilised a direct approach working directly with customers. The cases are analysed with the four hypothesises. Five capabilities are identified as critical for electronic commerce: addressability, interactivity, customisation, personalisation and postponement. It is shown that these capabilities are acquired in a process following a trajectory. This process involves suppliers, partners, customers and competitors. It is shown that firms working indirectly acquire capabilities mainly from competitors. In contrast, firms working directly acquire capabilities mainly from customers. Furthermore, working directly with customers – as opposed to working indirectly – is found to be a good vehicle for acquiring electronic commerce capability. / Diss. Stockholm : Handelshögsk., 2002
255

Despacho de reativos para regulação de tensão em redes de média tensão com geradores fotovoltaicos / Despacho de reactivos para regulación de tensión en redes de media tensión con generadores foto-voltaicos

Negreiros Terrones, John William 06 September 2017 (has links)
Submitted by JOHN WILLIAM NEGREIROS TERRONES null (johneter@hotmail.com) on 2018-01-19T17:02:53Z No. of bitstreams: 1 DissertaçãoJohn_JB (1).pdf: 14046795 bytes, checksum: deeec72b971c8015d40780ccc3ee8e37 (MD5) / Approved for entry into archive by Cristina Alexandra de Godoy null (cristina@adm.feis.unesp.br) on 2018-01-19T17:54:25Z (GMT) No. of bitstreams: 1 terrones_jwn_me_ilha.pdf: 14046795 bytes, checksum: deeec72b971c8015d40780ccc3ee8e37 (MD5) / Made available in DSpace on 2018-01-19T17:54:25Z (GMT). No. of bitstreams: 1 terrones_jwn_me_ilha.pdf: 14046795 bytes, checksum: deeec72b971c8015d40780ccc3ee8e37 (MD5) Previous issue date: 2017-09-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Neste trabalho, propõe-se uma metodologia baseada nas incertezas da radiação solar para prever o despacho de demanda e reativos nos sistemas de distribuição radial com geradores fotovoltaicos (GFs). O objetivo dessa metodologia é melhorar o perfil da magnitude de tensão para o dia seguinte, sujeito a certas restrições operativas do sistema elétrico de distribuição. No desenvolvimento dos algoritmos de solução são considerados geradores distribuídos que têm forte dependência das variações da fonte primária de energia (principalmente sistemas fotovoltaicos), ou seja, os limites de injeção de potência dos GFs dependem das incertezas da radiação solar. Este grupo de geradores precisa de considerações que incluam as incertezas na geração de energia. Para isso, elaboram-se cenários de radiação baseado na função de distribuição de probabilidade beta. Assim, são realizados fluxos de potência probabilísticos em múltiplos cenários. Leva-se em consideração, os objetivos a serem otimizados por meio de técnicas multiobjetivo, observando principalmente, os desvios da tensão nos nós e as perdas de potência nas linhas do sistema. A metodologia proposta foi implementada em linguagem de modelagem algébrica com o AMPL para descrever o problema de otimização e resolvido usando o solver comercial CPLEX. Os sistemas testes de 34 e 123 nós foram utilizados para avaliar os modelos matemáticos e a eficiência da técnica de solução proposta para o problema de controle dos sistemas de distribuição radiais com GFs. / This work presents a methodology based on uncertainties of solar radiation to predict demand and reactive dispatch in the radial distribution systems with photovoltaic generators (GFs). The objective is to improve the voltage magnitude profile for a day ahead, subjecting to operation constraints of distribution system. In order to evaluate the optimization criteria for distribution networks, active power balance equations have to be solved. It is considered that distributed generators have a high coherence to variations of the primary energy source (mainly photovoltaic systems), where, the power injection limits of the GFs depend on the uncertainties of the solar radiation. Uncertainties in generation are needed to be considered for this type of generator. Thus, the beta probability distribution function has been employed to include different radiation scenarios in the problem formulation. The aim of this research evolves the development of an optimization tool to predict the reactive power dispatch of GFs considering the uncertainties of solar radiation. For this purpose, the probabilistic power flow is performed under various scenarios. The Multiobjective optimization problem is formulated by including the buses (nodes) voltage deviations and the power losses of distribution lines in two different objective functions. The proposed methodology was implemented in AMPL mathematical model language and solved using the commercial CPLEX solver. The 34 and 123 nodes test systems are applied to show efficiency of presented mathematical models, i.e. control of radial distribution systems with GFs, and the proposed solution method.
256

Despacho de reativos para regulação de tensão em redes de média tensão com geradores fotovoltaicos /

Negreiros Terrones, John William January 2017 (has links)
Orientador: Antonio Padilha Feltrin / Resumo: Neste trabalho, propõe-se uma metodologia baseada nas incertezas da radiação solar para prever o despacho de demanda e reativos nos sistemas de distribuição radial com geradores fotovoltaicos (GFs). O objetivo dessa metodologia é melhorar o perfil da magnitude de tensão para o dia seguinte, sujeito a certas restrições operativas do sistema elétrico de distribuição. No desenvolvimento dos algoritmos de solução são considerados geradores distribuídos que têm forte dependência das variações da fonte primária de energia (principalmente sistemas fotovoltaicos), ou seja, os limites de injeção de potência dos GFs dependem das incertezas da radiação solar. Este grupo de geradores precisa de considerações que incluam as incertezas na geração de energia. Para isso, elaboram-se cenários de radiação baseado na função de distribuição de probabilidade beta. Assim, são realizados fluxos de potência probabilísticos em múltiplos cenários. Leva-se em consideração, os objetivos a serem otimizados por meio de técnicas multiobjetivo, observando principalmente, os desvios da tensão nos nós e as perdas de potência nas linhas do sistema. A metodologia proposta foi implementada em linguagem de modelagem algébrica com o AMPL para descrever o problema de otimização e resolvido usando o solver comercial CPLEX. Os sistemas testes de 34 e 123 nós foram utilizados para avaliar os modelos matemáticos e a eficiência da técnica de solução proposta para o problema de controle dos sistemas de distribuição radia... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This work presents a methodology based on uncertainties of solar radiation to predict demand and reactive dispatch in the radial distribution systems with photovoltaic generators (GFs). The objective is to improve the voltage magnitude profile for a day ahead, subjecting to operation constraints of distribution system. In order to evaluate the optimization criteria for distribution networks, active power balance equations have to be solved. It is considered that distributed generators have a high coherence to variations of the primary energy source (mainly photovoltaic systems), where, the power injection limits of the GFs depend on the uncertainties of the solar radiation. Uncertainties in generation are needed to be considered for this type of generator. Thus, the beta probability distribution function has been employed to include different radiation scenarios in the problem formulation. The aim of this research evolves the development of an optimization tool to predict the reactive power dispatch of GFs considering the uncertainties of solar radiation. For this purpose, the probabilistic power flow is performed under various scenarios. The Multiobjective optimization problem is formulated by including the buses (nodes) voltage deviations and the power losses of distribution lines in two different objective functions. The proposed methodology was implemented in AMPL mathematical model language and solved using the commercial CPLEX solver. The 34 and 123 nodes test systems a... (Complete abstract click electronic access below) / Mestre
257

Uma nova metodologia para o desenvolvimento de projetos de proteção de redes ativas de distribuição de energia elétrica /

Conceição, Katiani Pereira January 2018 (has links)
Orientador: Javier Sanz Contreras / Resumo: Neste trabalho, apresenta-se uma nova proposta de metodologia para alocar, determinar e es-pecificar os tipos de dispositivos de controle e proteção em redes de distribuição com geração distribuída (GD). Esta metodologia é baseada em técnicas de otimização multiobjetivo para efetuar a alocação otimizada, coordenada e seletiva destes dispositivos. O modelo é composto por duas funções objetivo que consideram aspectos econômicos e da confiabilidade da rede, e um conjunto de restrições composto por restrições físicas, operacionais e um subconjunto de restrições baseadas em regras práticas das empresas do setor de distribuição e previstas em normas técnicas nacionais e internacionais que estabelecem a especificação, coordenação e seletividade dos dispositivos de controle e proteção instalados na rede. No modelo considera-se a possibilidade de transferência de carga entre alimentadores vizinhos e a operação ilhada da GD. Dessa forma, obtém-se um modelo genérico de programação não linear inteira mista (PNLIM) cujo diferencial com relação a outros modelos matemáticos da literatura é propor que no mesmo processo de otimização seja realizada a alocação otimizada dos dispositivos de controle e proteção na rede juntamente com a coordenação do sistema de proteção. A eficiên-cia do modelo matemático é comprovada comparando-se os resultados obtidos entre dois tes-tes com o auxílio do algoritmo genético (AG) mono-objetivo que considera a ponderação dos objetivos, enquanto que para a solução ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This paper, presents a new methodology for placing, selecting and specifying the control and the protective devices system of distribution networks with distributed generation (DG). This methodology is based on multiobjective optimization techniques to perform the optimized, coordinated and selective allocation of the control and protective devices. The proposed mathematical model consists of two objective functions that consider economic factors and network continuity indexes. Physical and operational constraints are taken into account, with an emphasis on the set of constraints based on practical rules of distribution utilities defined in international technical standards, which require the specification, coordination, and selectivity of protective devices installed in the network. The possibility of load transfer from neighboring feeders and the islanded DG operation are also considered in the model. In this way, we obtain a generic model of mixed-integer nonlinear programming (MINLP) whose differential in relation to other mathematical models of the literature is to propose, in the same optimization process, the optimized allocation of the control and protective devices in the network along with the coordination of the protection system. The efficiency of the mathematical model is proven by comparing the results obtained in two tests with the aid of the genetic algorithm (GA) while for the solution of the multiobjective MINLP model the NSGA-II multiobjective genetic algor... (Complete abstract click electronic access below) / Doutor
258

Modelos matemáticos para otimização da confiabilidade de sistemas elétricos de distribuição com geração distribuída

Ferreira, Gustavo Dorneles January 2013 (has links)
sensíveis têm requerido elevados níveis de confiabilidade dos sistemas de distribuição de energia. Em meio a este cenário, a proliferação de geradores distribuídos conectados próximos às cargas evidencia o surgimento de um novo paradigma na produção e utilização da energia elétrica. No entanto, muitos problemas decorrem do fato de que os sistemas de distribuição não foram projetados para incorporar unidades geradoras de energia. A estratégia completa de controle e proteção é definida sob o pressuposto do fluxo unidirecional de potência nos alimentadores. Um dos conflitos mais imediatos que surgem com a penetração da geração distribuída é relacionado ao sistema de proteção, resultado da alteração na magnitude das correntes de falta. Algumas consequências são a perda da sensibilidade e da coordenação da proteção. Se contornados estes problemas, a geração distribuída tem potencial para exercer impacto positivo sobre a confiabilidade, em especial no suporte ao restabelecimento da carga em situações de contingência. Tendo em vista estes fatores, a metodologia proposta adota uma perspectiva multicriterial para otimizar o desempenho dos sistemas de distribuição na presença da geração distribuída. Os indicadores SAIDI, SAIFI e MAIFI são formulados como modelos de otimização que possibilitam a adequação do sistema de proteção às condições operacionais impostas pela geração distribuída. Dentre os aspectos considerados incluem-se a alocação, a seletividade e a coordenação dos dispositivos de proteção. A alocação de chaves de manobras para reconfiguração do alimentador é a estratégia adotada para maximizar o efeito positivo da geração distribuída sobre a confiabilidade. As soluções dos modelos definem os locais de instalação dos dispositivos de proteção e manobras, e os ajustes dos religadores de forma independente para as unidades de fase e terra. A minimização simultânea dos indicadores é formulada como um problema de Programação Linear Inteira Mista por Metas, visando o balanço ótimo entre a redução das interrupções momentâneas e sustentadas nos sistemas de distribuição. Os modelos analíticos dos indicadores são solucionados utilizando um pacote de otimização de uso geral, baseado no método de Branch-and-Bound. A metodologia é avaliada a partir de um estudo de caso, considerando níveis crescentes de penetração da geração distribuída em um alimentador de distribuição real. Os modelos matemáticos são aplicados em cenários distintos de operação do sistema, associados à diferentes restrições econômicas. Os resultados possibilitam a avaliação do impacto da geração distribuída no restabelecimento e na proteção do sistema de forma independente. / The increasing automation of industrial processes and the sensitivity of electronic loads have required high levels of power distribution system’s reliability. In this scenario, the widespread use of distributed generators connected near the loads shows the emergence of a new paradigm in electric energy production and application. However, many problems arise from the fact that the distribution systems were not designed to deal with power generating units. The complete control and protection strategy is defined under the assumption of radial power flow. One of the most immediate conflicts that arise with the penetration of distributed generation is related to the protection system, a result of the change in fault currents magnitude. Some consequences are loss of protection coordination and sensitivity. By addressing these problems, distributed generation has the potential to have a positive impact on distribution reliability, especially in supporting load restoration during system’s contingencies. Considering these factors, the proposed methodology uses a multi-criteria approach to optimize the overall performance of distribution systems in the presence of distributed generation. The reliability indices SAIDI, SAIFI and MAIFI are formulated as optimization models that allow adequacy of the protection system in relation to the operating conditions imposed by distributed generation. The aspects considered include the allocation, selectivity and coordination of protective devices. The allocation of sectionalizing switches for feeder restoration is the strategy to maximize the positive impact of distributed generation on the system reliability. The model solutions provide the protective devices and switches locations, as well as reclosers’ settings for phase and ground units, independently. Reliability indices minimization is formulated as a Mixed Integer Linear Goal Programming problem, in order to establish the optimal trade-off between reducing momentary and sustained interruptions in distribution systems. The analytical models are solved using a general-use optimization package based on the Branch-and-Bound method. The methodology is evaluated through a case study considering increasing levels of distributed generation penetration on a real distribution feeder. The proposed mathematical models are applied in different scenarios of system operation and under different economic constraints. The results allow the evaluation of the impact of distributed generation on restoration and protection of the test system.
259

Développement de la gestion optimale de l'énergie électrique dans les îles Galápagos vers les Reséaux Intelligents / Development of optimal energy management in Galapagos Islands towards Smart Grid

Morales jadan, Diego 18 December 2017 (has links)
Les îles Galápagos sont un archipel d'îles volcaniques situées dans l'océan Pacifique, à 926 km à l'ouest de l'Equateur continental, dont elles font partie. Depuis 1978, les îles Galápagos sont déclarées patrimoine mondial. En raison de la croissance de la population, il existe plusieurs problèmes sociaux, économiques et environnementaux qui risquent la conservation de l'environnement des îles. Dans ce contexte, le gouvernement équatorien veut préserver son patrimoine écologique. Par conséquence, avec la participation de divers acteurs, principalement le ministère de l'Énergie et des Énergies renouvelables, il effectue plusieurs initiatives. Afin d'améliorer les services fournis sur les îles, cet objectif sera accompli grâce à la réduction de la consommation de carburants fossiles et donc des émissions de CO2. Donc, cette thèse a analysé l'impact des nouveaux services sur le réseau électrique, comme le remplacement obligatoire des véhicules conventionnels et des cuisinières pour des solutions efficaces et la proposition des solutions pour réduire les problèmes négatifs sur le réseau. En outre, une forte intégration de la génération distribuée a été considérée dans l'analyse. De plus, des solutions innovantes pour basse et moyenne tension ont été conçues et testées afin d’améliorer le service électrique sans affecter l'environnement et conserver ce patrimoine mondial. Par exemple, un programme DSM intelligent composé d'un schéma de temps d'utilisation (TOU) combiné avec la réponse de la demande (DR) a montré des résultats intéressants, l'installation d'un système de stockage d'énergie de batterie a également été testée, et les résultats de moyenne tension sont prometteurs. Un système de commutation automatique de phase a été adapté comme une solution pour réduire le déséquilibre en basse tension avec des résultats impressionnants. Le déploiement des réenclencheurs a démontré une amélioration considérable de la fiabilité avec un retour d’investissement très court. Considérant les technologies de l'information et de la communication, une pièce clé pour déployer Smart Grids, l'architecture de communication des réseaux de NAN/FAN/HAN a été abordée. Enfin, un Système de Gestion d’Energie pour la gestion optimale de l'énergie à Galápagos a été conçu. Toutes ces études représentent un défi important : la gestion optimale de l'électricité de réseau isolée sans énergie fossile. / The Galápagos Islands are an archipelago of volcanic islands located in the Pacific Ocean, 926 km west of continental Ecuador, of which they are a part. Since 1978, Galapagos Islands are accepted as Heritage World, due to the growth of the population, there are several social, economic and environmental problems, which endanger the environment conservation of the Islands.In this context, the Ecuadorian government desires to preserve its ecological heritage. Hence, with the participation of several stakeholders mainly the Ministry of Energy and Renewable Energy, it is releasing a lot of initiatives. In order to improve the general services that are provided in the islands, this goal will be achieved by means of reducing fossil fuel consumption and therefore CO2 emissions. Thus, this thesis has analyzed the impact of new services on the grid such as the mandatory replacement of conventional vehicles and cookers for efficient ones and to propose solutions for reducing negative issues originated on the network. Also, a strong integration of distributed generation is considered in the analysis.In addition, innovative solutions for both low and medium voltage have been designed and tested for improving the electrical service without affecting the environment and conserving this world heritage. For instance, a smart DSM program composed of Time of Use scheme combined with Demand Response has shown interesting results, the installation of a Battery Energy Storage System has been studied as well; the results in Medium Voltage are promising. An Automatic Phase Switching system is adapted like a solution for reducing unbalance in low voltage with impressive results. The deployment of reclosers has demonstrated a considerable improvement in the reliability with a Return on Investment very short.Considering the Information and Communication Technologies a key piece to deploy Smart Grids, the communication architecture of the Neighbor, Field and Home Area Networks is addressed. As last, an Energy Management System for performing optimal energy management within Galapagos is designed. All these studies have a significant challenge: the optimal management of electricity of isolated grid with zero fossil energy.
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Percepção da enfermagem e avaliação da segurança do paciente na implantação de dispensários eletrônicos

Pozza, Camila Pereira Menezes January 2016 (has links)
Objetivos: Conhecer a satisfação e a percepção da equipe de enfermagem usuária dos dispensários eletrônicos com relação a estes equipamentos e adaptar transculturalmente o instrumento ISMP Medication Safety Self Assessment® for Automated Dispensing Cabinets para a realidade brasileira. Métodos: O estudo foi realizado em duas etapas. A primeira etapa consistiu de um estudo qualitativo, do tipo exploratório, através da realização de grupos focais com os técnicos de enfermagem e enfermeiros das unidades que possuem dispensários eletrônicos. Na segunda etapa foi realizado um estudo metodológico para tradução e validação do instrumento ISMP Medication Safety Self Assessment® for Automated Dispensing Cabinets através da realização das etapas de tradução por dois tradutores independentes, síntese das traduções, retrotradução, síntese da retrotradução, avaliação por especialistas e pré-teste. Resultados: Durante a realização dos grupos focais a equipe de enfermagem demonstrou estar satisfeita com o uso dos dispensários eletrônicos, necessitando de algumas adequações e melhorias no processo. As etapas de adaptação transcultural do instrumento foram realizadas obtendo-se um instrumento adaptado para a realidade brasileira que pode auxiliar no planejamento da implantação de dispensários eletrônicos. Faz-se necessária a realização de validação externa deste instrumento para utilização na realidade nacional. Conclusões: Neste estudo ficou evidente a satisfação dos usuários dos dispensários eletrônicos com o uso destes equipamentos e a importância de um planejamento adequado para a implantação de novas tecnologias. Demonstra-se a importância de um trabalho conjunto entre as equipes de farmácia e enfermagem na implantação e utilização de dispensários eletrônicos com foco na segurança do paciente. / Objectives: To know the satisfaction and perception of the user nursing staff of automated dispensing cabinets about this equipment and cross-culturally adapt the instrument ISMP Medication Safety Self Assessment® for Automated Dispensing Cabinets for the Brazilian reality. Methods: The study was conducted in two stages. The first stage consisted of a qualitative study, exploratory, by conducting focus groups with nursing technicians and nurses of the units that use automated dispensing cabinets. In the second stage it was carried out a methodological study for the translation and validation of the instrument ISMP Medication Safety Self Assessment® for Automated Dispensing Cabinets by performing the translation stages by two independent translators, synthesis of translations, back translation, synthesis of back translation, evaluation by experts and pretest. Results: During the course of the focus groups the nursing staff proved to be satisfied with the use of automated dispensing cabinets, requiring some adjustments and improvements in the process. The steps of cross-cultural adaptation of the instrument were carried out obtaining a tool that can assist in planning the implementation of automated dispensing cabinets adapted to the Brazilian reality. Conducting external validation of this instrument for use at the national reality is necessary. Conclusions: In this study it was evident the satisfaction of users of automated dispensing cabinets with the use of this equipment and the importance of proper planning for the deployment of new technologies. It demonstrates the importance of joint work between the pharmacy and nursing staff in the implementation and use of automated dispensing cabinets with a focus on patient safety.

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