Made available in DSpace on 2016-01-13T13:27:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-05-02. Added 1 bitstream(s) on 2016-01-13T13:32:37Z : No. of bitstreams: 1 000846492.pdf: 1180008 bytes, checksum: 21c77013514aecb32396e94d673612c1 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O problema multiobjetivo de despacho econômico e ambiental é formulado envolvendo a minimização de dois objetivos conflitantes: custo da geração termoelétrica de energia e a quantidade de emissão de poluentes, sujeitos ao atendimento da demanda e aos limites de operação dos sistema. A função objetivo relativa ao custo pode ser modelada de diferentes formas, entre elas, aquela que inclui os efeitos dos pontos de carregamento de válvula, que quando incorporados à função, transformam-na em não-diferenciável nesses pontos, além de não convexa, impossibilitando que métodos clássicos de otimização sejam empregados à resolução do problema. Devido a esse fato, grande parte dos trabalhos encontrados na literatura para resolução deste tipo de problema, não incluem esses efeitos ou, quando incluem utilizam-se de métodos heurísticos. No presente trabalho, um método híbrido envolvendo o primal-dual previsor-corretor barreira logarítima modificada, com estratégias de correção de inércia e de suavização de funções, acopladas nos métodos de solução de problemas multiobjetivo, é desenvolvido e aplicado à resolução do problema em destaque. A estratégia de correção de inércia possibilita a convergência do método para mínimos locais e a técnica de suavização tonra a função despacho econômico diferenciável nos pontos de carregamento de válvula, presentes nos termos modulares da função, possibilitando o uso do método híbrido proposto. Um novo método de resolução de problemas multi-objetivo é proposto e utilizado, variante do método Σ-restrito canalizado. Os métodos foram implementados em linguagem Matlab 2011a e aplicados em três casos-teste, demonstrando eficiência nos resultados obtidos quando comparados a outros encontrados na literatura / The multiobjective economic and environmental dispatch problem is formulated involving the minimization of two conflicting goals: the cost of power thermoelectric generation and the amount of pollutant emissions, subject to meeting demand and system operating limits. The objective function related to the cost can be modeled in different ways, among them, one that includes the effects of valve loading points, which when incorporated to the function, turn it into non-differentiable at these points, as well as non-convex, precluding that classical optimization methods are employed to solve the problem. Due to this fact, most studies found in the literature for solving this type of problem, do not include these effects or, when they are included, the heuristic methods are used. In this study, a hybrid method involving the predictor -corretor-primal-dual modified logarithmic barrier method inertia correction strategies and smothing functions, coupled to the solution methods for multiobjective problems, is developed and applied to solve the highlighted problem. The inertia correction strategy ensures that the proposed method converges to local mínima and the smoothing technique makes the economic dispatch function differentiable in valve loading points, present in modular terms of function, enabling the use of the proposed hybrid method. Variant of the Σ-constraint method, a new multiobjective optimization method is proposed and used, and called the bounded Σ-constraint method. The proposed methods were implemented in Matlab 2011a language and applied in three test cases, and the results obtained show its efficiency when compared to others found in the literature

ENGLISH ABSTRACT: This document details the design process of a 97 kW microhydro system for Roman Bay Sea Farm in Gansbaai in the Western Cape Province of South Africa. It contains a literature study of microhydro power, with a focus on the use of Pump-as-Turbine technology and direct-drive systems. The literature study leads to several possible concepts for the project, which are then evaluated and the most suitable design is found to be a reverse running pump that powers a different pump through a direct drive system. Experimental data from KSB is used to test the accuracy of various correlations that can be used to generate turbine-mode operation curves from pump curves. The final design parameters for the complete system are then determined, and presented along with a cost benefit analysis. / AFRIKAANSE OPSOMMING: Hierdie verslag dokumenteer die ontwerpsproses van ‘n 97 kW mikro hidro stelsel vir Roman Bay Sea Farm in Gansbaai in die Wes-Kaap van Suid Afrika. Dit bevat ‘n literatuurstudie van mikro hidrokrag, met ‘n fokus op Pomp-as-Turbine en direk-gekoppelde stelsels. Die literatuurstudie lei tot ‘n aantal moontlike konsepte vir die projek wat dan evalueer word sodat die mees gepaste ontwerp gekies kan word. Dit word gevind dat ‘n pomp wat verkeerd om hardloop en ‘n ander pomp direk van krag voorsien die mees gepaste ontwerp is. Eksperimentele data van KSB word gebruik om die akkuraatheid van verskeie korrelasies te toets wat gebruik kan word om turbine-mode gedrag van pomp kurwes te bepaal. Die finale parameters van die hele stelsel word dan bepaal en word dan saam met ‘n koste-analise aangebied. / Centre for Renewable and Sustainable Energy Studies

The necessity to develop an automated process for the design of micro-hydro power systems was based on the increasing demand for hydropower as a renewable energy source and to develop cost effective power supplies to rural areas. The application of the formula for the design of these systems is then to simplify the selection of the turbine sizing and is made possible by the similarity laws that exist within turbine and pump families. in addition the sizing of the supply and exhaust piping is also a matter of scaling. No selection process of turbine type is included due to the limitations of cost effectiveness and the category of size into which the turbine was specified. Furthermore. a new approach to turbine design was separately undertaken to satisfy low head and low flow-rate conditions. However, it was only designed up to a cost analysis with no manufacturing having been undertaken. The axial flow turbine. which was most suited for micro-hydro was designed and built as a prototype with a standardized mounting frame. The initial conditions used to generare the velocity vectors and angles were specific to the installation site and used to computationally generate the rotor and stator blades. This required an analysis of the different profiles available as well as research into their design. Once the blade profile stacking had been determined, this was translated into a software program that developed the blades from site-specific initial conditions. However, the design of the blades was interdependent on the dimensioning of the rest of the turbine components and designing these in parallel proved to be an intricate task. With the design complete, the turbine was then installed and testing proceeded with the use of pressure gauges and the results of torque and rpm obtained from a dynamometer. Analysis of the results was undertaken and presented in graphical format with comments on both the design and results. / Thesis (M.Sc.Eng.) -University of Natal, Durban, 2000.

Thesis (doctoral)--Swedish University of Agricultural Sciences, 2007. / Includes an appendix of three papers and manuscripts, one co-authored with Per-Olov Johansson and Bengt Kriström. A second appendix reprints questionnaire used to elicit data for the three papers. Also issued electronically via World Wide Web in PDF format; online version lacks appendix.

Thesis (M.A.) -- University of Montana, 2008. / Title from author supplied metadata. Description based on contents viewed on July 15, 2009. Includes bibliographical references.

Thesis (Ph. D.)--Catholic University of America, 1932. / "Biographical note." Errata slip mounted on p. [7]. Bibliography at end of each chapter.

Thesis (M.A.)--Ohio University, June, 2009. / Title from PDF t.p. Includes bibliographical references.

Thesis (doctoral)--Københavns universitet, København, 1942. / Includes bibliographical references (p. 400-409) and index.

This master‘s thesis deals with small water power plant Beneš. The first part of the thesis tries to find causes of low efficiency of this power plant. The second part contains suggestions of construction changes for increasing of efficiency – design of new runner blades and basic parameters of new distributor.

This master thesis concerns on the utilization of new water structure for production of electric energy. The next part follows with description of the term small water power plant, the classification of small water power plants and description of their main components. The next steps decrypts the process of finding optimal location for development of small water power plant in the Eastern Bohemian region, including hydrological data, cadastral maps and the list of land owners in the potential location of my designed water power plant. Further on there is mentioned calculation and proposition their mechanical parts ( turbine and generator ) and appreciation investment effectiveness designed locations.