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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.
1

The use of power electronic interface in the efficacious utilization of power in photovoltaics pumping systems

El Safi, Osman E. O. January 1990 (has links)
No description available.
2

Comparison between automated and manual DSM pumping projects / R.P. Richter

Richter, Rudolph Petrus January 2008 (has links)
The purpose of this dissertation is to identify the best alternative method of load shifting on clear water pumping systems in the mining industry. This can be done through a comparison analysis between manual and automated Demand Side Management (DSM) projects. The study holds benefits for Eskom and any client wishing to participate in the program. Eskom, by choosing the best method, will ensure sustainable load shifting while the client benefits financially through lower electricity costs. In order to perform this study, research was conducted on the requirements for additional electricity supply in South Africa. Research showed that there is an urgent requirement for additional electricity supply to ensure continued economical growth. DSM was identified as one of the most favourable methods that could be implemented to address the problem. A reason for this is DSM projects are economically viable and can be implemented in a relatively short time. The initiative would also decrease the need for increasing electrical generation capacity. During the research study important information regarding the computation process for load shifting and cost saving performance was gathered. Research was also conducted on the effect of DSM on labour and maintenance cost reduction, as well as economical engineering methods that can be used for alternative selection. The difference in performance between automated and manual systems was compared. The results showed that a 40% improvement of automated systems over manual systems were attainable and sustainable. This will realise a total saving of approximately 45% in electricity costs for the client. Savings in labour and maintenance costs are shown to be achievable through the automation of pumping systems. These saving results were used in the Engineering Economic alternative selection methods where applicable. Economic calculations confirmed that automated projects are the most viable control method. From the comparison study, it is shown that automated controlled systems are more advantageous than manually controlled systems. It will therefore be in the best interest of the client to automate a manually controlled pumping system, as it will result in additional load shifting and cost saving. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2009.
3

Comparison between automated and manual DSM pumping projects / R.P. Richter

Richter, Rudolph Petrus January 2008 (has links)
The purpose of this dissertation is to identify the best alternative method of load shifting on clear water pumping systems in the mining industry. This can be done through a comparison analysis between manual and automated Demand Side Management (DSM) projects. The study holds benefits for Eskom and any client wishing to participate in the program. Eskom, by choosing the best method, will ensure sustainable load shifting while the client benefits financially through lower electricity costs. In order to perform this study, research was conducted on the requirements for additional electricity supply in South Africa. Research showed that there is an urgent requirement for additional electricity supply to ensure continued economical growth. DSM was identified as one of the most favourable methods that could be implemented to address the problem. A reason for this is DSM projects are economically viable and can be implemented in a relatively short time. The initiative would also decrease the need for increasing electrical generation capacity. During the research study important information regarding the computation process for load shifting and cost saving performance was gathered. Research was also conducted on the effect of DSM on labour and maintenance cost reduction, as well as economical engineering methods that can be used for alternative selection. The difference in performance between automated and manual systems was compared. The results showed that a 40% improvement of automated systems over manual systems were attainable and sustainable. This will realise a total saving of approximately 45% in electricity costs for the client. Savings in labour and maintenance costs are shown to be achievable through the automation of pumping systems. These saving results were used in the Engineering Economic alternative selection methods where applicable. Economic calculations confirmed that automated projects are the most viable control method. From the comparison study, it is shown that automated controlled systems are more advantageous than manually controlled systems. It will therefore be in the best interest of the client to automate a manually controlled pumping system, as it will result in additional load shifting and cost saving. / Thesis (M.Ing. (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2009.
4

A utilização de sistemas fotovoltaicos de bombeamento para  irrigação em pequenas propriedades rurais / Use of photovoltaic pumping systems in irrigation for small rural properties

Morales, Luis Roberto Valer 15 September 2011 (has links)
Projetos piloto com sistemas fotovoltaicos de irrigação foram implementados ao redor do mundo para avaliar a confiabilidade e a viabilidade desta aplicação frente a outras opções de bombeamento. O presente trabalho dedicou atenção à compilação de informações sobre projetos com sistemas fotovoltaicos de bombeamento para uso na irrigação. A partir dessa compilação foi realizada uma síntese das experiências com identificação das principais barreiras e potencialidades de seu uso no Brasil. Levando em conta as lições aprendidas em projetos anteriores, o trabalho é finalizado com recomendações e orientações para implantação de projetos de sistemas fotovoltaicos de bombeamento para irrigação em pequenas propriedades rurais. / Pilot projects with photovoltaic irrigation systems have been implemented around the world to evaluate the reliability and feasibility of this application. This paper has devoted attention to compiling information about projects with photovoltaic pumping systems for use in irrigation. From this compilation, a synthesis of experience, the key barriers and the potential for their use in Brazil were made. Taking into account the lessons learned in previous projects the work shows recommendations and guidelines for implementation of projects for photovoltaic pumping systems for irrigation on small farms.
5

A utilização de sistemas fotovoltaicos de bombeamento para  irrigação em pequenas propriedades rurais / Use of photovoltaic pumping systems in irrigation for small rural properties

Luis Roberto Valer Morales 15 September 2011 (has links)
Projetos piloto com sistemas fotovoltaicos de irrigação foram implementados ao redor do mundo para avaliar a confiabilidade e a viabilidade desta aplicação frente a outras opções de bombeamento. O presente trabalho dedicou atenção à compilação de informações sobre projetos com sistemas fotovoltaicos de bombeamento para uso na irrigação. A partir dessa compilação foi realizada uma síntese das experiências com identificação das principais barreiras e potencialidades de seu uso no Brasil. Levando em conta as lições aprendidas em projetos anteriores, o trabalho é finalizado com recomendações e orientações para implantação de projetos de sistemas fotovoltaicos de bombeamento para irrigação em pequenas propriedades rurais. / Pilot projects with photovoltaic irrigation systems have been implemented around the world to evaluate the reliability and feasibility of this application. This paper has devoted attention to compiling information about projects with photovoltaic pumping systems for use in irrigation. From this compilation, a synthesis of experience, the key barriers and the potential for their use in Brazil were made. Taking into account the lessons learned in previous projects the work shows recommendations and guidelines for implementation of projects for photovoltaic pumping systems for irrigation on small farms.
6

Avaliação de sistemas fotovoltaicos de bombeamento / Evaluation of Photovoltaic Pumping Systems

Melendez, Teddy Arturo Flores 22 April 2009 (has links)
A presente dissertação aborda a avaliação de três sistemas fotovoltaicos de bombeamento, que compreendem duas configurações com equipamentos dedicados à tecnologia fotovoltaica e um com equipamentos alternativos com potências entre 0,75 CV e 1,0 CV. Os resultados mostram que a configuração alternativa apresenta menor eficiência diária do sistema motobomba. A avaliação econômica revela a competitividade da configuração alternativa frente aos sistemas importados dedicados à tecnologia fotovoltaica. Alia-se a isso a disponibilidade dos equipamentos de condicionamento de potência e a facilidade de reposição. Verificou-se também que a configuração alternativa, conversor de freqüência WEG CFW08 e motobomba SOMAR de 1,0 CV e 8 estágios, trabalha com eficiência diária próxima aos 30% na faixa de operação de 20 a 40 metros de coluna dágua. Portanto, com uma adequada escolha da motobomba para a configuração alternativa, podem-se obter desempenhos semelhantes aos obtidos com sistemas importados dedicados à tecnologia fotovoltaica. Para 30 metros, a configuração alternativa bombeou somente 1% a menos do que o sistema Grundfos. O custo do volume bombeado para 30m de altura manométrica total do sistema alternativo é 22% menor do que o sistema Grundfos e 51% mais econômico do que o sistema Solarjack (Sun Pumps). / The present dissertation shows the evaluation of three Photovoltaic Pumping Systems, which involves two configurations: the equipment dedicated to the photovoltaic technology and the alternative equipment with nominal powers between 0.75 CV and 1.0 CV. The results show that the alternative configuration attained minor daily efficiency of the motopump system. The economic evaluation reveals the competitiveness of the alternative configuration in comparison with imported photovoltaic technology dedicated systems. It also should be considered the availability of equipment for power conditioning and the facility of replacement. It was also verified that the alternative configuration, variable speed drive WEG CFW08 and 1.0 CV SOMAR motor pump with 8 stages, works with daily efficiency near 30% in the 20 to 40 meters operation range. Therefore, with an adequate choice of the motor pump for the alternative configuration, performances similar to the imported photovoltaic technology dedicated systems can be obtained. For 30 meters, the alternative configuration pumped only 1% less than the Grundfos system. The cost of pumped volume for 30 meters of manometer total height of the alternative system is 22% cheaper than the system Grundfos and 51% cheaper than the system Solarjack (Sun Pumps).
7

Avaliação de sistemas fotovoltaicos de bombeamento / Evaluation of Photovoltaic Pumping Systems

Teddy Arturo Flores Melendez 22 April 2009 (has links)
A presente dissertação aborda a avaliação de três sistemas fotovoltaicos de bombeamento, que compreendem duas configurações com equipamentos dedicados à tecnologia fotovoltaica e um com equipamentos alternativos com potências entre 0,75 CV e 1,0 CV. Os resultados mostram que a configuração alternativa apresenta menor eficiência diária do sistema motobomba. A avaliação econômica revela a competitividade da configuração alternativa frente aos sistemas importados dedicados à tecnologia fotovoltaica. Alia-se a isso a disponibilidade dos equipamentos de condicionamento de potência e a facilidade de reposição. Verificou-se também que a configuração alternativa, conversor de freqüência WEG CFW08 e motobomba SOMAR de 1,0 CV e 8 estágios, trabalha com eficiência diária próxima aos 30% na faixa de operação de 20 a 40 metros de coluna dágua. Portanto, com uma adequada escolha da motobomba para a configuração alternativa, podem-se obter desempenhos semelhantes aos obtidos com sistemas importados dedicados à tecnologia fotovoltaica. Para 30 metros, a configuração alternativa bombeou somente 1% a menos do que o sistema Grundfos. O custo do volume bombeado para 30m de altura manométrica total do sistema alternativo é 22% menor do que o sistema Grundfos e 51% mais econômico do que o sistema Solarjack (Sun Pumps). / The present dissertation shows the evaluation of three Photovoltaic Pumping Systems, which involves two configurations: the equipment dedicated to the photovoltaic technology and the alternative equipment with nominal powers between 0.75 CV and 1.0 CV. The results show that the alternative configuration attained minor daily efficiency of the motopump system. The economic evaluation reveals the competitiveness of the alternative configuration in comparison with imported photovoltaic technology dedicated systems. It also should be considered the availability of equipment for power conditioning and the facility of replacement. It was also verified that the alternative configuration, variable speed drive WEG CFW08 and 1.0 CV SOMAR motor pump with 8 stages, works with daily efficiency near 30% in the 20 to 40 meters operation range. Therefore, with an adequate choice of the motor pump for the alternative configuration, performances similar to the imported photovoltaic technology dedicated systems can be obtained. For 30 meters, the alternative configuration pumped only 1% less than the Grundfos system. The cost of pumped volume for 30 meters of manometer total height of the alternative system is 22% cheaper than the system Grundfos and 51% cheaper than the system Solarjack (Sun Pumps).
8

Sistema inteligente para o controle de pressão De redes de distribuição de água abastecidas Por bombas associadas em paralelo

Barros Filho, Emânuel Guerra de 05 December 2016 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2017-05-26T11:40:16Z No. of bitstreams: 1 arquivototal.pdf: 8290765 bytes, checksum: 60cc04d99eb6779eb21f6ce5385803d1 (MD5) / Made available in DSpace on 2017-05-26T11:40:17Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 8290765 bytes, checksum: 60cc04d99eb6779eb21f6ce5385803d1 (MD5) Previous issue date: 2016-12-05 / The objective of this research is to develop an intelligent system based on artificial neural networks for water distribution systems that operate with pumps associated in parallel. The system aims at process automation and the definition of operating state for electric motors (on, off or with partial rotation), aiming at the same time the pressure control and reduction of electric power consumption. The developed intelligent system is a generic one, which allows the application of control structure in similar processes, and it was applied in a fully instrumented test rig that emulates a real system of water supply. The results showed that the performance of the artificial neural network is quite satisfactory, and thus can be successfully implemented in other similar water distribution systems in order to reduce consumption of water and electric energy, decrease costs of maintenance, and increase the degree of reliability of operational procedures. / O objetivo desta pesquisa é desenvolver um sistema inteligente baseado em redes neurais artificiais para redes de distribuição de água que operam com bombas associadas em paralelo. O sistema tem por finalidade a automação do processo e a definição do estado de funcionamento dos motores elétricos (ligado, desligado ou com rotação parcial), visando simultaneamente ao controle de pressão e à redução do consumo de energia elétrica. O sistema inteligente desenvolvido é genérico, o que permite a aplicação da estrutura de controle em processos semelhantes, e foi aplicado em uma bancada experimental totalmente instrumentalizada que emula um sistema real de abastecimento de água. Os resultados mostraram que o desempenho da rede neural artificial é bastante satisfatório, e, assim, poderá ser implementada com sucesso em outros sistemas de distribuição de água similares, a fim de proporcionar redução do consumo de água e energia elétrica, diminuição dos custos de manutenção e aumento do grau de confiabilidade dos procedimentos operacionais.
9

Comportamento elétrico, mecânico e hidráulico de um sistema de bombeamento sob o enfoque da eficiência energética

Guimarães, Ronaldo 24 January 2008 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This thesis aims to present a methodology for comparing the performance electrical, mechanical and hydraulic under the focus of the energy efficiency of pumping systems controlled by valves of strangulation or by the frequency converters. The trigger is held by engines of the line standard or high efficiency. Therefore, this paper presents the simulation in domain of time from a computer platform called ATP (Alternative Transient Program). Complementing the aspects earlier, the validation of proposal modeling, is performed by comparing the simulated values and those from the tests. Finally, it should be emphasized that the laboratory experiments were performed in the laboratory for energy efficiency of the Faculty of Electrical Engineering of the Federal University of Uberlândia. / Esta dissertação tem por objetivo apresentar uma metodologia de comparação do desempenho elétrico, mecânico e hidráulico, sob o enfoque da eficiência energética, de sistemas de bombeamento controlados por válvulas de estrangulamento ou por inversores de freqüência. O acionamento é realizado pelos motores da linha padrão ou de alto rendimento. Neste sentido, este trabalho apresenta a simulação no domínio do tempo a partir de uma plataforma computacional denominada ATP (Alternative Transient Program). Complementando os aspectos anteriores, a validação da modelagem proposta, é realizada através da comparação entre os valores simulados e aqueles oriundos dos ensaios experimentais. Finalmente, deve-se destacar que os experimentos laboratoriais foram executados no laboratório de eficiência energética da Faculdade de Engenharia Elétrica da Universidade Federal de Uberlândia. / Mestre em Ciências

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