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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

Detecção de eventos para monitoração de qualidade de energia elétrica por medidores de faturamento usando a Transformada Wavelet e a Norma Euclidiana Instantânea. / Detection of events for monitoring the quality of billing electronic meters by using Wavelet Transform and the Instantaneous Euclidian Norm.

Francisco Pereira Júnior 14 April 2009 (has links)
Este trabalho estuda a possibilidade de se adicionar funções de detecção e registro de eventos, que afetam a qualidade de energia elétrica, aos medidores eletrônicos de faturamento. A presença destes medidores na grande maioria dos consumidores ligados à média tensão transforma este recurso em uma poderosa ferramenta de análise. A existência de canais de comunicação remota nestes medidores facilita a coleta dos dados e seu armazenamento. Estes dados transferidos para sistemas com alta capacidade de processamento permitem uma análise mais precisa dos eventos que ocorrem em toda a rede. Foram consideradas as limitações dos medidores de faturamento quanto à sua capacidade de processamento, memória e taxa de amostragem. Os eventos que podem ser detectados com estes medidores ficam restritos a variações de tensão de curta duração (VTCDs) e transitórios oscilatórios de baixa freqüência. As funções criadas para registro de eventos podem ser usadas para registro de sinais em regime permanente, aumentando a capacidade de diagnóstico e análise da qualidade da energia elétrica em locais da rede. São utilizadas como técnicas de detecção de eventos: as variações dos valores eficazes, a decomposição de sinais, a Norma Euclidiana Instantânea (NEI) e a transformada wavelet (TW). / This work shows the possibility to add new functions for detection and registration of disturbances that affect power quality to electronic billing meters. The widespread installation of these meters in the power network makes this resource a powerful analysis tool. Remote communication channels in these meters create an easy way for reading and registering such power quality events. Data transferred to powerful processing systems allow accurate analysis of events occurring in the power grid. The limitations on billing meters, namely processing resources, memory availability and sampling rate, were taken into account. Despite these limitations, the electronic meters can handle short duration voltage events and low-frequency oscillatory transients. Those new functions can also be used for registering steady state phenomena, extending the ability to diagnose power quality problems throughout the power network. Techniques like RMS variations, signal decomposition, instantaneous Euclidian norm and wavelet transform were used for detection of the considered power quality events.
102

Detecção de eventos para monitoração de qualidade de energia elétrica por medidores de faturamento usando a Transformada Wavelet e a Norma Euclidiana Instantânea. / Detection of events for monitoring the quality of billing electronic meters by using Wavelet Transform and the Instantaneous Euclidian Norm.

Pereira Júnior, Francisco 14 April 2009 (has links)
Este trabalho estuda a possibilidade de se adicionar funções de detecção e registro de eventos, que afetam a qualidade de energia elétrica, aos medidores eletrônicos de faturamento. A presença destes medidores na grande maioria dos consumidores ligados à média tensão transforma este recurso em uma poderosa ferramenta de análise. A existência de canais de comunicação remota nestes medidores facilita a coleta dos dados e seu armazenamento. Estes dados transferidos para sistemas com alta capacidade de processamento permitem uma análise mais precisa dos eventos que ocorrem em toda a rede. Foram consideradas as limitações dos medidores de faturamento quanto à sua capacidade de processamento, memória e taxa de amostragem. Os eventos que podem ser detectados com estes medidores ficam restritos a variações de tensão de curta duração (VTCDs) e transitórios oscilatórios de baixa freqüência. As funções criadas para registro de eventos podem ser usadas para registro de sinais em regime permanente, aumentando a capacidade de diagnóstico e análise da qualidade da energia elétrica em locais da rede. São utilizadas como técnicas de detecção de eventos: as variações dos valores eficazes, a decomposição de sinais, a Norma Euclidiana Instantânea (NEI) e a transformada wavelet (TW). / This work shows the possibility to add new functions for detection and registration of disturbances that affect power quality to electronic billing meters. The widespread installation of these meters in the power network makes this resource a powerful analysis tool. Remote communication channels in these meters create an easy way for reading and registering such power quality events. Data transferred to powerful processing systems allow accurate analysis of events occurring in the power grid. The limitations on billing meters, namely processing resources, memory availability and sampling rate, were taken into account. Despite these limitations, the electronic meters can handle short duration voltage events and low-frequency oscillatory transients. Those new functions can also be used for registering steady state phenomena, extending the ability to diagnose power quality problems throughout the power network. Techniques like RMS variations, signal decomposition, instantaneous Euclidian norm and wavelet transform were used for detection of the considered power quality events.
103

The application of Doppler velocity meters in the measurement of open channel discharges

Gunther, U. K. (Uwe Karsten) 12 1900 (has links)
Thesis (MEng)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: This report deals with the use of Doppler meters to measure flow velocities and hence discharges in streams. The Doppler meter measures the shift in frequency of an acoustic wave, which it emits and then becomes reflected by a moving particle. The reading is converted into a velocity by dividing the shifted frequency by a calibration constant. The particles that reflect the signal need to follow the flow sufficiently closely so that their velocity may be assumed equal to the flow velocity. A previous study on the use of the Doppler meter at a Crump weir (Du Toit and Venter, 1999) indicated that velocities measured with a Doppler meter showed a distinct relationship with recorded water levels. However, the wide scatter of the observed frequencies in this study, necessitated further tests on the use of the Doppler meter at measuring structures as well as calibration tests on the instrument in the hydraulic laboratory of the University of Stellenbosch. The mam objective of this investigation was to establish the relationship between measured Doppler velocities at a Crump weir and the approach velocities in the stream. The instrument was to be tested in both modular and non-modular flow ranges. In addition, the instrument had to be calibrated in the hydraulic laboratory under varying flow conditions, such as very low flow velocities and different sediment concentrations. The placement of the probe at different depths of the flow was also investigated to comment on the accuracy of the Doppler readings at these depths. The results of these tests should serve as guidelines for any additional tests required for use of this instrument in open channel discharge measurements. The Doppler meter used for this study was supplied and manufactured in Stellenbosch by Flotron, and is being marketed as DFM-P-067. It was calibrated in the laboratory in a channel with limited width and hence non-two-dimensional flow conditions. Conclusions were drawn on the calibration constant that was established. The calibration of the instrument requires the division of the cross-sectional flow area into a number of sub-divisions over which the flow was integrated. The calibration constant of 1460 established in this study differs by approximately 6 percent from the theoretical constant value of 1375. The sensitivity of the Doppler meter to different sediment concentrations was also investigated. For the instrument to read a shifted frequency, it is essential that suspended particles that follow the water movement sufficiently closely are present in the stream. It was observed that readings of the instrument in "sediment-free" water differed only by 3.6% from the readings taken in water containing sediments. The instrument was thus not very sensitive to different sediment concentrations. It was also found that the angle at which the probe was placed in the water had no effect on the accuracy of the observed Doppler velocity. It was furthermore found that the Doppler meter worked reliably at all depths, including levels very close to the channel floor and levels just below the water surface. One drawback of the apparatus was the minimum velocity that it can measure accurately. This minimum velocity of 0.046 mis does not compare well with that for other commercially available Doppler meters. The Argonaut-Acoustic Doppler meter for example can measure velocities as low as O.OOOlm/s, meaning that the DFM-P-067 measures a minimum velocity 460 times swifter than the minimum velocity of the Argonaut-Acoustic Doppler meter. After the Doppler meter had been calibrated, it was tested at a Crump weir in the laboratory to determine the relationship between the Doppler velocities, measured at the weir's crest, and the velocities in the approach channel. These tests were performed for both modular and non-modular flow conditions. The report concludes that, within the flow range in which the instrument was tested, there is a linear relationship between the two velocities mentioned. It is likely that the results obtained in the modular flow range can be used to extrapolate for high flows, especially for submergence ratios less than 0.93. The wide scatter of results obtained in the previous study was due to the readings not being averaged. The Doppler meter does not measure a point velocity but an average velocity within the acoustic field that it emits. This acoustic field is very small and depends on the geometry of the probe. Finally it is recommended that the linear relationship in the non-modular flow range be investigated further in a larger model, where the submergence ratio can be better controlled. The Doppler meter should in future also be calibrated in a wide channel in which two-dimensional flow conditions are approached and these results should be compared to the results obtained in this study. Every instrument is expected to have its own calibration constant, and depending on its application, it can either be calibrated at a weir or in the laboratory. The calibration of the instrument at a Crump weir should allow for a wider range of flows, and also very low flow velocities. At the end of this report guidelines were drawn up that are based on the results and conclusions obtained in this investigation. They may serve as an aid for measurements that could be carried out with this instrument in open channels. / AFRIKAANSE OPSOMMING: Hierdie verslag handeloor die gebruik van die Doppler-meter om vloeisnelhede en derhalwe die vloeitempos in riviere te meet. Die Doppler meter word gebruik om die verandering in die frekwensie van 'n akoustiese golf wat deur bewegende deeltjies in die water gereflekteer word te meet. Die lesing word dan omgeskakel in 'n snelheid deur die gewysigde frekwensie deur 'n kalibrasie konstante te deel. Die bewegende deeltjies wat die sein reflekteer, volg die vloei genoegsaam sodat aanvaar kan word dat hulle snelhede gelyk aan die vloeisnelheid is. 'n Vorige studie in die gebruik van die Doppler meter by 'n Crump meetwal het baie belowende resultate getoon deurdat daar gevind is dat die gemete Doppler snelheid 'n duidelike verwantskap toon met veranderings in gemete water vlakke. As gevolg van die wye band in die waargenome frekwensies in die studie is aanbeveel dat verdere toetse op die gebruik van die Doppler meter by meetstasies gedoen moet word. Die instrument moet ook in die laboratorium gekalibreer word. Die hoofdoel van hierdie ondersoek was om die verwantskap tussen die gemete Doppler snelhede by 'n Crump meetwal en die aankomssnelhede in die stroom te bepaal. Dit moes gedoen word in beide die modulêre en niemodulêre vloeibestekke. Behalwe vir die kalibrasie van die instrument in die laboratorium moes die betroubaarheid daarvan onder verskillende vloei toestande ook getoets word, soos byvoorbeeld by lae vloei snelhede en by verskillende sediment konsentrasies. Die instrument is ook op verskillende vlakke binne die vloei getoets om te bepaal of daar op hierdie vlakke betroubare lesings verwag kon word. Resultate verkry, kan dan dien as riglyne vir enige verdere toetse wat nog op die instrument in oop kanale uitgevoer moet word. Die Doppler meter wat vir die ondersoek gebruik is, word in Stellenbosch vervaardig deur Flotron en word onder die naam DFM-P-067 bemark. Dit is in die laboratorium in 'n kanaal met 'n beperkte breedte getoets en IS daarom in nie-twee dimensionele vloei gekalibreer. Gevolgtrekkings IS gebaseer op die kalibrasie konstante verkry uit die toetse. Die kalibrasie van die instrument vereis dat die deursnee area van die vloei in verskeie segmente onderverdeel moes word. Die kalibrasie konstante van 1460 bepaal in hierdie studie verskilongeveer 6% van die teoretiese waarde van 1375 vir die konstante. Die Doppler meter se sensitiwiteit vir verskillende sediment konsentrasies is ook ondersoek. Dit is noodsaaklik dat daar gesuspendeerde deeltjies teenwoordig in die water is en dat die deeltjies saam met die water beweeg om te verseker dat die instrument die gewysigde frekwensie kan registreer. Daar is egter gevind dat die lesings van die instrument in sediment-vrye water slegs met 3,6% verskil van lesings wat in water met sediment geneem is. Dit lei tot die gevolgtrekking dat die instrument nie baie sensitief vir veranderlike sediment konsentrasies in die water is nie. Daar is ook gevind dat die hoek waarteen die sender in die water geplaas word nie die akkuraatheid van die Doppler snelhede beinvloed nie. Verder is gevind dat die Doppler meter bevredigende resultate lewer, ongeag op watter diepte lesings geneem word. Tydens toetse is waarnemings baie nabyaan die kanaal bodem asook nabyaan die water se oppervlak gedoen. 'n Tekortkoming van hierdie instrument is die minimum snelheid wat dit akkuraat kan meet. Daar is gevind dat die Doppler meter se muurnum snelheid lesing van 0.046 mis nie goed vergelyk met dié van ander meters wat kommersieël beskikbaar is nie. Die Argonaut-Acoustic Doppler meter kan byvoorbeeld vloeisnelhede so laag as 0.0001 mis meet wat beteken dat die DFM-P-067 se minimum betroubare vloeisnelheid 460 keer vinniger is as die Argonaut-Acoustic Doppler meter se minimum betroubare vloeisnelheid. Nadat die Doppler meter gekalibreer is, is dit by 'n Crump meetwal in die laboratorium getoets om die verhouding tussen die Doppler snelhede gemeet by die oorloopkruin en die snelhede wat in die aanloopkanaal gemeet is, te bepaal. Hierdie toetse is uitgevoer op beide modulêre en nie-modulêre vloei toestande. Daar is gevind dat daar binne die vloeibestek waarin die toetse plaasgevind het 'n liniêere verband tussen die twee bogenoemde snelhede bestaan. Dit is hoogs waarskynlik dat die resultate wat in die modulêre vloeibestek gevind is gebruik kan word om vir hoë vloeie te ekstrapoleer, veral vir grade van versuiping laer as 0.93. Die vorige studie se uiteenlopende resultate kan toegeskryf word aan lesings waarvan die gemiddelde lesing vir 'n spesifieke vloeitoestand nie bepaal is nie. Die Doppler meter meet nie 'n bepaalde punt-snelheid nie, maar 'n gemiddelde snelheid binne die akoestiese veld wat dit uitstraal. Hierdie akoestiese veld is baie klein en afhanklik van die geometrie van die sender. Ten slotte word aanbeveel dat die lineêre verband in die nie-modulêre vloeibestek in 'n groter model, waar die graad van versuiping makliker beheerbaar is, verder ondersoek moet word. Die Doppler meter moet ook in 'n breë kanaal waarin twee dimensionale vloei voorkom, gekalibreer word. Resultate so verkry moet vergelyk word met die wat in hierdie studie behaal is. Elke instrument behoort sy eie kalibrasie konstante te hê en afhangende van waar dit gebruik word, kan dit of by 'n meetwal of in die laboratorium gekalibreer word. Die kalibrasie van die instrument by 'n Crump meetwal behoort 'n wyer reeks vloeie toe te laat met ook baie lae snelhede. Die verslag word afgesluit met riglyne gebaseer op die resultate en gevolgtrekkings wat uit die ondersoek voortgespruit het. Hierdie riglyne en gevolgtrekkings kan dan dien as 'n hulpmiddel vir metings wat met hierdie instrument in oop kanale uitgevoer word.
104

Pre-paid water metering: social experiences and lessons learned from Klipheuwel pilot project, South Africa.

Kumwenda, Moses January 2006 (has links)
<p>This thesis examined a pre-paid water metering pilot project which was implemented in Klipheuwel , Cape Town, South Africa in 2001. It was anticipated that the implementation of pre-paid water meters would help improve the management of water service delivery in the Cape Metropolitan Area. However, just four years after its implementation the project has collapsed.</p>
105

Desempenho de jovens nadadores na distância de 100 metros nado crawl / Performance of young swimmers in 100 meters front crawl

Vitor, Fabrício de Mello 03 September 2008 (has links)
O presente estudo teve como objetivos descrever aspectos antropométricos, de aptidão física específica e, técnicos de nado; verificar as relações existentes entre idade cronológica, antropometria, aptidão física específica e técnica de nado com o desempenho na distância de 100 metros nado Crawl e verificar a influência das variáveis antropométricas, de aptidão física específica e, técnicas de nado sobre o desempenho de jovens nadadores na distância de 100 metros Nado Crawl. Participaram do estudo 24 nadadores púberes do sexo masculino com idade de 13,0 ± 0,7 anos. A análise de regressão múltipla (método forward) foi realizada com o propósito de explicar a variabilidade da velocidade obtida nos 100 metros Nado Crawl. Velocidade média da potência anaeróbia (r² = 0,67), índice de eficiência de nado (r² = 0,62) e velocidade crítica (r² = 0,34) explicaram em 88% a variabilidade da velocidade obtida nos 100 metros nado Crawl. O modelo de regressão estatístico foi significante ao nível de 0,05 e o erro padrão de estimativa foi de 0,03. O custo energético da prova de 100 metros Nado Crawl tem papel relevante no maior peso preditivo da potência anaeróbia assim como, a inclusão da velocidade crítica (resistência aeróbia) no modelo de regressão. Quanto ao índice de eficiência de nado, é possível assegurar que, a aplicação efetiva da força contra a água é o fator determinante da economia de movimento nesta atividade, ou seja, quanto melhor a técnica de nado, menos energia será gasta e melhor será o desempenho final / The purposes of this study were to describe: anthropometric aspects, specific physical fitness and stroking parameters; to verify relationship between anthropometric, specific physical fitness, stroking parameters and 100 meters front Crawl and to verify influence of anthropometry, specific physical fitness and stroking parameters variables over performance in 100 meters front Crawl in young swimmers. The group was composed by 24 pubertal males with 13,0 ± 0,7 years-old. Multiple regression analysis (forward method) was used to explain variance of 100 meters front Crawl velocity. Anaerobic power velocity (r² = 0,67), swimming efficiency index (r² = 0,62) and critical velocity (r² = 0,34) explained 88% of variance 100 meters front Crawl in young male pubertal swimmers. Regression model was significantly at 0,05 level and, estimative error standard was 0,03. Energetic expenditure of 100 meters front crawl has a relevant importance in predictive value of anaerobic power and inclusion of critical velocity on regression. About swimming efficiency index, effectiveness of force against water is main reason for swimming economy and, as better swimming technique, less energy will be expended resulting in better performance
106

Determinação do teor de umidade em madeiras por meio de medidores elétricos / not available

Rodrigues, Waldemir 02 July 1999 (has links)
A madeira quando seca é um excelente isolante elétrico, porém quando a umidade da madeira aumenta, essa característica diminui fazendo com que esta passe a conduzir a corrente elétrica. A determinação do teor de umidade permite um controle do custo de produção e qualidade da madeira, além de facilitar a utilização de tratamentos preservativos e pintura. O método de determinação do teor de umidade com o uso de estufa é o método mais exato, e por esta razão é utilizado como padrão para calibrar outras técnicas. Por outro lado, a verificação do teor de umidade por meio da estufa é muito demorado e danifica parte do componente a ser analisado. O objetivo deste trabalho é propor uma metodologia para calibrar medidores elétricos de umidade, utilizando espécies de dicotiledôneas nativas e coníferas de florestamento. Na experimentação realizada foi possível constatar que apesar da menor precisão na determinação de teores de umidade, o método que utiliza medidores de umidade do tipo resistência, permite com algumas correções, a obtenção de valores confiáveis para o controle de umidade de peças de madeira serrada. Para isso foram desenvolvidas expressões obtidas por meio de análise de regressão linear que possibilitam fazer as correções necessárias nas leituras realizadas com o medidor elétrico do tipo resistência. / Wood when dry is an excellent electric insulating material. However when the moisture content of wood increases, that feature decreases, which makes it conduct electric current. Determining the moisture content allows the control of the production cost and the quality of the timber, and also facilitates the use of preservative treatments and painting. The method for the determination of the moisture content using the kiln is the most exact method, and therefore it is used as standard to calibrate other techniques. On the other hand, the verification of the moisture content by means of the kiln takes toe much time and damages part of the component to be analyzed. The aim of this work is to propose a methodology to gauge electric moisture meters using species of tropical and forestation hardwood and softwood. The experiments made it possible to verify that, even having less accuracy in determining the moisture content, the method based on moisture electric meters allows, with some adjustments, a reliable data acquisition for the control of moisture content of sawed lumber. For this matter, equations were developed by means of linear regression analysis allowing the necessary corrections of the readings carried out with the electric measurer of the resistance type.
107

Acoustic tracking of an unmanned underwater vehicle using a passive ultrashort baseline array and a single long baseline beacon

Unknown Date (has links)
This thesis discusses a new approach to tracking the REMUS 100 AUV using a modified version of the Florida Atlantic University (FAU) ultrashort baseline (USBL) acoustic positioning system (APS). The REMUS 100 is designed to utilize a long baseline (LBL) acoustic positioning system to obtain positioning data in mid-mission. If the placement of one of the transponders of the LBL field is known, then tracking the position of the REMUS 100 AUV using a passive USBL array is possible. As part of the research for this thesis, the FAU USBL system was used to find a relative range between the REMUS 100 ranger and a LBL transponder. This relative range was then combined with direction of arrival information and LBL field component position information to determine an absolute position of the REMUS 100 ranger. The outcome was the demonstration of a passive USBL based tracking system. / by Kyle L. Seaton. / Thesis (M.S.C.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
108

Leitura automatizada de medidores de consumo de energia elétrica eletromecânicos. / Automated reading of eletromechanical electric energy consumption meter.

Bizarria, José Walter Parquet 02 June 2006 (has links)
BIZARRIA, J. W. P. Leitura automatizada de medidores de consumo de energia elétrica eletromecânicos. 2006. 255 f. Tese (Doutorado) - Escola Politécnica, Universidade de São Paulo, São Paulo, 2006. Este trabalho aborda o projeto conceitual de um sistema voltado para a leitura automatizada de medidores de consumo de energia elétrica eletromecânicos, residenciais, com transdutores por indução acoplados a registradores mecânicos ciclométricos, sendo esse sistema denominado de Sistema Automatizado para Leitura de Medidores Eletromecânicos (SALME). Nessa abordagem, são explorados conceitos que visam contribuir para a evolução desse tipo de medidor e de outros, aos quais esses conceitos possam ser estendidos. Os elementos desse sistema oferecem contribuição voltada para a busca de soluções dos atuais problemas existentes, principalmente no que se refere à automatização dos processos de aquisição de dados do consumo de energia elétrica, e no combate às fraudes. O SALME está fundamentado numa arquitetura de sistema distribuído que separa o medidor em duas unidades: uma destinada para a medição do consumo; outra para a visualização dos dados referentes à leitura do medidor. O modelo de aplicação dessa arquitetura prevê a instalação da unidade de medição no âmbito da via pública, sendo a unidade de visualização instalada no âmbito da unidade consumidora. A instalação da unidade de medição no âmbito da via pública dificulta a implementação e utilização de circuitos não autorizados, que impeçam ou interfiram na medição dos corretos valores de consumo de energia elétrica, a serem utilizados para a cobrança desse insumo. A instalação da unidade de visualização no âmbito da unidade consumidora proporciona ao consumidor a leitura do medidor, prevista para esse tipo de aplicação. Nesse sistema, a leitura do medidor é automatizada, de forma que a aquisição dos dados de leitura dos consumos pode ser realizada no âmbito da via pública, por meio do uso de coletores de dados ou por interligação a sistemas de comunicação que utilizam redes de longa distância. Para a comunicação com os coletores de dados, é prevista a utilização da radiação infravermelha como meio de comunicação sem fio. A automatização da leitura dos medidores é fundamentada no conceito de leitura eletrônica do registrador mecânico ciclométrico, sendo exploradas abordagens que envolvem: a conversão optoeletrônica analógica; a aquisição e o processamento de imagens, e a conversão optoeletrônica digital. Os resultados obtidos nos ensaios práticos efetuados com os protótipos dos elementos do SALME foram satisfatórios, sendo validados os princípios de funcionamento desses elementos, ratificando os conceitos propostos, mostrando que os objetivos previstos neste trabalho foram alcançados em toda a sua plenitude. / BIZARRIA, J. W. P. Automated reading of electromechanical electric energy consumption meter. 2006. 255 f. Thesis (Doctoral) - Escola Politécnica, Universidade de São Paulo, São Paulo, 2006. This work embodies a conceptual design of a system focalized in automatic reading of electromechanical electric energy consumption meter, residential, with inductive transducers coupled together with cyclic mechanical registers, being that system called by Automated System for Reading of Electromechanical Meter (ASREM). On that approach are explored concepts that aim to contribute for evolution of that type of meter and others of which those concepts can be extended. The elements of that system offer contribution dedicated for the search of solutions of the current problems, mainly referring to automation of data acquisition processes of electric power consumption, and against to swindle. ASREM is based on architecture of distributed system that splits the meter into two units, being one destined to consumption measurement and other for visualization of the data related to the meter reading. The model of application of that architecture, foresees the installation of a measurement unit in the ambit of public electrical network, being the unit of visualization installed in the ambit of consumer demand. The installation of measurement unit in the ambit of public electrical network, obstructs the implementation and use of non authorized circuits that prevent or interfere in the measurement of correct values of electric power consumption to be utilized for the collection of that tariff. The installation of unit for visualization in the ambit of consumer demand, provides to the consumer the reading of the meter foreseen for that type of application. On that system the reading of the meter is automated, so that the acquisition of the reading data of the consumptions it can be accomplished in the ambit of public electrical network, by means of usage either by data collectors or by interconnection to communication systems that use long distance networks. For the communication with the data collectors that is forecasted the utilization of infrared radiation as a mean of wireless communication. The automation of meters reading is based on concept of electronic reading of the cyclic mechanical register, being explored approaches that involve: the analogical optoelectronic conversion, acquisition and image processing, and digital optoelectronic conversion. The results obtained in the practical tests performed with the prototypes of ASREM elements, were satisfactory, being validated the principles of operation of those elements, ratifying the proposed concepts, showing that the objectives foreseen in this work were fully reached.
109

Leitura automatizada de medidores de consumo de energia elétrica eletromecânicos. / Automated reading of eletromechanical electric energy consumption meter.

José Walter Parquet Bizarria 02 June 2006 (has links)
BIZARRIA, J. W. P. Leitura automatizada de medidores de consumo de energia elétrica eletromecânicos. 2006. 255 f. Tese (Doutorado) - Escola Politécnica, Universidade de São Paulo, São Paulo, 2006. Este trabalho aborda o projeto conceitual de um sistema voltado para a leitura automatizada de medidores de consumo de energia elétrica eletromecânicos, residenciais, com transdutores por indução acoplados a registradores mecânicos ciclométricos, sendo esse sistema denominado de Sistema Automatizado para Leitura de Medidores Eletromecânicos (SALME). Nessa abordagem, são explorados conceitos que visam contribuir para a evolução desse tipo de medidor e de outros, aos quais esses conceitos possam ser estendidos. Os elementos desse sistema oferecem contribuição voltada para a busca de soluções dos atuais problemas existentes, principalmente no que se refere à automatização dos processos de aquisição de dados do consumo de energia elétrica, e no combate às fraudes. O SALME está fundamentado numa arquitetura de sistema distribuído que separa o medidor em duas unidades: uma destinada para a medição do consumo; outra para a visualização dos dados referentes à leitura do medidor. O modelo de aplicação dessa arquitetura prevê a instalação da unidade de medição no âmbito da via pública, sendo a unidade de visualização instalada no âmbito da unidade consumidora. A instalação da unidade de medição no âmbito da via pública dificulta a implementação e utilização de circuitos não autorizados, que impeçam ou interfiram na medição dos corretos valores de consumo de energia elétrica, a serem utilizados para a cobrança desse insumo. A instalação da unidade de visualização no âmbito da unidade consumidora proporciona ao consumidor a leitura do medidor, prevista para esse tipo de aplicação. Nesse sistema, a leitura do medidor é automatizada, de forma que a aquisição dos dados de leitura dos consumos pode ser realizada no âmbito da via pública, por meio do uso de coletores de dados ou por interligação a sistemas de comunicação que utilizam redes de longa distância. Para a comunicação com os coletores de dados, é prevista a utilização da radiação infravermelha como meio de comunicação sem fio. A automatização da leitura dos medidores é fundamentada no conceito de leitura eletrônica do registrador mecânico ciclométrico, sendo exploradas abordagens que envolvem: a conversão optoeletrônica analógica; a aquisição e o processamento de imagens, e a conversão optoeletrônica digital. Os resultados obtidos nos ensaios práticos efetuados com os protótipos dos elementos do SALME foram satisfatórios, sendo validados os princípios de funcionamento desses elementos, ratificando os conceitos propostos, mostrando que os objetivos previstos neste trabalho foram alcançados em toda a sua plenitude. / BIZARRIA, J. W. P. Automated reading of electromechanical electric energy consumption meter. 2006. 255 f. Thesis (Doctoral) - Escola Politécnica, Universidade de São Paulo, São Paulo, 2006. This work embodies a conceptual design of a system focalized in automatic reading of electromechanical electric energy consumption meter, residential, with inductive transducers coupled together with cyclic mechanical registers, being that system called by Automated System for Reading of Electromechanical Meter (ASREM). On that approach are explored concepts that aim to contribute for evolution of that type of meter and others of which those concepts can be extended. The elements of that system offer contribution dedicated for the search of solutions of the current problems, mainly referring to automation of data acquisition processes of electric power consumption, and against to swindle. ASREM is based on architecture of distributed system that splits the meter into two units, being one destined to consumption measurement and other for visualization of the data related to the meter reading. The model of application of that architecture, foresees the installation of a measurement unit in the ambit of public electrical network, being the unit of visualization installed in the ambit of consumer demand. The installation of measurement unit in the ambit of public electrical network, obstructs the implementation and use of non authorized circuits that prevent or interfere in the measurement of correct values of electric power consumption to be utilized for the collection of that tariff. The installation of unit for visualization in the ambit of consumer demand, provides to the consumer the reading of the meter foreseen for that type of application. On that system the reading of the meter is automated, so that the acquisition of the reading data of the consumptions it can be accomplished in the ambit of public electrical network, by means of usage either by data collectors or by interconnection to communication systems that use long distance networks. For the communication with the data collectors that is forecasted the utilization of infrared radiation as a mean of wireless communication. The automation of meters reading is based on concept of electronic reading of the cyclic mechanical register, being explored approaches that involve: the analogical optoelectronic conversion, acquisition and image processing, and digital optoelectronic conversion. The results obtained in the practical tests performed with the prototypes of ASREM elements, were satisfactory, being validated the principles of operation of those elements, ratifying the proposed concepts, showing that the objectives foreseen in this work were fully reached.
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The Effects of Surge Flows on Residential Water Meters

Weller, Ryan P 01 May 2018 (has links)
All residential water meters have published flow rates for which they will operate as designed. These specifications include a maximum operating flow rate, which is recommended not to exceed. However, there are situations which may cause a meter to flow above the maximum flow rate. This thesis explores what effect these surge flows have on residential water meters. Twenty-one 5/8”x3/4” meters were tested in this study: three oscillating pistons, six nutating disks, nine ultrasonic, and three electromagnetic. Testing was done at the Utah Water Research Laboratory using a gravimetric test bench specifically designed for residential water meter testing. The results of this study showed that the ultrasonic meters decreased significantly in accuracy for tests above 35 gallons per minute. The nutating disk and oscillating piston meters were found to be accurate through nearly all surge flow rates tested. The electromagnetic meters were found to be accurate up to 55gallons per minute. Accuracy tests that were performed after surge flows showed that some nutating disk and oscillating piston meters decreased in accuracy at flow rates below two gallons per minute. The electronic meters had similar accuracy before and after surge flows.

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