aFor many years innovation has been an integral part of improvements to products and services. Small and Medium Enterprises (SMEs) have been known as innovation generators, and their importance is paramount for the growth of economy. And yet despite their great importance, there is still a lack of understanding about how SMEs and High-tech SMEs (HTSMEs) with complex products conduct their management of innovation of New Product Development (NPD). Therefore, the purpose of this study is to provide a foundation for addressing the suggested gaps in the literature and to show that further research is needed in innovation management of NPD and how it is connected to HTSMEs. Renewable energy wind turbine sources and the potential growth they represent for SMEs was a factor in choosing this sector as the subject of this research. HTSMEs with creative ideas and innovations of complex products need to adequately manage product development. This recognises the organisation's practices and processes during NPD and the need for innovation management (IM) as a part of an organisation's capabilities in order to achieve a sustainable competitive advantage (SCA). The aim of this thesis is to explore and validate a major qualitative abductive methodology from the findings of 21 High-tech Small Medium Enterprises management in relation to complex wind turbine invention-innovation (creative destruction) practices and processes during the NPD. Analysis, synthesis, and conclusions from the findings of this study are interpreted and discussed in the context of the definition, concepts, characteristics, theoretical, and conceptual framework. Finally, implications for managerial practice offer a deeper understanding of how HTSME manage innovation practices and processes occur during NPD building a superior product and recommendations for further research that can be valuable to academics, practitioners, and other researchers who are seeking ideas for research topics are presented and discussed.

Avec l’évolution technologique, le progrès de l’électronique de puissance et surtout l’enjeu économique, l’utilisation des machines asynchrones à cages ou à rotor bobiné occupe de plus en plus de place dans tous les domaines comme les entrainements électriques et la production d’énergie, leur robustesse, leur fiabilité et leur coût moins élevé sont particulièrement appréciés. Ces deux types d’actionneur en fonctionnement générateur sont la base des éoliennes actuelles.Néanmoins, malgré les travaux de recherches effectués ainsi que les améliorations apportées, ces machines demeurent des sièges potentiels de défaillances aussi bien au niveau stator que rotor. Les défauts les plus courants qui peuvent se produire dans la génératrice asynchrone à rotor bobiné du système éolien, au niveau rotor et stator sont : a) le court circuit sur les enroulements rotoriques et statoriques, b) les défaillances de roulements, c) les irrégularités statiques ou dynamiques de l’entrefer, d) les problèmes au niveau des balais et collecteurs. Ces types de défauts doivent êtres détectés, localisés à temps car ils peuvent endommager gravement le système. Durant ces dernières années, le diagnostic des défauts affectant les systèmes éoliens a été largement étudié. Un grand nombre de méthodes est disponible visant à améliorer la conception du système, à augmenter la qualité et la production d’énergie électrique et d’en diminuer les coûts. Malgré les résultats de la recherche, ces systèmes multi-Complexes restent encore les sièges de réflexions de plusieurs laboratoires tant qu’industriels qu’académiques.Ce rapport de thèse présente une nouvelle méthodologie de diagnostic de défauts combinant la méthode à base de modèle utilisant les équations mathématiques explicites du processus et la méthode sans modèle. Les machines électriques sont modélisées analytiquement par la méthode des circuits électriques magnétiquement couplés. L’objectif est de générer des données en fonctionnement sain et en fonctionnement défaillant de ses variables d’état. Tandis que la méthode sans modèle utilisée est l’analyse en composantes principales (ACP). Les deux méthodes sont implémentées sous Matlab/ Simulink. Les données de la machine acquises sont traitées et analysées par des méthodes statistiques pour générer des résidus. La détection et la localisation de défauts sur la machine sont obtenues par l’analyse des résidus de ses variables d’état. Les résidus sont des indicateurs de défaillance ou non du système étudié. L’analyse des grandeurs caractéristiques de la machine étudiée dans ce rapport de thèse par le biais de plusieurs résultats de simulation montre l’efficacité de la méthode ACP, aussi bien sur le plan de la détection que de la localisation, par rapport aux autres méthodes de diagnostic des machines électriques. / With the technological evolution, due to the progress of power electronics and the economic issue, the use of induction machines with squirrel cage rotor or wound rotor induction machine occupies more and more places in all areas such as electric drive system and power production due to their robustness, their reliability and their lower cost which are highly appreciated. These two types of actuator in generator operation are the basis of the current wind turbine.Nevertheless, in spite of those different researches as well as those improvements, these machines remain still the potential faults both in stator and rotor levels.The most current default which may occur in the wound rotor asynchronous generator of the wind system at the rotor and stator levels are: a) Inter-Turn short circuit on the rotor and stator windings; b) The bearings failures; c) Static or dynamic irregularities of the air-Gap; d) Brushes and collectors ring problems;These types of faults must be detected and localized in time because they may damage the whole system. During these last years, the faults diagnosis affecting the wind systems was widely studied.A large number of methods are available to improve the system design, to increase the quality and quantity of the electrical energy produced and to decrease this energy production costs. In spite of the literatures research results, these multi-Complex systems still remain the reflections seats of several industrial and academic laboratories. This thesis report presents a new faults diagnosis methodology combining the method using the explicit mathematical equations model of the process and the method without a prior model of the system which is the data statistical analysis. The electrical machines are analytically modeled by the method of magnetically coupled electric circuits.The objective is to generate data in healthy and faults functioning of its variable state. Whereas the method without model used is of the principal components analysis (PCA).Both methods are implemented under Matlab /Simulink. The data of the acquired machines are handled and analyzed through the statistical method in order to generate the residues.The detection and the localization of the machine faults are obtained by the residues analysis of its variable state. Residues are faults indicators or healthy on the studied system.The analysis of the characteristic size of the machine studied in this thesis report through several simulation results shows the efficiency of the method PCA, as well as in detection and localization, when compared with other diagnosis methods of electrical machines.

Thesis (Ph. D.)--University of Nevada, Reno, 2005. / "August 2005." Includes bibliographical references (leaves 143-154). Online version available on the World Wide Web.

Among the renewable energies, wind energy presents the highest growth in installed capacity and penetration in modern power systems. This is why reliability of wind turbines becomes an important topic in research and industry. To this end, condition monitoring (or health monitoring) systems are needed for wind turbines. The core of any condition monitoring system (CMS) are fault diagnosis algorithms whose task is to provide early warnings upon the occurrence of incipient (small magnitude) faults. Thanks to the use of CMS we can avoid premature breakdowns and reduce significatively maintenance costs. The present thesis deals with fault diagnosis in sensors of a doubly-fed induction generator (DFIG) for wind turbine (WT) applications. In particular we are interested in performing fault detection and isolation (FDI) of incipient faults affecting the measurements of the three-phase signals (currents and voltages) in a controlled DFIG. Although different authors have dealt with FDI for sensors in induction machines and in DFIGs, most of them rely on the machine model with constant parameters. However, the parameter uncertainties due to changes in the operating conditions will produce degradation in the performance of such FDI systems. In this work we propose a systematic methodology for the design of sensor FDI systems with the following characteristics: i) capable of detecting and isolating incipient additive (bias, drifts) and multiplicative (changes in the sensor gain) faults, ii) robust against changes in the references/disturbances affecting the controlled DFIG as well as modelling/parametric uncertainties, iii) residual generation system based on a multi-observer strategy to enhance the isolation process, iv) decision system based on statistical-change detection algorithms to treat the entire residual and perform fault detection and isolation at once. Three novel sensor FDI approaches are proposed. The first is a signal-based approach, that uses the model of the balanced three-phase signals (currents or voltages) for residual generation purposes. The second is a model-based approach that accounts for variation in the parameters. Finally, a third approach that combines the benefits of both the signal- and the model-based approaches is proposed. The designed sensor FDI systems have been validated using measured voltages, as well as simulated data from a controlled DFIG and a speed-controlled induction motor. In addition, in this work we propose a discrete-time multiple input multiple output (MIMO) regulator for each power converter, namely for the rotor side converter (RSC) and for the grid side converter (GSC). In particular, for RSC control, we propose a modified feedback linearization technique to obtain a linear time invariant (LTI) model dynamics for the compensated DFIG. The novelty of this approach is that the compensation does not depend on highly uncertain parameters such as the rotor resistance. For GSC control, a LTI model dynamics is derived using the ideas behind feedback linearization. The obtained LTI model dynamics are used to design Linear Quadratic Gaussian (LQG) regulators. A single design is needed for all the possible operating conditions.

Wind farms are nowadays more often constructed in alpine terrain than earlier due to theprofitable wind resource as well as, often, less conflicting interests than in more denselypopulated areas. The cold climate poses a relatively new challenge to the wind power industrysince icing of the wind turbine blades and sensors may induce losses in production, increasethe wear and tear of the components, leading to a shortening of structural life time as well as itdecreases the availability and hence reducing the economical profitability for the owner.This study focuses on modelling of ice accretion on a vertically mounted cylinder,dimensioned to correspond to an IceMonitor, and comparing the results with measured iceload on a similar instrument during the winter of 2009/2010. The modelling is carried outwith both a statistical approach using multiple linear regression and a physical approach usingmodel for ice accretion. Ice load was also modelled for the period 1989-2009 using the ERAinterimre-analysis data set in order to compare the winter 09/10 with a longer referenceseries. Modelled ice loads for four winters between 2005 and 2009 were compared withproduction data to investigate a possible connection between ice load and production losses.The results showed that the statistical approach was unable in its current form toreproduce and predict measured ice loads and the method was deemed unsuitable. Thephysical model shows more promising results, although with problems in modelling rapid iceaccretion and ice shedding events.No clear connection between measured production losses and modelled ice loads wasfound when analyzing available data. Uncertainties in input data correction as well asimportance of ice density are possible sources of error.Due to confidentiality of some of the data, the measurement sites used in this thesis aredenoted site A, site B and site C.

During 2006 and 2007 behavioral observations surveys of raptors were conducted at 12 turbines of a 66-turbine wind farm near Port Burwell, Ontario, Canada. Mortality surveys were conducted at all turbines in the wind farm with additional search effort at the twelve turbines where behavioral monitoring was conducted. The wind farm is located along a significant autumn raptor migration corridor along Lake Erie which is in the area of the Central Flyway. Only one raptor fatality was found each year at the 12 turbines used in the study, with one additional fatality found at the other 54 turbines in the wind facility. The estimated mortality rate for Erie Shore Wind Farm ranged from 0.028 to 0.049 raptor fatalities/MW/autumn. The estimated mortality rate for Erie Shores is at the low end of mortality for North American wind facilities outside of California, and which are not located in known migratory pathways. My findings suggest that the presence of high numbers of migrant raptors passing over a wind facility site does not automatically equate to high collision mortality. Over 5,579 observations of individual raptor passes within 250m of a turbine were recorded. The majority of raptors (73%) passed outside of blade sweep height. The majority of raptors avoided entering the risk zone of operational turbines with 2.92% (n = 159) of raptors observed passing within the risk zone of blade sweep height above ground and 0-40m out from the turbine base. The majority (73%) of raptors that entered the risk zone did so under conditions when risk was reduced due to turbine blade orientation in relation to the raptors’ direction of movement or when the turbine was not operational.

Aeroacoustic emissions were identified as a primary concern in the public acceptance of wind turbines. A review of literature involving sound localization was undertaken and led to the design of two microphone arrays to identify acoustic sources. A small-scale array composed of 27 sensors was produced with the intention of improving the quality of sound measurements over those made by a single microphone in a small, closed-loop wind tunnel. A large-scale array containing 30 microphones was also implemented to allow for measurements of aeroacoustic emissions from airfoils and rotating wind turbines. To minimize cost and pursue alternative sensor technologies, microelectromechanical microphones were selected for the array sensors and assembled into the arrays on printed circuit boards. Characterization of the microphones was completed using a combination of calibration techniques, primarily in a plane wave tube. Array response to known sources was quantified by analyzing source maps with respect to source location accuracy, beamwidth, and root mean square error. Multiple sources and rotating sources were tested to assess array performance. Following validation with known sources, wind tunnel testing of a 600 watt wind turbine was performed at freestream speeds of 2.5 m/s, 3.5 m/s, 4.5 m/s, and to 5.5 m/s. Significant aeroacoustic emissions were noted from the turbine in the 4.5 m/s and 5.5 m/s cases, with an increase of up to 12 dB over background levels. Source maps from the 5.5 m/s tests revealed that the primary location of aeroacoustic emissions was near the outer radii of the rotor, but not at the tip, and generally moved radially outward with increasing frequency. The azimuthal location of the greatest sound pressure levels was typically found to be between 120º and 130º measured counterclockwise from the upward vertical, coinciding with the predicted location of greatest emissions provided by an analytical model based on dipole directivity and convective amplification. Analysis of the acoustic spectra, turbine operating characteristics, and previous literature suggested that the sound emissions emanated from the trailing edge of the blades.

Η παρούσα διπλωματική εργασία κάνει μια ανασκόπηση στην ενεργειακή κατάσταση του πλανήτη και της Ελλάδας. Παρουσιάζει τις εναλλακτικές-ανανεώσιμες μορφές ενέργειας παραγωγής ηλεκτρισμού. Στη συνέχεια, αναλύει τον άνεμο, τα χαρακτηριστικά μεγέθη του, την αιολική ενέργεια, και τις προοπτικές της εγχώρια. Βλέπουμε αναλυτικά τον ανεμοκινητήρα, τους διαφορετικούς τύπους του και τη λειτουργία του. Και καταλήγουμε στο να καθορίσουμε τους τρόπους αξιολόγησης μιας αιολικής εγκατάστασης, εκφράζουμε μαθηματικά τις οικονομικές σχέσεις και παραθέτουμε μια εφαρμογή αιολικής εγκατάστασης που αναλύεται με τα παραπάνω. Τέλος, αναφερόμαστε στο νομοθετικό πλαίσιο αν και ρευστό από έτος σε έτος και στην ισχύουσα διαδικασία εγκατάστασης ενός αιολικού πάρκου. / The present dissertation gives a general review of the situation of energy of the planet and Greece. It presents the alternative-renewable forms of energy for the production of electricity. Afterwards, it analyses the wind, its characteristic sizes, the wind power and its domestic perspectives. We can see in detail the wind engine , its various types and its function. Furthermore, we end up defining the ways evaluating of a wind installation, we express mathematically the financial relations and we not only cite an application of a wind installation which is analysed with the above mentioned ways but we also present the easiest analysis through the computer. Finally, we refer to the legislative scope even though it is unstable from year to year and to the procedure of installation of a wind park which is in effect.

Wind energy is a continuous, clean source of energy that can be harnessed for electricity generation or water pumping. The geographic location of Mozambique, and the long coastline renders the country a good wind energy potential that could potentially be exploited for water pumping or electrical power systems that have social and economic benefits and thereby contribute to a reduction in unsustainable practices of wood biomass burning which is the main source of energy in rural villages and high density suburbs of the main cities of the country. This study is focused on evaluating the potential of harnessing wind energy for electrical power generation in Mozambique using the Wind Atlas Analysis and Application Programme (WAsP) model. The study characterises wind speed patterns and wind frequency distributions at selected meteorological stations based on hourly observations, and models the available wind energy in coastal and interior areas. Meteorological parameters such as wind speed data from nearby meteorological stations and wind turbine characteristics were used as inputs into the model. To effectively harness wind energy, mean annual wind speeds should at least be 3 ms-1. For this reason only sites satisfying this criterion were selected. The spatial selection criteria considered a fair distribution of candidate sites such that coastal areas of the southern, northern and the interior Niassa and Nampula provinces were covered. The results of the WAsP model simulations, indicate that there is sufficient wind energy resource in both interior and coastal areas, which varies with height a.g.l., and that can be exploited for pumping water and generating electricity in small or medium electrical power systems, particularly the coastal areas of Ponta de Ouro, Mavelane, and Tofinho where the mean annual wind speed is above 5.0 ms-1 at the 10 m level and about 8.0 ms-1 at the highest levels (50 - 60 m a.g.l.) and interior area of Lichinga (mean annual wind speed of about 6 ms-1 at the same highest levels). The lowest wind energy potential (mean annual wind speed of about 4.0 ms-1) is found in the Nampula area. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2012.

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