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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.
21

Optimering av spillvattenflöden

Berglund, Filip January 2022 (has links)
This thesis aims to produce a control strategy that minimizes the energy usage of the pumps in the sewer system of Växjö City. The pumps are located in a small number of pumping stations. These are connected by a network of pipes in a way that requires the control of the pumps to be coordinated, both within and between the pumping stations. A model of the system based on fluid mechanics is proposed and from this an optimization problem is constructed for the control problem. When the optimization problem is reformulated as a hierarchy of smaller problems these problems can be solved sequentially and the computational requirements are low. The resulting control strategy gives an optimal control at each flow rate to the waste water treatment plant, and the results show that an optimal control can yield significant energy savings. The control strategy is also shown to be stable with regards to errors in the model. / Detta arbete syftar till att beräkna en energieffektiv styrstrategi för pumpar i spillvattensystemet i Växjö stad. Pumparna finns i ett fåtal pumpstationer som är sammankopplade via ett rörsystem så att styrningen av pumparna behöver koordineras, både inom och mellan pumpstationerna. Utifrån en framtagen fysikalisk modell av systemet formuleras ett optimeringsproblem för att finna en energieffektiv styrning. Detta problem kan lösas på korta beräkningstider genom att det delas upp i en hierarki av mindre delproblem som löses sekventiellt. Den resulterande styrstrategin ger en optimal styrning för olika totala flöden i spillvattensystemet, och resultaten visar att en effektiv styrstrategi kan ge påtagliga besparingar i pumparnas energiförbrukning. Styrstrategin har även studerats gällande känslighet för viss osäkerhet i modellen och uppvisar stabilitet.
22

Otimização do acoplamento de geradores fotovoltaicos a motores de corrente alternada através de conversores de frequência comerciais para acionar bombas centrífugas / Optimization of Photovoltaic Pumping Systems that use Variable-speed Drive and Conventional Induction Motor with Centrifugal Pump

Brito, Alaan Ubaiara 05 May 2006 (has links)
O trabalho dedica atenção à otimização do acoplamento de geradores fotovoltaicos a motores de corrente alternada através de conversores de frequência comerciais, para acionar bombas centrífugas para fins de bombeamento de água. Procedimentos para otimização deste novo tipo de configuração são propostos. As ações de otimização são avaliadas através de ensaios experimentais realizados em uma bancada desenvolvida para este propósito. A bancada desenvolvida permite simular poços de até 100 m de profundidade. Resultados da operação de um protótipo instalado em campo são apresentados. Os resultados da pesquisa comprovam que este novo tipo de configuração é confiável e economicamente viável, podendo ser adotada como uma solução universal para sistemas de bombeamento de água que utilizam motobombas com potência igual ou superior a 1/2 CV. / This work is concerned with in the optimization of photovoltaic pumping systems that make use of a variable-speed drive and conventional induction motor with centrifugal pumps. Procedures for optimization of this new kind of configuration are proposed. The optimization actions are evaluated through experimental measurements accomplished in a test facility developed for this purpose. The developed test facility allows the simulation of wells with total head up to 100 m. Operation results of a prototype installed in the field are shown. The research results prove that this new kind of configuration is reliable and economically feasible, and could be adopted as a universal solution for water pumping systems with motors of 1/2 HP (metric) or higher.
23

Avaliação de um sistema de bombeamento de água alimentado por painéis fotovoltaicos / Evaluation of a water pumping system fed by photovoltaic panels

Michels, Roger Nabeyama 06 June 2007 (has links)
Made available in DSpace on 2017-05-12T14:46:59Z (GMT). No. of bitstreams: 1 Roger Nabeyama Michels.pdf: 4361240 bytes, checksum: 896b2cd719d7885b070fecc71373f7e7 (MD5) Previous issue date: 2007-06-06 / The current dissertation describes an experiment to evaluate a water pumping system activated by two photovoltaic panels installed at The Federal Technological University of Paraná FTUPR, Medianeira Campus, in the State of Paraná, Brazil. The city of Medianeira s latitude and longitude are 25º17 43 south and 54º03 38 west respectively, with an altitude of 500.7 meters (1,642.72 feet). The system operated in a real working situation, pumping water to a 20 meters (65.62 feet) elevation. Data were collected, from February 2005 to November 2005, by means of a computerized data collector made by Campbell Scientific Inc that made possible collecting and applying irradiance values in the panel plane, generated current and tension, panel temperature, pressure and consume. Data readings were made at a 1-hertz frequency and stored every minute. Through calculi, the system efficiency and energy values and hydraulic strength were obtained. Winter solstice showed 9.58% efficiency with daily pumping of 2,056.44 liters (543.14 gallons) whereas summer solstice confirmed 9.07% efficiency with daily pumping of 2,377.21 liters (627.86 gallons). Winter day s highest efficiency is associated to the lowest temperature in those days compared to summer days, and the factor that prompted larger pumped water consume, during summer days, was related to solar insulation time that is longer if compared to winter days. Total water pumped during the experiment period was 435,042.20 liters (114,900.99 Gallons). / A presente dissertação descreve o experimento desenvolvido com a finalidade de avaliar um sistema de bombeamento de água acionado por dois painéis fotovoltaicos instalado nas dependências da Universidade Tecnológica Federal do Paraná UTFPR, Campus Medianeira, estado do Paraná, Brasil. O município está localizado no oeste paranaense com 25º17 43 Latitude sul, 54º03 38 Longitude oeste e com altitude de 500,7 metros. O sistema trabalhou em situação real de funcionamento, bombeando água a uma altura de 20 metros. Foram coletados dados de fevereiro de 2005 a novembro de 2005; utilizou-se um coletor de dados computadorizado da marca Campbell Scientific INC., o que possibilitou adquirir e armazenar os valores de irradiância no plano do painel, tensão e corrente gerada, temperatura no painel, pressão e vazão. A leitura dos dados foi realizada com freqüência de 1 hertz e armazenada a cada 1 minuto. Através de cálculos obtiveram-se os valores de potência e eficiência do sistema e a potência hidráulica. O solstício de inverno apresentou eficiência de 9,58% com bombeamento diário de 2.056,44 litros, enquanto que o solstício de verão apresentou eficiência de 9,07% com bombeamento diário de 2.377,21 litros. A maior eficiência nos dias de inverno está atrelada às menores temperaturas nestes dias se comparado aos dias de verão e o fator que provocou uma maior vazão de água bombeada nos dias de verão está ligado ao tempo de insolação solar que é maior se comparado aos dias de inverno. O total de água bombeada durante o período do experimento foi de 435.042,20 litros.
24

Otimização do acoplamento de geradores fotovoltaicos a motores de corrente alternada através de conversores de frequência comerciais para acionar bombas centrífugas / Optimization of Photovoltaic Pumping Systems that use Variable-speed Drive and Conventional Induction Motor with Centrifugal Pump

Alaan Ubaiara Brito 05 May 2006 (has links)
O trabalho dedica atenção à otimização do acoplamento de geradores fotovoltaicos a motores de corrente alternada através de conversores de frequência comerciais, para acionar bombas centrífugas para fins de bombeamento de água. Procedimentos para otimização deste novo tipo de configuração são propostos. As ações de otimização são avaliadas através de ensaios experimentais realizados em uma bancada desenvolvida para este propósito. A bancada desenvolvida permite simular poços de até 100 m de profundidade. Resultados da operação de um protótipo instalado em campo são apresentados. Os resultados da pesquisa comprovam que este novo tipo de configuração é confiável e economicamente viável, podendo ser adotada como uma solução universal para sistemas de bombeamento de água que utilizam motobombas com potência igual ou superior a 1/2 CV. / This work is concerned with in the optimization of photovoltaic pumping systems that make use of a variable-speed drive and conventional induction motor with centrifugal pumps. Procedures for optimization of this new kind of configuration are proposed. The optimization actions are evaluated through experimental measurements accomplished in a test facility developed for this purpose. The developed test facility allows the simulation of wells with total head up to 100 m. Operation results of a prototype installed in the field are shown. The research results prove that this new kind of configuration is reliable and economically feasible, and could be adopted as a universal solution for water pumping systems with motors of 1/2 HP (metric) or higher.
25

Avaliação de um sistema de bombeamento de água alimentado por painéis fotovoltaicos / Evaluation of a water pumping system fed by photovoltaic panels

Michels, Roger Nabeyama 06 June 2007 (has links)
Made available in DSpace on 2017-07-10T19:23:45Z (GMT). No. of bitstreams: 1 Roger Nabeyama Michels.pdf: 4361240 bytes, checksum: 896b2cd719d7885b070fecc71373f7e7 (MD5) Previous issue date: 2007-06-06 / The current dissertation describes an experiment to evaluate a water pumping system activated by two photovoltaic panels installed at The Federal Technological University of Paraná FTUPR, Medianeira Campus, in the State of Paraná, Brazil. The city of Medianeira s latitude and longitude are 25º17 43 south and 54º03 38 west respectively, with an altitude of 500.7 meters (1,642.72 feet). The system operated in a real working situation, pumping water to a 20 meters (65.62 feet) elevation. Data were collected, from February 2005 to November 2005, by means of a computerized data collector made by Campbell Scientific Inc that made possible collecting and applying irradiance values in the panel plane, generated current and tension, panel temperature, pressure and consume. Data readings were made at a 1-hertz frequency and stored every minute. Through calculi, the system efficiency and energy values and hydraulic strength were obtained. Winter solstice showed 9.58% efficiency with daily pumping of 2,056.44 liters (543.14 gallons) whereas summer solstice confirmed 9.07% efficiency with daily pumping of 2,377.21 liters (627.86 gallons). Winter day s highest efficiency is associated to the lowest temperature in those days compared to summer days, and the factor that prompted larger pumped water consume, during summer days, was related to solar insulation time that is longer if compared to winter days. Total water pumped during the experiment period was 435,042.20 liters (114,900.99 Gallons). / A presente dissertação descreve o experimento desenvolvido com a finalidade de avaliar um sistema de bombeamento de água acionado por dois painéis fotovoltaicos instalado nas dependências da Universidade Tecnológica Federal do Paraná UTFPR, Campus Medianeira, estado do Paraná, Brasil. O município está localizado no oeste paranaense com 25º17 43 Latitude sul, 54º03 38 Longitude oeste e com altitude de 500,7 metros. O sistema trabalhou em situação real de funcionamento, bombeando água a uma altura de 20 metros. Foram coletados dados de fevereiro de 2005 a novembro de 2005; utilizou-se um coletor de dados computadorizado da marca Campbell Scientific INC., o que possibilitou adquirir e armazenar os valores de irradiância no plano do painel, tensão e corrente gerada, temperatura no painel, pressão e vazão. A leitura dos dados foi realizada com freqüência de 1 hertz e armazenada a cada 1 minuto. Através de cálculos obtiveram-se os valores de potência e eficiência do sistema e a potência hidráulica. O solstício de inverno apresentou eficiência de 9,58% com bombeamento diário de 2.056,44 litros, enquanto que o solstício de verão apresentou eficiência de 9,07% com bombeamento diário de 2.377,21 litros. A maior eficiência nos dias de inverno está atrelada às menores temperaturas nestes dias se comparado aos dias de verão e o fator que provocou uma maior vazão de água bombeada nos dias de verão está ligado ao tempo de insolação solar que é maior se comparado aos dias de inverno. O total de água bombeada durante o período do experimento foi de 435.042,20 litros.
26

An Internship on Developing a Solar Water Pumping System at Microsol International™

Sivakumar, Karthik 28 April 2011 (has links)
No description available.
27

Design And Construction Of An Educational Pump Bench With Operational Controls

Guner, Berkay 01 December 2005 (has links) (PDF)
System characteristics of automated pumping systems may change due to wear, aging of piping, and accumulation of deposits in the system and/or due to configuration changes. Such changes might result in conflicts between the controlling algorithms and the actual system requirements for each particular case. The said mismatch between the actual physical system and the software controlling it, may result in inefficient operation of the pump which may even lead to total system failures (overpressurization of instrumentation and sensing elements etc.) due to temporary malfunctioning of the system components or permanent damages incurred by them during operating under unsuitable conditions. It is intended in this study to design and construct an experimental automated pump bench with operational components (mechanical, electronical and instrumentation etc.), serving in a system introducing multiple geometric heads and its controlling and monitoring software in order to visualize effects of the above-mentioned cases for education and training purposes. System characteristics data acquisition module (system test module) provides the means of recognizing new pump and system characteristics, provided that they were changed due to some reason (throttled valve, changed pump speed, changed flowrate or elevation of discharge etc.). Then the pump operation module enables users to make comparative judgments by observing the effects of the abovementioned changes. Above-mentioned testing sequence and monitoring of changing physical quantities were achieved by employing four pressure transducers, a custom made DC motor operated -throttling valve with position feedback which was designed and constructed specifically for this study and a variable frequency drive (VFD) which were all connected to a custom made Main Control Circuit (MCC) Board.
28

Sistema especialista fuzzy para dimensionamento de bombeio mec?nico

Freitas, Cassio Higino de 22 February 2010 (has links)
Made available in DSpace on 2014-12-17T15:47:52Z (GMT). No. of bitstreams: 1 CassioHF_DISSERT.pdf: 1503543 bytes, checksum: f8c5d434affbf0ef65dde0a97d3eb071 (MD5) Previous issue date: 2010-02-22 / Despite the emergence of other forms of artificial lift, sucker rod pumping systems remains hegemonic because of its flexibility of operation and lower investment cost compared to other lifting techniques developed. A successful rod pumping sizing necessarily passes through the supply of estimated flow and the controlled wear of pumping equipment used in the mounted configuration. However, the mediation of these elements is particularly challenging, especially for most designers dealing with this work, which still lack the experience needed to get good projects pumping in time. Even with the existence of various computer applications on the market in order to facilitate this task, they must face a grueling process of trial and error until you get the most appropriate combination of equipment for installation in the well. This thesis proposes the creation of an expert system in the design of sucker rod pumping systems. Its mission is to guide a petroleum engineer in the task of selecting a range of equipment appropriate to the context provided by the characteristics of the oil that will be raised to the surface. Features such as the level of gas separation, presence of corrosive elements, possibility of production of sand and waxing are taken into account in selecting the pumping unit, sucker-rod strings and subsurface pump and their operation mode. It is able to approximate the inferente process in the way of human reasoning, which leads to results closer to those obtained by a specialist. For this, their production rules were based on the theory of fuzzy sets, able to model vague concepts typically present in human reasoning. The calculations of operating parameters of the pumping system are made by the API RP 11L method. Based on information input, the system is able to return to the user a set of pumping configurations that meet a given design flow, but without subjecting the selected equipment to an effort beyond that which can bear / Apesar do surgimento de outras t?cnicas de eleva??o artificial de petr?leo, sistemas de bombeio mec?nico mant?m-se hegem?nicos devido ? sua flexibilidade de atua??o e custo menor de investimento se comparada com outras t?cnicas de eleva??o desenvolvidas. Um dimensionamento de bombeio mec?nico bem sucedido necessariamente passa pelo atendimento da vaz?o prevista e pelo desgaste controlado dos equipamentos de bombeio utilizados na configura??o montada. Entretanto, a concilia??o destes elementos mostrase particularmente desafiadora, sobretudo para a maioria dos projetistas que lidam com este trabalho, que n?o possuem ainda a experi?ncia necess?ria para chegar a bons projetos de bombeio em tempo h?bil. Mesmo com a exist?ncia de diversos aplicativos computacionais no mercado com o objetivo de facilitar esta tarefa, eles precisam enfrentar um exaustivo processo de tentativa e erro at? chegar a combina??o mais adequada de equipamentos para instala??o no po?o. A proposta do presente trabalho consiste em desenvolver um sistema especialista no dimensionamento de sistemas de bombeio mec?nico. Ele tem a miss?o de guiar um engenheiro de petr?leo na tarefa de selecionar um conjunto de equipamentos apropriados ao contexto provido pelas caracter?sticas do ?leo que ser? produzido. Caracter?sticas como o n?vel de separa??o do g?s, presen?a de elementos corrosivos, possibilidade de produ??o de areia e de parafina??o s?o levados em considera??o na escolha da bomba de fundo, coluna de hastes e unidade de bombeio, bem como as caracter?sticas de opera??o dos mesmos. Ele ? capaz de aproximar seu processo de infer?ncia da forma do racioc?nio humano, o que gera resultados mais pr?ximos daqueles obtidos por um especialista. Para tanto, suas regras de produ??o foram elaboradas com base na teoria dos conjuntos fuzzy, capazes de modelar conceitos imprecisos tipicamente presentes no racioc?nio humano. Os c?lculos dos par?metros operacionais do sistema de bombeio s?o feitos por meio do m?todo API RP 11L. Com base em informa??es de entrada, o sistema ? capaz de retornar ao usu?rio um conjunto de configura??es de bombeio mec?nico que atendam uma determinada vaz?o de projeto, por?m sem submeter os equipamentos selecionados a um esfor?o al?m daquele que possam suportar
29

Optimal design of photovoltaic water pumping systems for rural communities – a technical, economic and social approach / Conception optimale des systèmes photovoltaïques de pompage d’eau pour les communautés rurales - une approche technique, économique et sociale

Meunier, Simon 06 December 2019 (has links)
Les systèmes photovoltaïques de pompage d'eau (PVWPS) sont une solution intéressante pour améliorer l’accès à l’eau dans les communautés rurales des pays en voie de développement. Cette thèse développe une méthodologie de conception optimale des PVWPS pour l’accès à l’eau domestique basée sur une approche interdisciplinaire. L’objectif est de déterminer les dimensionnements du PVWPS et ses positions géographiques dans le village qui maximisent l’impact positif du système sur le développement socio-économique et minimisent son coût sur cycle de vie. Cette méthodologie est appliquée au cas d’un village rural du Burkina Faso, où nous avons collecté des données techniques et sociaux-économiques depuis 2 ans. La première originalité principale de ce travail est la modélisation du lien entre la conception du PVWPS et son impact socio-économique, ce qui permet d’inclure l’impact socio-économique comme fonction objectif de l’optimisation. La seconde originalité principale est l’intégration de la position géographique du PVWPS dans le village comme variable d’optimisation, en plus du dimensionnement du système. Cette méthodologie pourrait également être appliquée à la mise en place d'autres types de systèmes, tels que les moulins communaux alimentés par énergie photovoltaïque dans les zones isolées ou les bornes de recharges publiques pour les véhicules électriques dans les villes. / Photovoltaic water pumping systems (PVWPS) are an interesting solution to improve access to water in rural communities of developing countries. This thesis develops a methodology for the optimal design of PVWPS for domestic consumption based on an interdisciplinary approach. The objective is to determine the sizings of the PVWPS and its geographical positions in the village that maximize the positive impact of the system on socio-economic development and minimize its life-cycle cost. This methodology is applied to the case of a rural village in Burkina Faso, where we have been collecting technical and socio-economic data for 2 years. The first main originality of this work is the modelling of the link between the design of a PVWPS and its socio-economic impact, which allows to include the socio-economic impact to be included as an objective function of the optimisation. The second main originality is the inclusion of the geographical position of the PVWPS in the village as an optimisation variable, in addition to the sizing of the system. There is potential for applying the proposed methodology for the set-up of other types of systems such as community mills powered by photovoltaic energy in isolated areas and public charging points for electrical vehicles in cities.

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