Fossil fuel is presently a major source for electricity production, but it contributes significantly to Green House Gas emissions. Wind is a promising alternative, and can potentially become a major power resource in future power systems. Wind power installations are growing significantly for producing clean energy in electric power systems. As the wind penetration continues to increase to relatively high levels, it can significantly affect the overall performance and reliability of the power system. Hence, it becomes very important to accurately model the behaviour of wind, its interaction with conventional sources and also with other wind resources connected to the power system in order to conduct a realistic assessment of system reliability and benefits from wind energy utilization. When the wind penetration levels are low, all the wind energy generated is utilized to serve the load. However, at higher wind penetration levels, wind energy is spilled due to limitations in the operating reserve or ramping capability of the scheduled generating units. The system reliability and the wind energy benefits are reduced as the wind energy spillage increases due to wind curtailment. Hence, accurate wind models should be researched and developed to include wind energy curtailment in the reliability modelling, considering factors such as the system load level, priority loading order of the generating unit and response rates of the generating units. Researchers have not incorporated these factors in wind power modelling and in the adequacy evaluation of wind integrated power systems. A new analytical technique is developed in the subsequent chapters to carry out a comprehensive wind absorption capability evaluation of the power system, and also to incorporate this characteristic in reliability modelling of the system. Wind curtailments can take place not only due to generation constraints, but also due to transmission line constraints depending on the capacity and location of the wind energy resource in the power system, and the power transfer capacity of the transmission lines connected to the wind farm bus. Therefore, reliability modelling of the power system considering wind curtailments due to both generation and transmission constraints should be carried out to assess the impact of wind farms on bulk system reliability and the wind energy benefits. Wind curtailment is incorporated in the composite power system reliability evaluation by modelling the wind resource both as generation and as negative load. The techniques can be utilized to conduct system adequacy and wind energy benefit assessment both at the capacity planning stages and composite generation/transmission planning stages, incorporating wind power curtailment due to generating unit response limitations. As the wind penetration in a power system increases, the wind farms connected to the system are distributed at different geographical locations. Both analytical and Monte Carlo Simulation based techniques have previously been used by the research group at the University of Saskatchewan to include the cross correlation between the wind characteristics of different wind farms in the wind modelling for reliability evaluation of power systems. However, the combined effect of wind diversity and wind curtailments due to both transmission and generation constraints on the system reliability and wind energy benefit assessment has not been considered. The techniques developed for system adequacy and wind energy benefit assessment considering wind curtailment due to generation and transmission constraints are further modified and presented in this thesis to include wind diversity in the analysis. The developed techniques for adequacy evaluation of wind integrated power systems considering wind power curtailment and diversity should be extremely useful for system planning engineers and policy makers as wind power penetration in power systems continues to increase throughout the world.

Στη παρούσα διπλωματική εργασία γίνεται ανάλυση και μοντελοποίηση ενός μικροδικτύου, που αποτελείται από μία φωτοβολταϊκή και μία αιολική μονάδα που τροφοδοτούν ένα ωμικο-επαγωγικό φορτίο και είναι συνδεδεμένες στο δίκτυο σε κοινό κόμβο εναλλασσόμενης τάσης. Το φωτοβολταϊκό σύστημα περιλαμβάνει έναν αντιστροφέα και έναν μετατροπέα συνεχούς τάσης σε συνεχή που ανυψώνει την τάση και παράλληλα είναι ανιχνευτής του σημείου μέγιστης ισχύος, ώστε να είναι μέγιστη η παραγόμενη ισχύς του συστήματος. Το αιολικό σύστημα μεταβλητών στροφών χρησιμοποιεί μια σύγχρονη μηχανή μόνιμου μαγνήτη (PMSG) και ένα σύστημα δύο μετατροπέων, πλήρους κλίμακας, πλάτη με πλάτη. Στις εξόδους των μετατροπέων χρησιμοποιήθηκαν κατάλληλα φίλτρα RL με στόχο την μείωση του αρμονικού περιεχομένου των τάσεων και των ρευμάτων εξόδου. Έγινε προσπάθεια να εφαρμοστεί μια στρατηγική ελέγχου, ώστε να ελεγχθούν κατάλληλα τα συστήματα με σκοπό την επίτευξη μέγιστης παραγωγής ισχύος. Τέλος, υλοποιήθηκε το παραπάνω σύστημα σε περιβάλλον Matlab/Simulink και έγινε προσομοίωση για διάφορες μεταβολές στην ακτινοβολία, την ταχύτητα του ανέμου και το φορτίο. Σκοπός ήταν η μελέτη της συμπεριφοράς της δεδομένης στρατηγικής ελέγχου που εφαρμόστηκε και η εξαγωγή συμπερασμάτων. Στο πρώτο κεφάλαιο ορίζεται η κατανεμημένη παραγωγή μέσω της διαφοροποίησής της από την κεντρικοποιημένη και παρουσιάζονται οι λόγοι της πρόσφατης επανεμφάνισής της. Επίσης, αναλύονται τα πλεονεκτήματα και τα μειονεκτήματα αυτών και τέλος εισάγεται η έννοια του μικροδικτύου και τα βασικά χαρακτηριστικά του. Στο δεύτερο κεφάλαιο γίνεται αναφορά στις μονάδες παραγωγής ενός μικροδικτύου και τις διαθέσιμες τεχνολογίες. Δίνεται έμφαση στις ανεμογενήτριες, τα φωτοβολταϊκά και συστήματα συμπαραγωγής αναλύοντας τα τεχνικά χαρακτηριστικά και την αρχή λειτουργίας τους. Στο τρίτο κεφάλαιο ορίζονται οι μονάδες μετατροπής ενέργειας, δηλαδή οι ηλεκτρονικοί μετατροπείς ισχύος. Εξετάζονται οι διάφορες κατηγοριοποιήσεις αυτών και αναφέρονται τα διάφορα είδη των ημιαγωγών ισχύος από τα οποία αποτελούνται. Τέλος, αναλύονται οι τύποι των ηλεκτρονικών μετατροπέων ισχύος που χρησιμοποιήθηκαν στο υπό μελέτη σύστημα. Στο τέταρτο κεφάλαιο γίνεται η εξαγωγή των μαθηματικών εξισώσεων που περιγράφουν το σύστημα καθώς και αναλυτική περιγραφή των τεχνικών και μεθοδων που χρησιμοποιήθηκαν για τον έλεγχο. Τέλος, στο πέμπτο κεφάλαιο δίνονται τα αποτελέσματα της προσομοίωσης υπό τη μορφή διαγραμμάτων καθώς και τα συμπεράσματα της μελέτης. / In the current thesis an analysis and modeling of a microgrid is conducted. The microgrid consists of one photovoltaic and one wind unit which are feeding an R-L load and are connected in a common node to the grid. The photovoltaic system includes an inverter and a Dc to Dc converter that elevates the voltage and at the same time is a maximum power point tracker. The variable speed wind turbin uses a permanent magnet synchronous generator (PMSG) and a system of two full scale, back to back converters. Proper RL filters were used in the outputs of the converters in order to reduce the harmonic content of the voltage and current output. An attempt was made to implement a control strategy in order to control the system appropriately with the aim of achieving production of maximum power. Finally, this particular system was implemented in a Matlab/Simulink environment and simulated for various changes in radiation, wind speed and load. The aim was to study the behavior of the given control strategy applied and to come to a conclusion. In the first chapter the distributed generation is defined through its diversification from the centralized one and the reasons for its recent revival are presented. In addition, the advantages and disadvantages of these are analyzed, and finally the concept of microgrid is introduced along with its main characteristics. In the second chapter a reference of the production units of a microgrid and the available technologies is made. Emphasis is placed on wind turbines, photovoltaic and cogeneration systems by analyzing their technical features and their principal of operation. In the third chapter there is the specification of the energy conversion units, namely the electronic power converters. Their various classifications are examined and the different types of power semiconductors of which they consist are mentioned. Finally, there is an analysis of the types of converters used in the system being tested. In the fourth chapter the extraction of the mathematical equations that describe the system is made, along with a detailed description of the techniques and methods used for its control. Finally, in the fifth chapter the results of the simulation are provided in the form of diagrams along with the conclusions of the study.

The purpose of this thesis is to investigate the development of new technologies in the energy industry and to explore how it is possible for these technologies to compete with incumbent technologies in a mature market. The pursuit of renewable energy has been at the forefront of national government and international institutional policy in recent years due to the desire to improve the security of energy supply and to reduce CO2e emissions. This thesis aims to contribute to this policy debate, particularly by focussing on the issue of governmental support for infant energy technologies. In order to conduct this investigation, two main topics have been analysed. Firstly, learning curves have been studied to establish whether support for new technologies can be justified by the potential cost reductions which arise from learning-by-doing. This research evolved into the investigation of econometric issues which affect learning curves. Patent counts are used to demonstrate an alternative output-based measurement of industry wide knowledge stock, which is used as a proxy for innovation. This alternative specification of knowledge stock corroborates recent findings in the literature, that learning curves which model cost using only cumulative capacity leads to the over-estimation of cost reductions from learning-by-doing and the failure to capture cost reductions resulting from innovation. This suggests that government support for infant technologies should form a dual strategy of incentivising the deployment of generators as well as encouraging innovation, instead of using feed-in tariffs or renewable obligations which narrowly focus on increasing deployment. A great deal of progress has been made in identifying further econometric problems affecting learning curves in recent years. In the progress of this study, it was identified that cumulative capacity, the cost of wind power and knowledge stock are all non-stationary time series variables. The hypothesis that these variables are cointegrated was rejected by the Westerlund test, which implies that learning curves produce spurious results. This has major consequences for government policy as it suggests that learning curves should not be used to justify support for infant technologies. Secondly, a choice experiment was conducted to determine Scottish households’ willingness to pay for electricity generated from renewable sources compared to conventional sources such as coal, oil and gas. A labelled choice experiment was used to determine whether households have preferences between onshore wind power, offshore wind power and wave power. The results of a latent class model reveal that the majority of households (76.5%) are willing to pay an additional £89-£196 per year to obtain electricity from renewable resources instead of conventional sources. However, there is no statistically significant difference in the willingness to pay between the renewable technologies included in the choice experiment. The latent class model also illustrated that there is a sizeable minority (23.5%) who are opposed to renewable energy development. Older respondents and those less concerned about CO2 emissions are significantly more likely to form part of this group at the 5% level of significance. The study also included a unique addition by identifying households which purchased a house in the previous seven years. Interacting the actual transaction prices of these houses in a multinomial logit model suggested that households may be concerned about renewable energy developments devaluing their properties or the additional expense required to power larger houses. Due to the increasing difficulty of conducting choice experiments in the UK, a novel method of eliciting choice experiment responses from online advertising was tested and was found to be a cost-effective method of eliciting choice experiment responses. Overall, the research indicates that caution should be exercised when interpreting the results of a choice experiment which elicits responses using Internet advertising. It can be observed that the pseudo R2 of the Internet-based sample is lower than the mail-based sample and that the mean respondent to the Internet-based choice experiment is willing to pay significantly more for renewable electricity than the mean respondent to the mail-based choice experiment at the 5% level of significance. Furthermore, the mean willingness to pay estimate in the Internet-based choice experiment appears to be unrealistically high. Further research investigating the elasticity of survey responses to the prize fund on offer would be valuable in identifying the most cost-effective strategy to obtain responses and to generate a more representative sample.

Σε αυτή την διπλωματική θα πραγματευτούμε την μοντελοποίηση ενός υβριδικού συστήματος το οποίο θα συνδυάζει τη λειτουργία ανεμογεννήτριας και στοιχείων καυσίμου (fuel cell). Πιο συγκεκριμένα, θα δημιουργήσουμε έναν εξομοιωτή αυτού του υβριδικού συστήματος, του οποίου η λειτουργία θα είναι η εξής. Σκοπός μας είναι να χρησιμοποιήσουμε την παραγόμενη ισχύ από ανεμογεννήτρια. Φυσικά η ισχύς αυτή θα έχει διακυμάνσεις. Έτσι άλλες φορές θα είναι επαρκής, άλλες θα είναι ανεπαρκής και άλλες θα υπάρχει περίσσεια αυτής. Με το υβριδικό σύστημα που θα αναπτύξουμε, θα μελετήσουμε πως μπορούμε να έχουμε και στις τρεις αυτές περιπτώσεις σταθερή ισχύ. Στην περίπτωση που η ενέργεια που μας δίνει ο άνεμος είναι μεγαλύτερη της επιθυμητής, χρησιμοποιούμε το πλεόνασμα (αφού το μετατρέψουμε πρώτα σε σταθερό ρεύμα) σε κυψέλες ηλεκτρόλυσης. Εκεί υπάρχει ηλεκτρολύτης στον οποίο γίνεται ηλεκτρόλυση νερού η οποία οδηγεί σε παραγωγή Υδρογόνου. Το Υδρογόνο αυτό το αποθηκεύουμε σε δεξαμενές (για αυτό το σκοπό μπορεί να χρησιμοποιηθεί και η ίδια η ανεμογεννήτρια) και μπορούμε να το χρησιμοποιήσουμε αργότερα σαν καύσιμο σε στοιχεία καυσίμου (fuel cells) όταν η ισχύς που μας δίνει η ανεμογεννήτριά μας είναι ανεπαρκής. Όσον αφορά την περίπτωση επομένως κατά την οποία δεν λαμβάνουμε αρκετή ισχύ από την ανεμογεννήτρια, διοχετεύουμε το αποθηκευμένο Υδρογόνο σε συστοιχίες fuel cells, και παράγουμε ενέργεια με βάση την αντίδραση : οπότε και συμπληρώνουμε την απαιτούμενη ενέργεια που μας λείπει για να έχουμε κάθε φορά την επιθυμητή ισχύ ασχέτως συνθηκών ταχύτητας ανέμου. Όπως είναι φανερό σε όλη αυτή την διαδικασία παραγωγής ενέργειας οι μόνες εκπομπές στο περιβάλλον είναι νερό σε υγρή ή αέρια κατάσταση. Συνεπώς μιλούμε για ένα σύστημα άκρως φιλικό προς το περιβάλλον, το οποίο στηρίζεται εξ’ ολοκλήρου σε ανανεώσιμη πηγή ενέργειας, την αιολική. / In this project we will try to explore a hybrid system. This system has a windturbine which transformes wind power to electricity, an electrolyser which uses the electricity of the windturbine in order to produce hydrogen via electrolysis of water and storage it, and a fuel cells stack in which the storage hydrogen is combined with oxygen and produces electricity and water. We will see how all these parts are combined in order to maximize the total efficiency of that system.

Despite their environmental benefits, wind farms, have attracted controversy with regard to their impacts on birds. These impacts include collision risks, direct and indirect habitat loss and barrier effects. The main objectives of this study were to determine whether the Baie-des-Sables wind farm, located on the south shore of the St-Lawrence River, is having an impact upon the spring migration of raptors. Emphasis was placed on comparing the differences between both behaviour and abundance of migrating raptors between the wind farm and a contr9l area. Three aspects of behaviour were recorded; altitude, change in direction and flight type. No significant differences were found between the wind, farm area and the control area with respect to migratory behaviour and abundance of any species. Low-lying topography and the fact most migratory raptors flew above blade height likely explain why no differences were found between the wind farm and control area.

<p>Intermittent energy resources, including wind and solar power, continue to be rapidly added to the generation fleet domestically and abroad. The variable power of these resources introduces new levels of stochasticity into electric interconnections that must be continuously balanced in order to maintain system reliability. Energy storage systems (ESSs) offer one potential option to compensate for the intermittency of renewables. ESSs for long-term storage (1-hour or greater), aside from a few pumped hydroelectric installations, are not presently in widespread use in the U.S. The deployment of ESSs would be most likely driven by either the potential for a strong internal rate of return (IRR) on investment and through significant benefits to system reliability that independent system operators (ISOs) could incentivize.</p><p>To assess the potential of ESSs three objectives are addressed. (1) Evaluate the economic viability of energy storage for price arbitrage in real-time energy markets and determine system cost improvements for ESSs to become attractive investments. (2) Estimate the reliability impact of energy storage systems on the large-scale integration of intermittent generation. (3) Analyze the economic, environmental, and reliability tradeoffs associated with using energy storage in conjunction with stochastic generation.</p><p>First, using real-time energy market price data from seven markets across the U.S. and the physical parameters of fourteen ESS technologies, the maximum potential IRR of each technology from price arbitrage was evaluated in each market, along with the optimal ESS system size. Additionally, the reductions in capital cost needed to achieve a 10% IRR were estimated for each ESS. The results indicate that the profit-maximizing size of an ESS is primarily determined by its technological characteristics (round-trip charge/discharge efficiency and self-discharge) and not market price volatility, which instead increases IRR. This analysis demonstrates that few ESS technologies are likely to be implemented by investors alone.</p><p>Next, the effects of ESSs on system reliability are quantified. Using historic data for wind, solar, and conventional generation, a correlation-preserving, copula-transform model was implemented in conjunction with Markov chain Monte Carlo framework for estimating system reliability indices. Systems with significant wind and solar penetration (25% or greater), even with added energy storage capacity, resulted in considerable decreases in generation adequacy.</p><p>Lastly, rather than analyzing the reliability and costs in isolation of one another, system reliability, cost, and emissions were analyzed in 3-space to quantify and visualize the system tradeoffs. The modeling results implied that ESSs perform similarly to natural gas combined cycle (NGCC) systems with respect to generation adequacy and system cost, with the primary difference being that the generation adequacy improvements are less for ESSs than that of NGCC systems and the increase in LCOE is greater for ESSs than NGCC systems.</p><p>Although ESSs do not appear to offer greater benefits than NGCC systems for managing energy on time intervals of 1-hour or more, we conclude that future research into short-term power balancing applications of ESSs, in particular for frequency regulation, is necessary to understand the full potential of ESSs in modern electric interconnections.</p> / Dissertation

The favorable wind recourses in many cold climate regions make them interesting for development of wind farms. However, with the cold climate come drawbacks due to icing. Production losses, fatigue loadings, ice throws and increased noise are some of the more severe issues that have to be addressed. Thus, wind power in cold climaterequires ice detectors both during the prospecting phase in the site assessment and during production for controlling of the turbines. This study aimed to evaluate six ice detector systems and their ability to detect time periods with ice and ice growth. The usability of the detector data for site assessment or controlling of the turbine was also discussed. The tested detectors were: the T 40 series from HoloOptics (HoloOptics), 0872F1 Ice Detector from Goodrich (Goodrich), LID-3300IP from Labkotec (LID), IceMonitor from SAAB Combitech (IceMonitor) and IGUS BLADcontrol from Rexroth Bosch Group (IGUS). Also a combination of the three anemometers Thies 4.3350.00.0000 from Adolf Thies GmbH &amp; Co.KG (Thies), Vaisala WAA252 from Vaisala Oyj (Vaisala) and NRG Icefree3 from NRG Systems (NRG), used for wind measurements, has been analyzed for ice detection purposes. Data from field tests in Åsele municipality in the northern part of Sweden has been processed in MATLAB. Indications of ice and ice growth have been compared between the detectors to see how often they indicate concurrently. The measurements showed that the IceMonitor and the three anemometers indicated the occurrence of ice at the same time most of the time. The detectors with the ability to detect ice growth (Goodrich, LID, T44 and T41, IceMonitor) had a lot fewer concurrent indications. The correspondence between production loss time periods and the IGUS and T41 ice and ice growth indications were also low. Thus it was concluded that periods with ice were possible to find with a decent precision while ice growth and production loss periods were hard to find with any accuracy. The biggest limitation to the detectors’ functionality was the severe icing events that either hindered the detectors from working properly or broke them completely. None of the detectors were recommended for controlling of the wind turbines. If the reliability of the detectors during the more sever icing events could be increase they could however be used for site assessment to give a rough idea of the icing climate. / De gynnsamma vindar som finns i många regioner med kallt klimat gör dem intressanta för utveckling av vindkraftparker. Men med det kalla klimatet kommer nackdelar på grund av isbildning. Produktionsförluster, utmattningslaster, iskast och ökat buller är några av de mer allvarliga problem som måste åtgärdas. Således kräver vindkraft i kallt klimat isdetektorer både under prospekteringsfasen av området och under produktion, för styrning av turbinerna. Denna studie hade som syfte att utvärdera sex isdetektorsystem och deras förmåga att upptäcka tidsperioder med is och istillväxt. Detektorernas användbarhet vid projektering eller kontroll av vindturbiner diskuterades också. De testade detektorerna var: T 40-serien från HoloOptics (HoloOptics), 0872F1 Ice Detector från Goodrich (Goodrich), LID-3300IP från Labkotec (LID), IceMonitor från SAAB Combitech (IceMonitor) och IGUS BLADcontrol från Rexroth Bosch Group (IGUS). Även en kombination av de tre anemometrarna Thies 4.3350.00.0000 från Adolf Thies GmbH &amp; Co.KG (Thies), Vaisala WAA252 från Vaisala Oyj (Vaisala) och NRG Icefree3 från NRG Systems (NRG), som används för vindmätningar, har analyserats för isdetektionsändamål. Data från fältstudier i Åsele kommun i norra delen av Sverige har behandlats i MATLAB. Indikationer på is och istillväxt har jämförts mellan detektorerna för att se hur ofta de visar samtidigt. Mätningarna visade att IceMonitor och de tre anemometrarna för det mesta indikerade förekomst av is samtidigt. Detektorerna med förmåga att detektera istillväxt (Goodrich, LID, T44 och T41, IceMonitor) hade mycket färre samtidiga indikationer. Överensstämmelsen mellan tidsperioder med produktionsbortfall, is (IGUS) och istillväxt (T41) var också låg. Således drogs slutsatsen att perioder med is var möjligt att hitta med en anständig precision emedan istillväxt och produktionsförlustperioder var svåra att hitta med någon större exakthet. Den största begränsningen av detektorernas funktionalitet var de svåra nedisningseventen som antingen hindrade detektorerna från att fungera ordentligt eller förstörde dem helt. Ingen av detektorerna rekommenderas för styrning av vindkraftverk. Om tillförlitligheten på detektorerna under de svårare nedisningseventen förbättras skulle detektorerna dock kunna användas vid projektering för att ge en ungefärlig uppfattning av isklimatet. / Vindforsk III: V-363 project

Nowadays there is no need to convince anyone about the necessity of renewable energy. One of the most promising ways to obtain it is the wind power. Countries like Denmark, Germany or Spain proved that, while professionally managed, it can cover a substantial part of the overall energy demand. One of the main and specific problems related to the wind power management — development of the accurate power prediction models. Nowadays State-Of-Art systems provide predictions for a single wind turbine, wind farm or a group of them. However, the spatio-temporal propagation of the errors is not adequately considered. In this paper the potential for improving modern wind power prediction tool WPPT, based on the spatio-temporal propagation of the errors, is examined. Several statistical models (Linear, Threshold, Varying-coefficient and Conditional Parametric) capturing the cross-dependency of the errors, obtained in different parts of the country, are presented. The analysis is based on the weather forecast information and wind power prediction errors obtained for the territory of Denmark in the year 2004. / Vienas iš perspektyviausių bei labiausiai plėtojamų atsinaujinančių energijos šaltinių - vėjas. Tokios Europos Sąjungos šalys kaip Danija, Vokietija bei Ispanija savo patirtimi įrodė, jog tinkamai valdomas bei vystomas vėjo ūkis gali padengti svarią šalies energijos paklausos dalį. Pagal Europos Sąjungos direktyvą 2001/77/EC Lietuva yra įsipareigojusi iki 2010 m. pasiekti, kad elektros energijos gamyba iš atsinaujinančių energijos išteklių sudarytų 7% suvartojamos elektros energijos. Šių įsipareigojimų įvykdymui Lietuvos vyriausybės priimtu nutarimu yra nustatyta atsinaujinančių energijos išteklių naudojimo skatinimo tvarka, pagal kurią numatyta palaipsniui plėsti vėjo energijos naudojimą šalyje. Planuojama, kad iki 2010 m. bus pastatyta 200 MW bendros galios vėjo elektrinių, kurios gamins apie 2,2% visos suvartojamos elektros energijos [Marčiukaitis, 2007]. Didėjant vėjo energijos daliai energetikos sistemoje, Lietuvoje ateityje kils sistemos balansavimo problemų dėl nuolatinių vėjo jėgainių galios svyravimų. Kaip rodo kitų šalių patirtis, vėjo elektrinių galios prognozė yra efektyvi priemonė, leidžianti išspręsti šias problemas. Šiame darbe pristatyti keletas statistinių modelių bei metodų, skirtų išgaunamos vėjo energijos prognozėms gerinti. Analizė bei modeliavimas atlikti nagrinėjant Danijos WPPT (Wind Power Prediction Tool) duomenis bei meteorologines prognozes. Pagrindinis darbo tikslas - modifikuoti WPPT, atsižvelgiant į vėjo krypties bei stiprio įtaką energijos... [toliau žr. visą tekstą]

Darbas susideda iš dviejų dalių teorinės bei praktinės. Darbo tikslas – įvertinti vėjo parametrus ir prognozuojamą vėjo elektrinių galią pajūrio ir Tauragės regionams. Teorinėje dalyje aprašoma vėjo energetikos pasiekimai ir perspektyvos Lietuvoje, aptariami vėjo srautų kitimo atmosferos pasienio sluoksnyje dėsningumai, vėjo prognozavimo metodai, vėjo jėgainių konstrukcija ir veikimo principas. Praktinėje dalyje pateikiama vėjo matavimo duomenų statistinė analizė, bei įvertinamas prognozuojamas metinis vėjo jėgainių pagamintos energijos kiekis. / The work consists of two parts: theoretical and practical. The aim of the work is to evaluate the parameters of the wind and prognosticated the power of wind- power- stations for near- shore zones and regions of Tauragė. In the theoretical part the achievements and perspectives of wind energetics in Lithuania are described, the regularity of wind flow changes in atmosphere terminal are discussed, the methods of wind prognostication, the construction and working principle of wind- power- stations. In the practical part the statistical analysis of wind measures is shown and the prognosticated amount of energy produced by wind- power- stations per year is evaluated.

Šiame darbe nagrinėjamas vėjo elektrinių sukeliamas įtampos mirgėjimo reiškinys, įvardijamos jo atsiradimo priežastys. Aptariama vėjo elektrinių sukelta įtaka tinklo įtampos kokybei. Taip pat nustatomas įtampos mirgėjimo poveikis elektriniams įrenginiams, žmogaus sveikatai ir aplinkai. Darbe pateikiama įtampos mirgėjimo skaičiavimo metodika vėjo elektrinės prijungimo taške. Tiriamosios dalies skaičiavimai atlikti pasirinkus Pakruojo rajone esantį 6 MW vėjo elektrinių parką. Magistro baigiamajame darbe paskaičiuotas staigusis įtampos pokytis vėjo elektrinės prijungimo taške, nuolatinis įtampos mirgėjimas, perjungimų ties pradiniu vėjo greičiu sukeltas įtampos mirgėjimas ir perjungimų ties vardiniu vėjo greičiu sukeltas įtampos mirgėjimas. Skaičiavimai atlikti vėjo elektrinių parkui, prijungtam prie 10 ir 35 kV elektros tinklo. Darbo pabaigoje pateikiamos išvados apie tyrimo rezultatus. / In master‘s thesis analyzed wind – voltage flicker caused by the phenomenon and its causes. In the work discussed the impact of wind power operating for power voltage quality. Also determined an effect of voltage flicker for electrical equipment, humans health and enviroment. The work presents the methodology for calculating the voltage flicker of wind power at the connection point to power grid. Practical calculations of master's thesis have been made in the Pakruojis 6 MW wind power park. In the master‘s thesis calculated voltage change causes the wind power connection point of the constant voltagre flicker, switching at an initial speed of the wind-induces voltage flicker and switching at the rated speed of the wind-induced voltage flicker. The calculation was made in the wind park, connected to 10 and 35 kV power network. The end of work contains conclusions of the investigation results.