The thesis numerically explores the use and behavior of Active Hydraulic Devices (AHDs), creating a new capability to simulate and control a pipe system’s transient performance. Automatic control valves are the first type of AHDs studied in this research. Due to the challenges inherent in the design of a pressure relief valve (PRV), the general principles of PRV use and selection are studied along with the system’s response to the PRV parameters. A new application of PID (proportional, integral and derivative) control valve is envisioned that combines a remote sensor at the upstream end of a pipeline to create a non- or semi- reflective boundary at the downstream end. Case studies show that, with such a boundary, the reflection and resonance of pressure waves within the pipeline are sometimes eliminated and invariably limited. The second type of AHDs studied in this research is the governed hydro turbine, the most complicated hydraulic component in terms of transient analysis and waterhammer control. A complete numerical model is developed for the turbine installations in either urban water networks or conventional hydropower generation systems. Using the model, transient simulations for several realistic hydro projects are presented along with various transient control measures.

The thesis numerically explores the use and behavior of Active Hydraulic Devices (AHDs), creating a new capability to simulate and control a pipe system’s transient performance. Automatic control valves are the first type of AHDs studied in this research. Due to the challenges inherent in the design of a pressure relief valve (PRV), the general principles of PRV use and selection are studied along with the system’s response to the PRV parameters. A new application of PID (proportional, integral and derivative) control valve is envisioned that combines a remote sensor at the upstream end of a pipeline to create a non- or semi- reflective boundary at the downstream end. Case studies show that, with such a boundary, the reflection and resonance of pressure waves within the pipeline are sometimes eliminated and invariably limited. The second type of AHDs studied in this research is the governed hydro turbine, the most complicated hydraulic component in terms of transient analysis and waterhammer control. A complete numerical model is developed for the turbine installations in either urban water networks or conventional hydropower generation systems. Using the model, transient simulations for several realistic hydro projects are presented along with various transient control measures.

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yes / This paper models a hydro turbine based on the dynamic description of the hydraulic system having a surge tank and elastic water hammer. The dynamic of the hydraulic system is transformed from transfer function form into the differential equation model in relative value. This model is then combined with the motion equation of the main servomotor to form the nonlinear model of the hydro turbine, in which the power of the hydro turbine is calculated using algebraic equation. A new control model is thus proposed in which the dynamic of the surge tank is taken as an additional input of control items. As such, the complex hydraulic system is decomposed into a classical one penstock and one machine model with an additional input control. Therefore, the order of the system is descended. As a result, the feasibility of the system is largely improved. The simulated results show that the additional input of the surge tank is effective and the proposed method is realizable. / National Natural Science Foundation of China (50839003, 50949037, 51179079), Natural Science Foundation of Yunnan Province (No. 2008GA027)

La récupération d'énergie est un procédé très fréquent qui peut être observé sous de nombreuses formes dans la nature. Des espèces de poissons ou d'oiseaux sont par exemple connues pour exploiter leurs environnements afin d'accomplir une propulsion à moindre effort. L'objectif de ces travaux est de concevoir un concept d'hydro-éolienne oscillante basé sur des dynamiques similaires. La notion d'interaction fluide-structure est présentée pour expliquer le moyen d'alimentation utilisé dans le transfert énergétique de ce concept. Un mécanisme d'aile oscillante est spécialement modélisé théoriquement et numériquement pour analyser la dynamique de l'hydro-éolienne. L'asymétrie des oscillations, propre aux couplages multi-physiques, est particulièrement considérée pour maximiser le rendement du récupérateur d'énergie oscillant. On remarque que l'intégration de cette caractéristique des oscillations est présente dans la théorie de Couchet qui complète le modèle instationnaire de Theodorsen pour estimer les efforts aérodynamiques d'un profil d'aile oscillant non-symétriquement par rapport au sens de l'écoulement. L'analyse énergétique de l'oscillateur révèle de tellement bons rendements que la proximité avec la limite de Betz provoque un doute sur la définition de l'efficacité pour quantifier le transfert énergétique. En effet, l'optimisation d'un récupérateur d'énergie hydro-aéro-élastique est réalisée soit en maximisant la puissance dissipée par l'oscillateur soit au diminuant artificiellement la puissance disponible dans le fluide en adaptant la section de balayage de l'aile. Une autre définition de l'efficacité énergétique est développée sur la base de la théorie de Couchet pour lever cette incertitude. L'analyse de cet indicateur met en valeur l'importance du rôle du sillage du déplacement asymétrique de l'aile dans la récupération d'énergie. / Energy harvesting is a common process presents in so many ways in nature. Fishes and birds use for example their surroundings in order to produce propulsion without any effort. The focus of this thesis is to design a hydro-aéro-elastic harvester based on these dynamics. The fluid-structure interaction is introduced to explain the energy supply of the concept. An oscillating-wing-mechanism is theoretically and numerically developed in the aim to investigate the behavior of the marine-wind turbine. The energetic efficiency is then maximized by the asymmetric oscillations relative to the fluid-structure coupling. Note that the non-symmetric characteristic of the oscillation is included in the theory of Couchet which completes the unsteady aerodynamic theory of Theodorsen. Unusual high performances of the oscillating harvester suggest some apprehensions reading the efficiency’s definition. Indeed, the hydro-aéro-elastic harvester optimization can be achieved ether by increasing the power output or by decreasing the power available in the fluid artificially modified by the sweep section of the foil. These uncertainties are resolved by considering another definition of the energetic efficiency which is developed according to the theory of Couchet. The performance analysis of the new factor presents the contribution of the wake induced by the asymmetric oscillation of the foil on the energy harvesting quantities.

In this thesis, a parametric methodology is investigated to design a Pump-Turbine system using Computational Fluid Dynamics ( CFD ). The parts of Pump-Turbine are created parametrically according to the experience curves and theoretical design methods. Then, these parts are modified to obtain 500 kW turbine working as a pump with 28.15 meters head. The final design of Pump-Turbine parts are obtained by adjusting parameters according to the results of the CFD simulations. The designed parts of the Pump-Turbine are spiral case, stay vanes, guide vanes, runner and draft tube. These parts are designed to obtain not only turbine mode properties but also pump mode properties.

yes / Traditional rotor dynamics mainly focuses on the steady- state behavior of the rotor and shafting. However, for systems such as hydro turbine generating sets (HTGS) where the control and regulation is frequently applied, the shafting safety and stabilization in transient state is then a key factor. The shafting transient state inevitably involves multiparameter domain, multifield coupling, and coupling dynamics. In this paper, the relative value form of the Lagrange function and its equations have been established by defining the base value system of the shafting. Takingthe rotation angle and the angular speed of the shafting as a link, the shafting lateral vibration and generator equations are integrated into the framework of generalized Hamiltonian system. The generalized Hamiltonian control model is thus established. To make the model more general, additional forces of the shafting are taken as the input excitation in proposed model. The control system of the HTGS can be easily connected with the shafting model to form the whole simulation system of the HTGS. It is expected that this study will build a foundation for the coupling dynamics theory using the generalized Hamiltonian theory to investigate coupling dynamic mechanism among the shafting vibration, transient of hydro turbine generating sets, and additional forces of the shafting. / National Natural Science Foundation of China under Grant Nos. 51179079 and 50839003

The power output characteristics of the hydro turbine is one of the core contents for transient calculation of the hydro turbine generating sets (HTGS). In particular, the hydro turbine operates far beyond the given parameters region during the load rejection transient. As such, obtaining the complete characteristics of the hydro turbine becomes one of the key issues in calculating the transient process. In this study, methods for calculating the energy losses are proposed by analyzing the general characteristics of the inner energy losses within the hydro turbine. Characteristic parameters in the hydro turbine power model are calculated from the synthetical characteristics of the model hydro turbine. The transient power model of the hydro turbine has been established and applied to calculate and reconstruct the complete characteristics of the hydro turbine. Furthermore, the relationship curve between the mechanical friction loss power and the rotation speed under different head can be established by combing the runaway curve with the proposed turbine power model. This relationship is applied to construct the complete characteristics of the mechanical friction loss. Combining the proposed two complete characteristics, the power model of the hydro turbine is suitable for simulation with a wide range of fluctuations as well as the load rejection transient. Details of the computational procedures are presented and demonstrated using a case study. / The research reported here is financially supported by the National Natural Science Foundation of China under Grant No. 51579124, 51469011,51279071.

The thesis utilizes the analogy in dynamic equations between a mechanical and an electrical system to convert the steam-turbine, micro-turbine, wind-turbine and hydro-turbine generator mechanical model to equivalent electrical circuit models respectively. And based on the round rotor type and permanent magnetic rotor type synchronous generators¡¦ dynamic equations, as well as their electromagnetic torque equations, the equivalent electrical interface circuits were derived respectively. By using the interface circuit, the circuit model of synchronous generator and the equivalent electrical circuit model of turbine-generator mechanism can thus be combined into the electromechanical integrated circuit model (Thevenin¡¦s analogy circuit model and Norton's analogy circuit model). The electromechanical integrated circuit model is helpful for analyzing the energy conversion, power transmission and interactions between the mechanical and electrical systems for a turbine generator unit. In order to learn about these electromechanical interactions by using the proposed electromechanical integrated circuit model, the thesis has made a study on the torsional vibrations for a small gas turbine generator unit and for a large steam turbine generator unit respectively. By way of the frequency scanning and eigenvalue calculation, it is found that the torsional mode frequencies can be changed due to the electromechanical integration. Moreover, the small unit was more affected by the electromechanical integration than the large unit. Finally, we studied the effect of operations of an Electric Arc Furnaces (EAF) on torsional vibrations of a low capacity turbine generator. The electric system studied belongs to a practical steel plant in an industrial park. Based on the electromechanical integrated equivalent circuit model, a flywheel coupling shaft was designed. It is found by simulations that the coupling shaft can be quite effective in alleviating vibrations caused by the system unbalance arising from the EAF operations.

Orientador: Celso Pascoli Bottura / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-07T10:43:12Z (GMT). No. of bitstreams: 1 Sansevero_Glaucio_M.pdf: 643820 bytes, checksum: 45c53dc9fa719ea530adb309c5ac4ee8 (MD5) Previous issue date: 2006 / Resumo: Apesar de ter surgido na indústria há mais de 20 anos, o Controle Preditivo Baseado em Modelo (MPC) não encontrou muitas aplicações no campo de controle de máquinas rotativas. A maioria das aplicações hoje são processos químicos e petroquímicos. Contudo, alguns resultados obtidos por outros autores em controle de turbinas a gás e turbinas a vapor sugerem que sua utilização pode ser interessante no controle deste tipo de máquina e, em particular, no controle de turbinas hidráulicas. Este trabalho tem por objetivo explorar a possibilidade e discutir as vantagens e desvantagens da aplicação deste método no controle de turbinas hidráulicas tipo Francis. Iniciamos o trabalho apresentando urna descrição do MPC e explicitando o algoritmo utilizado pelo controlador. Em seguida, um modelo no espaço de estado do sistema a ser controlado é desenvolvido. Finalmente, o método é aplicado no controle da máquina em questão e os resultados obtidos através de simulações são analisados / Abstract: Despite being used in the industry for more than 20 years, Model Predictive Control (MPC) has not found many applications in the field of rotating machinery controI. The majority of the applications today are chemical and petrochemical processes. However, some results obtained by other authors for the control of gas and steam turbines, suggest that its use can be interesting for the control of this type of machine, and in particular, for the control of hydraulic turbine generators. The objective of this work is to explore the possibility and to discuss the advantages and disadvantages of the application of this method on the control of a Francis hydro turbine generator. We start the discussion presenting a description of the MPC and detailing the algorithm used by the controller. After that, a state space model of the system to be controlled is developed. Finally the method is applied for the control of the hydro turbine and the results obtained trough simulation are discussed. / Mestrado / Automação / Mestre em Engenharia Elétrica