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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.
111

Metodologia para projeto de sistemas de medição confiáveis para estimação de estado considerando custo, medidas convencionais, fasoriais sincronizadas e índice UI via Algoritmo Evolutivo e Matriz HΔt / Reliable metering system plan for state estimation considering cost, conventional, synchronized phasor measurements and index UI via Evolutionary Algorithm and HΔt matrix

Bozz, Alex Andrius Cecchim 16 May 2014 (has links)
Esta dissertação trata do problema de projeto e fortalecimento de sistemas de medição, para efeito de estimação de estado em sistemas elétricos de potência. São dois os objetivos principais desta dissertação. O primeiro é o desenvolvimento e implementação, em computador, de uma metodologia para projeto e fortalecimento de sistemas de medição confiáveis que fazem uso de medidas convencionais obtidas pelo sistema SCADA e de medidas fasoriais sincronizadas. Haja vista a existência de medidas redundantes que apresentam a característica de não refletirem grande parcela de seus erros nos resíduos do estimador por mínimos quadrados ponderados, definidas em (BENEDITO et al., 2013) como medidas com elevado índice UI, o segundo objetivo desta dissertação é o desenvolvimento e implantação, em computador, de uma metodologia para projeto e fortalecimento de sistemas de medição confiáveis que, além de considerar os critérios técnicos de confiabilidade para efeito de estimação de estado, considere também o índice UI das medidas. A metodologia possibilita a obtenção de sistemas de medição confiáveis formados por medidas com índice UI baixo. Para o desenvolvimento das metodologias propostas são utilizados como base algoritmo evolutivo monobjetivo e o método para projeto de sistemas de medição que faz uso da chamada matriz HΔT, que é obtida via um processo de fatoração triangular da matriz jacobiana transposta do estimador de estado por mínimos quadrados ponderados. / This thesis focuses on the problem of metering system planning for state estimation purposes and has two main objectives. The first one is to develop a methodology for metering system planning that allows the project of reliable metering systems considering both conventional and synchronized phasor measurements. Because of the existence of redundant measurements that have the characteristics of not reflecting their errors into the residuals of the weighted least squares estimator, called in (BENEDITO et al., 2013) as measurements with high Undetectability Index (UI), the second objective of this thesis is to develop a methodology, for metering system planning, that allow the project of reliable metering systems formed by measurements with UI lower than a pre-specified value. The background to develop the proposed methodologies are evolutionary algorithms and the method to metering system planning based on the analysis of the HΔt matrix, that is obtained from the triangular factorization of the transpose Jacobian matrix of the weighted least squares estimator.
112

Varmvatten i flerbostadshus : Erfarenhet, kunskap och mätning för en klokare användning

Ek, Christian, Nilsson, Daniel January 2011 (has links)
Det pågår idag arbete på många håll för att göra våra bostäder mer energieffektiva, ofta genom tekniska förbättringar av till exempel klimatskärm och värmesystem. En post i energianvändningen som inte alltid får lika mycket fokus är varmvattenanvändningen. Varmvattenanvändningen mäts sällan i flerbostadshus, vilket gör att kunskapen kring den är relativt låg. På senare år har dock allt fler bostadsbolag börjat arbeta för att minska vattenanvändningen och en metod som har blivit allt vanligare är individuell mätning och debitering. I denna rapport redovisas ett examensarbete kring olika aspekter på vattenanvändning i flerbostadshus. Vattenanvändningen i ett bostadsbolag som överväger att införa individuell mätning och debitering undersöktes och jämfördes med statistik från ca 2000 lägenheter i två bostadsbolag som redan infört individuell mätning. Resultaten visar att användningen i allmänhet är lägre i fastigheter med individuell mätning, men också att användningen varierar stort, framförallt mellan olika lägenheter. Det finns också stor variation i hur stor andel av den totala användningen som är varmvatten, men resultaten tyder på att 40% är ett bättre antagande än de 30% som ofta används som schablonvärde. För att ge en bild över vattenanvändningen i svenska flerbostadshus och hur den utvecklats genom åren sammanställdes också statistik från vattenmätningar i olika undersökningar från de senaste 60 åren. Resultatet visar att variationen är stor, men att användningen per person varken är högre eller lägre nu än på 1950-talet. En möjlig utveckling är att användningen tidigare stigit, men sedan vänt nedåt igen. Per lägenhet och per kvadratmeter finns det dock en tydligare minskning, sannolikt på grund av minskande boendetäthet. Detta illustrerar en problematik i analyser av vattenanvändning: nyckeltalet måste väljas med omsorg. Sammanställningen visade också att intresset för att följa upp vattenanvändningen verkar ha varierat och att mätningar gjorts främst under tre perioder. I studien sammanställdes även vilken effekt införande av individuell mätning och debitering haft i olika undersökningar. Tydligt är att effekten varierar beroende på förutsättningarna i olika fastigheter, men en minskning av varmvattenanvändningen med 15-40% bör kunna förväntas. Med hjälp av boendestatistik undersöktes också olika variablers inverkan på vattenanvändningen. Endast en mindre del av variationen i vattenanvändning mellan olika fastigheter kunde förklaras med variabler som ålder och inkomstnivå. Viss ökad användning för åldersgrupperna 16-19 och 45-54 år kunde ses. Andra resultat var att vattenanvändningen minskar något med ökad andel lokalyta, medan fastigheternas byggår inte påverkar användningen. Individuella variationer och skillnader i beteende och vanor hos de boende är dock sannolikt de viktigaste förklaringarna till variation i vattenanvändning. En huvudslutsats i studien är att vattenanvändningen varierar stort mellan olika användare, och det kan vara svårt att förklara varför användningen är högre i vissa fastigheter och lägre i andra. Inte bara den totala vattenanvändningen utan också andelen som blir varmvatten varierar, vilket gör att det finns ett behov av att mäta även varmvattenanvändningen i de fall detta inte görs. Kollektiv varmvattenmätning skulle också ge bättre underlag för beslut om att införa individuell mätning och debitering – och för uppföljning av resultatet. / As multi-family houses get more energy efficient thanks to technical improvements of for example the building envelope and heating system, domestic hot water becomes an increasingly important part of the overall energy performance. Despite this fact, water use does not always get much attention, and in Sweden it is not common practice to measure the amount of hot water used in multi-family houses. In recent years, more and more housing companies have realized that there is a potential for improving the energy performance further by reducing the use of hot water. One increasingly popular method for this is individual metering – which is common in other countries but not the established practice in Sweden. This thesis deals with various aspects of water use in multi-family houses. Water use in a housing company considering to introduce individual metering was analyzed and compared with data from approximately 2000 flats in two other housing companies, which had already introduced individual metering. The results show that water use is generally lower in houses with individual metering, but that there is a considerable variation, particularly when studying water use in individual flats. There is also a large variation in the proportions between hot and cold water, but 40% hot water seems to be a better estimate than 30%, which is a commonly used value. Data on water use from other studies, covering the last sixty years, was also collected, in order to give an overview of water use in Swedish multi-family houses. The data shows great variation, and neither a significant increase nor decrease in water use per capita can be seen. One possible scenario is that water use per capita has previously increased, but then turned to a decrease. When measured as water use per square meter of living area or per flat there has been a significant reduction, mainly due to a gradually decreasing housing density. This illustrates a problem when analyzing water use: care must be taken when choosing which unit to use when comparing different data. Another result is that studies of water use in Swedish multi-family houses mainly appear in three periods, showing that there has been a varying interest in water use and its impact on energy performance. Data from other studies of individual metering was also collected, showing that the effect varies between different projects and houses, but that an expected result might be a reduction of hot water use by 15-40%. The thesis also includes an analysis of to what degree variation in water use can be explained by factors such as age and income levels. The variables available in the data could only explain part of the variation in water use, but some impact could be seen, e.g. that people in the ages of 16-19 and 45-54 years seem to use more water than others. However, most of the variation in water use is probably caused by different users’ individual behaviour and habits. One important conclusion is that there is a large variation in water use, and that it is difficult to explain why water use is high in some houses and low in some. Not only does the total water use vary, but also the proportions between hot and cold water. With this in mind, installing hot water meters would be beneficial for many housing companies, not only giving better data on energy performance but also as a first step before introducing individual metering.
113

Adaptive fuzzy systems for traffic responsive and coordinated ramp metering /

Bogenberger, Klaus. January 1900 (has links)
Originally presented as the author's Thesis (doctoral)--Technische Universität München. / "FGV-TUM." Includes bibliographical references (p. 147-156).
114

SMART GRID COMMUNICATIONS

Asbery, Christopher W 01 January 2012 (has links)
Smart grid technologies are starting to be the future of electric power systems. These systems are giving the utilities detailed information about their systems in real time. One of the most challenging things of implementing smart grid applications is employing the communications into the systems. Understanding the available communications can help ease the transition to these smart grid applications. Many of the utility personnel are spending too much time trying to figure out which communication is better for their application or applications. So this thesis presents the different communication types available with discussing the different attributes in which these communication types are going to offer to the utility. Then these communication types are looked such that utilities can quickly understand how to approach the difficult task of obtaining the information from the different smart grid applications by the use of different communication options.
115

Adaptive fuzzy systems for traffic responsive and coordinated ramp metering

Bogenberger, Klaus. January 1900 (has links)
Originally presented as the author's Thesis (doctoral)--Technische Universität München. / "FGV-TUM." Includes bibliographical references (p. 147-156).
116

Detection of Back-Fed Ground Faults Using Smart Grid Distribution Technology

January 2014 (has links)
abstract: The safety issue in an electrical power distribution system is of critical importance. In some circumstances, even the continuity of service has to be compromised for a situation that can cause a hazard to the public. A downed conductor that creates an electrical path between a current carrying conductor and ground pose a potential lethal hazard to anyone in the near proximity. Electric utilities have yet to find a fully accepted and reliable method for detecting downed conductors even with decades of research. With the entry of more automation and a smarter grid in the different layers of distribution power system supply, new doors are being opened and new feasible solutions are waiting to be explored. The 'big data' and the infrastructures that are readily accessible through the smart metering system is the base of the work and analysis performed in this thesis. In effect, the new technologies and new solutions are an artifact of the Smart Grid effort which has now reached worldwide dimensions. A solution to problems of overhead distribution conductor failures / faults that use simple methods and that are easy to implement using existing and future distribution management systems is presented. A European type distribution system using three phase supply is utilized as the test bed for the concepts presented. Fault analysis is performed on the primary and the secondary distribution system using the free downloadable software OpenDSS. The outcome is a set of rules that can be implemented either locally or central using a voltage based method. Utilized in the distribution management systems the operators will be given a powerful tool to make the correct action when a situation occurs. The test bed itself is taken from an actual system in Norway. / Dissertation/Thesis / Masters Thesis Electrical Engineering 2014
117

Reconciling Consumer and Utility Objectives in the Residential Solar PV Market

January 2014 (has links)
abstract: Today's energy market is facing large-scale changes that will affect all market players. Near the top of that list is the rapid deployment of residential solar photovoltaic (PV) systems. Yet that growing trend will be influenced multiple competing interests between various stakeholders, namely the utility, consumers and technology provides. This study provides a series of analyses--utility-side, consumer-side, and combined analyses--to understand and evaluate the effect of increases in residential solar PV market penetration. Three urban regions have been selected as study locations--Chicago, Phoenix, Seattle--with simulated load data and solar insolation data at each locality. Various time-of-use pricing schedules are investigated, and the effect of net metering is evaluated to determine the optimal capacity of solar PV and battery storage in a typical residential home. The net residential load profile is scaled to assess system-wide technical and economic figures of merit for the utility with an emphasis on intraday load profiles, ramp rates and electricity sales with increasing solar PV penetration. The combined analysis evaluates the least-cost solar PV system for the consumer and models the associated system-wide effects on the electric grid. Utility revenue was found to drop by 1.2% for every percent PV penetration increase, net metering on a monthly or annual basis improved the cost-effectiveness of solar PV but not battery storage, the removal of net metering policy and usage of an improved the cost-effectiveness of battery storage and increases in solar PV penetration reduced the system load factor. As expected, Phoenix had the most favorable economic scenario for residential solar PV, primarily due to high solar insolation. The study location--solar insolation and load profile--was also found to affect the time of year at which the largest net negative system load was realized. / Dissertation/Thesis / Masters Thesis Engineering 2014
118

Potencial inclusivo da energia solar: análise dos aspectos jurídicos

Oliveira, Thais Paranhos Mariz de 19 February 2018 (has links)
Submitted by Hernani Medola (hernani.medola@mackenzie.br) on 2018-03-21T23:32:51Z No. of bitstreams: 2 Thais Paranhos Mariz de Oliveira.pdf: 1256756 bytes, checksum: 407ab34292370a5f646994c8e575d1e4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Paola Damato (repositorio@mackenzie.br) on 2018-04-04T11:46:47Z (GMT) No. of bitstreams: 2 Thais Paranhos Mariz de Oliveira.pdf: 1256756 bytes, checksum: 407ab34292370a5f646994c8e575d1e4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2018-04-04T11:46:47Z (GMT). No. of bitstreams: 2 Thais Paranhos Mariz de Oliveira.pdf: 1256756 bytes, checksum: 407ab34292370a5f646994c8e575d1e4 (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2018-02-19 / Distributed generation of electricity from photovoltaic solar systems has become a worldwide trend. Although many countries have implemented policies to encourage consumer participation in the generation of electricity through photovoltaic panels, Brazil still needs to consolidate a policy in this direction. The objective of this study is to investigate whether the use of photovoltaic solar energy, through distributed generation, increases access to electric energy, promoting social inclusion both for communities that are not supplied with electricity and for society in general. Also, to explore the role of public policies in promoting solar energy and social inclusion by reducing electricity expenditure, promoting citizen participation in energy production processes and guaranteeing safe, reliable, modern access and electricity to all. In order to reach its objectives, bibliographic review pertinent to the theme and analysis of the legal norms adopted in the three spheres of the Federation, notably Normative Resolution No. 482, published by the National Agency of Electric Energy - ANEEL, in the year of 2012 to the citizen to generate the energy for your own consumption have been done. As an example of public policies about solar energy, and for a better understanding of the two incentive mechanisms used in the world, German and Californian policies were analysed: feed-in tariff and net metering, respectively. The comparison between models suggest that net metering is the most appropriate regulatory framework for Brazil, and showed the importance of adopting an incentive model for the acquisition of photovoltaic panels, as well. / A disseminação da geração distribuída de eletricidade, a partir da energia solar fotovoltaica, tem se mostrado uma tendência mundial. Embora muitos países tenham implementado políticas públicas de incentivo à participação do consumidor na geração de eletricidade por meio de painéis fotovoltaicos, o Brasil ainda precisa consolidar uma política nesse sentido. O presente trabalho teve por objetivo investigar se o emprego da energia solar fotovoltaica, por meio da geração distribuída, tem o condão de ampliar o acesso à energia elétrica, promovendo inclusão social tanto para as comunidades desprovidas do fornecimento de energia elétrica como para a sociedade em geral. Especificamente, questiona-se o papel de políticas públicas de promoção da energia solar na busca por maior inclusão social, promovendo redução no valor de contas de luz, a participação dos cidadãos nos processos de produção energética e o acesso seguro, confiável, moderno e a preços módicos à eletricidade a todas e todos. Para tanto, foi utilizada revisão bibliográfica pertinente ao tema e análise das normas jurídicas adotadas nas três esferas da Federação, notadamente da Resolução Normativa nº 482, editada pela Agência Nacional de Energia Elétrica – ANEEL, no ano de 2012, que trouxe ao Brasil a possibilidade ao cidadão de gerar a energia elétrica para consumo próprio. A título ilustrativo, e para uma melhor compreensão dos dois mecanismos de incentivo existentes hoje no mundo para a geração distribuída a partir da energia solar fotovoltaica, foram analisados os modelos utilizados na Alemanha e no Estado norte-americano da Califórnia: feed-in tariff e net metering, respectivamente. A comparação entre eles reforça a importância na adoção do segundo modelo como marco regulatório no Brasil, bem como na promoção de um modelo de incentivo à aquisição de painéis fotovoltaicos, notadamente nas comunidades dos sistemas isolados.
119

Smart metering / Smart metering

Lahodný, Libor January 2016 (has links)
Semester paper describes the design of smart sockets and their management. Sockets are wirelessly controlled by a central unit. The socket has an integrated sensor, designed to measure current consumption of the device. If necessary, it can remotely disconnect the unit plugged in socket from AC network. Work includes analysis of individual system elements, design of electrical schematics and PCB. In the construction is included ethernet module, which is used to display data using a computer.. The device has been constructed and tested.
120

Analýza využití funkce breaker/limiter u odběrných míst nízkého napětí / Analyses of the breaker/limiter functions for low voltage supply points

Bajánková, Denisa January 2017 (has links)
The diploma thesis provides an insight into the remote control and disconnection of DSO supply points phenomenon. The remote or local disconnection/connection of supply point is allowed by the breaker function. The automatic disconnection of supply point is enabled by the limiter function. Due to the anticipated implementation of smart meters in the Czech Republic in the future, this work contains the comprehensive description of breaker/limiter function with proposed possibilities of use in the Czech Republic. The thesis deals with the current breaker/limiter function use in the Czech Republic and in other countries. It introduces the smart meter installation in pilot projects to analyze the breaker/limiter function use in other countries. The thesis is focused on the technical solution of breaker/limiter. Moreover, it describes the ways of connecting the breaker, settting the limiter, connecting/disconnecting a supply point and breaker operation. Further, the thesis introduces the ways of activating the breaker by a customer and defines in which cases it is possible to limit and interrupt the electricity supply in the Czech Republic currently. The main aim of thesis is to describe the specific possibilities of breaker/limiter function use in the Czech Republic. With regard to the function use in other countries and the limiting or interrupting the electricity supply by DSO according to energy law, the possibilities of use are proposed. Each possibility of use is analyzed when implementing the breaker function or the breaker/limiter function. The benefits are defined for a DSO and for a customer. The proposed uses are evaluated in terms of applicability and valid legislation in the Czech Republic. The result of this work is the summary of information about breaker/limiter function which is one of the new features in the implementation of smart metering. The function installation and the implementation of possibilities described in the thesis depends on the DSO decision.

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