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Depuis une quinzaine d'années, l'éolien s'est grandement développé en nombre d'infrastructures et en puissance unitaire mais il reste toujours confronté à un problème de disponibilité de par les nombreuses pannes d'ordre mécanique ou électrique. Le but de ces travaux consiste à concevoir, modéliser et piloter des aérogénérateurs tolérants aux défauts mécaniques et électriques. Pour cela, une structure basée sur une génératrice asynchrone hexaphasée à grand nombre de paires de pôles a été retenue. L'augmentation du nombre de pôles permet de s'affranchir ou de simplifier le multiplicateur, source des pannes mécaniques, tandis que l'utilisation d'une structure multiphasée permet de poursuivre la production d'énergie lors de la perte de phases au stator ou de bras du convertisseur. Une modélisation fine de la génératrice sur la méthode des circuits internes équivalents a été réalisée et un algorithme de calcul des paramètres à partir des données géométriques de la machine a été développé permettant d'automatiser le calcul pour n'importe quels stators et schémas de bobinage. Associé au convertisseur, ce modèle a été simulé avec succès et une commande vectorielle a également été introduite à ce schéma. Cette stratégie de contrôle permet d'adapter les matrices de transformation ainsi que les paramètres des régulateurs PI en fonction du défaut et confère une tolérance aux défauts électriques. Cette adaptation permet de réduire significativement les oscillations de puissance lors de la perte d'une ou plusieurs phases. Pour valider les théories développées et déjà simulées, des essais ont été réalisés avec succès sur un banc d'essai de 24kW, image d'une éolienne connectée au réseau / For around 15 years, wind turbines have found a wide popularity and increase in terms of number and power per unit but they have still to deal with mechanical and electrical faults. Then, the aim of this thesis is to design, model and control a wind turbine generator that is able to cope with these problems. For this, a structure based on a squirrel cage induction machine with 6 phases and 24 poles has been studied. Indeed, by increasing the number of poles, one can simplify or eliminate the gearbox that induces many faults while a multiphase structure allows electrical energy production when several stator phases or inverter legs are lost. For this, a precise model of the generator has been developed using the equivalent intern circuits and a parameters computing strategy that allows the determination of the parameters whatever the geometrical and electrical structure of the stator has been introduced. Associated to the power converter, this model has been simulated successfully and a field oriented control has also been inserted in the whole simulation scheme. This control strategy allows tuning of the transformation matrices and also PI regulators parameters as function of the fault and therefore is robust against electrical parameters changes. Indeed, the on-line adaptation lets to reduce significantly the power ripples that appear when one or more phases are lost. To validate the proposed method that have been previously simulated, the same test have been carry out successfully on a 24 kW prototype that is a picture, at scale 1/100, of a real advanced wind turbine connected to the grid

<p>The project consists on the reconstruction of an old and obsolete hydropower plant situated in Ockelbo (Sweden). To carry out this goal it is done firstly a land survey on the place and a preliminary study of which kind of plant should be installed. After that it is done the management part of the project, summarized in the three documents called Business Case, Project Directive and Project Specification. These papers must be written before start running any project.</p><p> </p><p>Before start writing the real project, it is explained a short background of hydropower plants and all their components, the current situation of the site studied and also the status of this green energy in Sweden. The name of the site where it is going to be placed the hydropower plant is Wij Trädgårdar and they want to make this area as an example of sustainability with different kind of green energy production.</p><p> </p><p>Any project must have a pre-study to assure that the task is possible. The theoretical part explains this pre-study, looking at the best turbine and generator with the conditions given by the land survey. This part also gives an overview of the importance to manage a project, how to do it and people who take part on it.</p><p> </p><p>Finally, on the part of the results, the theoretical installation that should be placed with its specifications is defined and also the amount of energy that it can produce. In addition, on the management part, there is concluded how to erect the new installation with the final solution given and those suppliers that will participate on the construction. Also, an economical study is included. The three management documents are added on the appendixes.</p>

This thesis presents a performance evaluation of a micro horizontal axis wind turbine, investigates the use of particle image velocimetry (PIV) to capture the flow field around a rotating blade and to track water droplets in the flow. The testing was done in a low speed wind tunnel in a highly blocked configuration. The turbine was instrumented to measure rotational speed of the rotor, axial thrust and power output. Wind speed of the wake was measured with a Kiel probe. Performance characteristics were calculated and compared with the manufacturer’s published data and to power predictions by axial momentum theories. The turbine was shown to perform well and the manufacturer’s published data are accurate. Axial momentum theory over-predicts power by approximately 50%. It is shown that good PIV results can be obtained using a fog machine to seed the flow. Improved illumination and optics will be required to measure 3D flow close to the blade. Water droplets can be tracked but a shadowgraphy arrangement should be used to better visualize the droplets. The droplets also affect the rotational speed of the rotor such that capturing the blade in a consistent point in the field of view is problematic.

Serpentine ducts used by both military and commercial aircraft can generate significant flow angularity (inlet swirl) and total pressure distortion at the engine face. The impact of inlet swirl on the engine performance and operability must be quantified to ensure safe operation of the aircraft and propulsion system and to define installed deficiencies. Testing is performed over a wide range of flight conditions in the propulsion system flight envelope in order to quantify these effects. Turbine engine compressor models are based on experimental data which can be collected at a limited number of discrete operating points. These models can be used as an analysis tool to optimize the engine test plan and help during validation of the design. The Dynamic Turbine Engine Compressor Code (DYNTECC) utilizes parallel compressor theory and quasi-one-dimensional Euler equations to determine compressor performance. In its standard form, DYNTECC uses user-supplied characteristic stage maps in order to calculate stage forces and shaft work for use in the momentum and energy equations. These maps are typically developed using experimental data. These maps can also be created using characteristic codes such as the 1-D Mean Line Code or the 2-D Streamline Curvature Code. The 1-D Mean Line Code was originally created to predict the performance of individual compressor stages and requires greatly reduced computational time when compared to 2-D and 3-D models. This thesis documents work done to incorporate the 1-D Mean Line code into DYNTECC as a subroutine. The combine DYNTECC/1-D Mean Line Code was then used to analyze the effects of inlet swirl on the fan performance and operability of the Honeywell F109 turbofan engine. The code was calibrated and validated using the F109 cycle deck. Additional code validation was performed using experimental data gathered at the United States Air Force Academy. F109 fan maps were developed for various cases of inlet swirl and results were presented showing shifts in corrected mass flow, fan pressure ratio and fan stability limit.

<p>Power generation using wind turbines is a highly researched control field.</p><p>Many control designs have been proposed based on continuous-time models</p><p>like PI-control, or state observers with state feedback but without special</p><p>regard to robustness to model uncertainties. The aim of this thesis was to</p><p>design a robust digital controller for a wind turbine.</p><p>The design was based on a discrete-time model in the polynomial framework</p><p>that was derived from a continuous-time state-space model based on</p><p>data from a real plant. A digital controller was then designed by interactive</p><p>pole placement to satisfy bounds on sensitivity functions.</p><p>As a result the controller eliminates steady state errors after a step</p><p>response, gives sufficient damping by using dynamical feedback, tolerates</p><p>changes in the dynamics to account for non linear effects, and avoids feedback</p><p>of high frequency un modeled dynamics.</p>

The temperature of the flow entering a high-pressure turbine stage is inherently non-uniform, as it is produced by several discrete, azimuthally-distributed combustors. In general, however, industrial simulations assume inlet temperature uniformity to simplify the preparation process and reduce computation time. The effects of a non-uniform inlet field on the performance of a commercial, transonic, single-stage, high-pressure, axial turbine with a curved inlet duct have been investigated numerically by performing URANS (Unsteady Reynolds-Averaged Navier-Stokes equations) simulations with the SST (Shear Stress Transport) turbulence model. By adjusting the alignment of the experimentally-based inlet temperature field with respect to the stator vanes, two clocking configurations were generated: a vane-impinging (VI) case , in which each hot streak impinged on a vane; and a mid-pitch (MP) case, in which each hot streak passed between two vanes. In the VI configuration, the hot streaks produced higher time-averaged heat load on the vanes and lower heat load on the blades. As the hot streaks in the VI case passed over the stator vanes, they also spread spanwise due to the actions of the casing passage vortices and the radial pressure gradient; this resulted in a stream entering the rotor with relatively low temperature variations. The hot streaks in the MP case were convected undisturbed past the relatively cool vane section. Relatively high time-averaged enthalpy values were found to occur on the pressure side of the blades in the MP configuration. The non-uniformity of the time-averaged enthalpy on the blade surfaces was lower in the VI configuration. The flow exiting the rotor section was much less non-uniform in the VI case, but differences in calculated efficiency were not significant. / Pratt & Whitney Canada, NSERC

As international growth in wind energy steadily increases and the world gradually moves away from fossil fuels, advanced computational tools are required to produce accurate and fast predictions in wind turbine performance, and to allow efficient design cycles using advanced materials and manufacturing methods. Currently, aerostructural analysis often employs the relatively fast but inaccurate Blade Element Momentum (BEM) theory, while accurate but slower Computational Fluid Dynamics (CFD) methods are generally used for aerodynamic analysis alone.To bridge the gap between speed and accuracy, a 3D panel code, TriPan, was coupled with an advanced structural Finite Element Method (FEM) code, TACS, to perform aerostructural analysis for wind turbine blades. In addition, the framework allows the replacement of the panel solver by higher fidelity solvers to increase the accuracy of the overall aerostructural solution.

As international growth in wind energy steadily increases and the world gradually moves away from fossil fuels, advanced computational tools are required to produce accurate and fast predictions in wind turbine performance, and to allow efficient design cycles using advanced materials and manufacturing methods. Currently, aerostructural analysis often employs the relatively fast but inaccurate Blade Element Momentum (BEM) theory, while accurate but slower Computational Fluid Dynamics (CFD) methods are generally used for aerodynamic analysis alone.To bridge the gap between speed and accuracy, a 3D panel code, TriPan, was coupled with an advanced structural Finite Element Method (FEM) code, TACS, to perform aerostructural analysis for wind turbine blades. In addition, the framework allows the replacement of the panel solver by higher fidelity solvers to increase the accuracy of the overall aerostructural solution.

The temperature of the flow entering a high-pressure turbine stage is inherently non-uniform, as it is produced by several discrete, azimuthally-distributed combustors. In general, however, industrial simulations assume inlet temperature uniformity to simplify the preparation process and reduce computation time. The effects of a non-uniform inlet field on the performance of a commercial, transonic, single-stage, high-pressure, axial turbine with a curved inlet duct have been investigated numerically by performing URANS (Unsteady Reynolds-Averaged Navier-Stokes equations) simulations with the SST (Shear Stress Transport) turbulence model. By adjusting the alignment of the experimentally-based inlet temperature field with respect to the stator vanes, two clocking configurations were generated: a vane-impinging (VI) case , in which each hot streak impinged on a vane; and a mid-pitch (MP) case, in which each hot streak passed between two vanes. In the VI configuration, the hot streaks produced higher time-averaged heat load on the vanes and lower heat load on the blades. As the hot streaks in the VI case passed over the stator vanes, they also spread spanwise due to the actions of the casing passage vortices and the radial pressure gradient; this resulted in a stream entering the rotor with relatively low temperature variations. The hot streaks in the MP case were convected undisturbed past the relatively cool vane section. Relatively high time-averaged enthalpy values were found to occur on the pressure side of the blades in the MP configuration. The non-uniformity of the time-averaged enthalpy on the blade surfaces was lower in the VI configuration. The flow exiting the rotor section was much less non-uniform in the VI case, but differences in calculated efficiency were not significant. / Pratt & Whitney Canada, NSERC