L'objectif de cette thèse est de contribuer au développement de l'énergie éolienne au Liban et des problèmes de stockage qui y sont liés. Une analyse des caractéristiques du vent dans 14 sites libanais a été effectuée dans le but de sélectionner les sites optimaux pour l'implantation d'éoliennes. Après la sélection de ces cinq sites optimaux, le choix de l'éolienne adéquate et la détermination du nombre d'éoliennes qui pourrait être érigées dans chacun de ces cinq sites, une évaluation du potentiel éolien a été réalisée afin d'estimer la quantité d'électricité qui pourrait être produite par ces éoliennes. Les résultats montrent qu'il y a un excédent d'électricité produite par les éoliennes qui pourrait être enregistré pendant la nuit, ce qui nous a incités à travailler sur la conception et le dimensionnement d'un système de stockage hydraulique de l'énergie éolienne afin d'optimiser sa pénétration dans le réseau. Les cinq sites sélectionnés pour l'implantation d'éoliennes au Liban ont été soumis à la procédure d'évaluation et d'examen des impacts sur l'environnement, notamment sur le paysage et les oiseaux, ce qui aide à faciliter l'élaboration des projets prenant en compte tous les enjeux environnementaux. A la fin du travail, des pistes d'élaboration d'un règlement pour l'implantation d'éoliennes au Liban et une analyse économique du projet d'implantation d'éoliennes et d'un système de stockage ont été menées. / The objective of this thesis is to investigate of the development of the wind power in Lebanon and storage related issues. An analysis of wind characteristics at 14 Lebanese sites was carried out in order to select the optimal sites for the implementation of wind turbines. After the optimization procedure (5 sites in final), the choice of the appropriate wind turbine (in terms of capacity) and the determination of the number of wind turbines that could be erected in each of selected sites, an evaluation of the wind potential has been performed to estimate the level of electrical power that could be produced. The results show that there is an overproduction of electricity could be registered during the night, which prompted us to work on the design and dimensioning of a hydraulic storage of wind energy system to optimize its penetration into the grid. The five selected sites for the installation of wind turbines in Lebanon were subjected to the evaluation process and review of environmental impacts, particularly regarding landscape and birds, which helps to facilitate project development taking into account all environmental issues. At the end of the work, tentative regulations to erect wind turbines in Lebanon and an economic analysis of the wind project and implementation of a storage system have been proposed. / Doctorat en Sciences de l'ingénieur et technologie / info:eu-repo/semantics/nonPublished

This thesis validates SIMLOX as a simulation tool for wind energy operation and maintenance (O&M). SIMLOX have been used for modeling O&M in other sectors since 2002 but have recently begun to be used for simulating wind energy. This study validates SIMLOX for the newly introduced sector by creating a model of an existing offshore wind farm. The model used real historical data as input and the output was compared to real system response quantities (SRQs). Example of SRQs which were compared was time based availability, energy based availability, energy production, weather days, and item replacements. The study showed that SIMLOX is very well suited for this type of studies. It also showed that the major difficulty lies in obtaining proper input data. All models simulated the exact right number of major item replacements. The time based availability was considered to be the most important SRQ. The time based availability turned out to be between 0.11 - 0.66 percentage points too high compared to reference data. This most certainly depended on an overestimated work schedule for the technicians. Validation is the process of determining the degree to which a model is an accurate representation of the real world from the perspective of the intended uses of the model. This report presents all necessary knowledge to validate SIMLOX as a tool for wind energy simulations but it is thus up to the user to decide whether or not the output is accurate enough for their intended use.

In this study, an innovative solution is examined for transmission problems and frequency control for wind Turbines. Power electronics and the gear boxes are the parts which are responsible of a significant amount of failures and they are increasing the operation and maintenance cost of wind turbines. Continuously transmission (CVT) systems are investigated as an alternative for conventional gear box technologies for wind turbines in terms of frequency control and power production efficiency. Even though, it has being used in the car industry and is proven to be efficient, there are very limited amount of studies on the CVT implementation on wind turbines. Therefore, this study has also an assertion on being a useful mechanical analyse on that topic. After observing several different types of possibly suitable CVT systems for wind turbines; a blade element momentum code is written in order to calculate the torque, rotational speed and power production values of a wind turbine by using aerodynamic blade properties. Following to this, a dynamic model is created by using the values founded by the help of the blade element momentum theory code, for the wind turbine drive train both including and excluding the CVT system. Comparison of these two dynamic models is done, and possible advantages and disadvantages of using CVT systems for wind turbines are highlighted. The wind speed values, which are simulated according to measured wind speed data, are used in order to create the dynamic models, and Matlab is chosen as the software environment for modelling and calculation processes. Promising results are taken out of the simulations for both in terms of energy efficiency and frequency control. The wind turbine model, which is using the CVT system, is observed to have slightly higher energy production and more importantly, no need for power electronics for frequency control. As an outcome of this study, it is possible to say that the CVT system is a candidate of being a research topic for future developments of the wind turbine technology.

The recent worldwide economic crisis, climate change and global warming have emphasized that the need for low carbon emissions while also ensuring the economic feasibility. In this paper, wind power potential of ETD in KTH was investigated. The technical and economical feasibility of tower mounted small scale standalone wind turbine installation is conducted. The potential of wind power production was statistically analysed. The average wind speed data of four-season interval of one year period (2011) which its measurement was taken on the roof top of the ETDB, and this was adopted and analysed in order to find out the potential of wind power generation. The Rayleigh distribution probability was applied to calculate the wind speed distribution at KTH, by doing so the annual wind power potential at the area and annual energy production of the chosen wind turbine was estimated, after the selection of a proper wind turbine have been made upon the site conditions. Therefore, the study result shows that installation of the wind turbine at 24 meters hub height for this particular area will have a better performance of annual energy production, capacity factor, carbon savings and better economical value than the current turbine installed at 17 meters height at the ETD. The economic evaluation shows that the turbine can save an electricity bill of US$3661.05 per year and cover 1.84% of the electricity consumption of the ETD by reducing its respective CO2 emission from the electricity use at the department. Moreover, the payback period of the turbine installation with the inclusion of the green certificate is approximately 14 years which is more feasible if it is considered for small wind turbines too, which is already in practice for renewables including wind power in Sweden.

This study aims to perform a feasibility study on the DTU 10MW-RWT wind turbine blades constructed in the fossil-free high-strength steel 1300 MPa from SSAB. The acceptance criteria, on which the study is based, are taken from the DTU composite wind turbine model. A maximum weight of 41 000kg and a maximum tip displacement of 12.5 m are chosen. By fulfilling the acceptance criteria, the results of this study could contribute to a more sustainable future by decreasing the carbon dioxide emissions of wind turbine blades and improving their  recycling options. To perform weight optimization the Finite Element Analyses software Abaqus and the optimization software Tosca Structure are used.  The study is conducted based on Design for Six Sigma (DFSS) up until the design concept SG2. The study results in a preliminary design of the wind turbine blade constructed in SSAB Strenx 1300 and proofs that Tosca is a suitable software for performing weight optimization. The results show that it would be feasible to replace the wind turbine blades with SSAB Strenx 1300 MPa, but it will result in a weight increase for the current design. For further studies, it is recommended to consult with the stakeholders on how much weight increase of the blade is acceptable and study on how to modify the design of the steel wind turbine blade.

Det här examensarbete har genomförts i samarbete med Sweco Sverige AB på enheten för byggkonstruktion. Syftet med studien var att undersöka tungbetong som ett alternativ till konventionell konstruktionsbetong vid gjutning av vindkraftsfundament. I den här studien har ett vindkraftsfundament i konventionell konstruktionsbetong stått som grund för de dimensioneringsberäkningar som har utförts för att istället kunna använda tungbetong i fundamentet. Ett mål med studien var att med ett fundament i tungbetong minska dimensionerna och således minska klimatpåverkan och kostnaden.  För att undersöka om målet kunde uppnås har beräkningar för fundamentets geometri, krav vid bruksgränstillståndet, ekonomiska data och klimatpåverkan utförts. Från studiens dimensioneringsberäkningar om fundamentets geometri framgår det att fundamentet behöver uppfylla vissa krav på mått och därav är fundamentets radie den parameter som kan minska volymen mest. Det ledde till att volymen på fundamentet i tungbetong blev mindre än den för konventionell konstruktionsbetong.  Tungbetongens resultat blev ur vissa perspektiv bättre än konventionell konstruktionsbetong. Volymen för tungbetongsfundamentet kunde reduceras med 14 %. Detta resulterade i en minskning av koldioxidutsläpp med 7 %, priset ökade däremot med 65 %.  Genom att i detta fall använda sig av tungbetong istället för konventionell betong kunde både volym och koldioxidutsläpp reduceras, däremot till ett väldigt högt pris. / The purpose of the study was to investigate an alternative to conventional construction concrete. In this study, a wind turbine foundation consisting of conventional construction concrete have been analysed and served as a basis for dimension calculations to the foundation of heavy weight concrete.  A goal with the study was to decrease the dimensions of the foundation using heavy weight concrete instead of conventional and therefore also reduce the climate impact as well as the cost of the foundation.  To investigate if the goal is achievable, calculations for the foundation geometry, the requirement of the service limit state, economic data and climate impact have been calculated. In the calculations about the foundation geometry, certain requirements regarding the dimensions needs to be achieved and therefore it is the radius of the foundations that can affect the volume the most. This resulted in a decrease of volume for the heavy weight concrete foundation.  In some perspectives, the heavy weight concrete had better outcome than conventional construction concrete. The volume of the foundation could be reduced by 14 %. This led to a reduction in product emission by 7 %. The price of heavy weight concrete, per cubic meter, is almost five times more expensive than it is for conventional construction concrete and therefore the price was 65 % higher.  This concludes in a possibility to reduce both the volume as well as the CO2-emissions but for a very high price.

No description available.

Bei eigengekühlten Elektromaschinen in Außenläuferbauweise resultiert aus der schwierigeren Abführung der Statorverluste üblicherweise eine Reduktion der elektromagnetischen Ausnutzung. Im Beitrag wird am Beispiel eines permanentmagnetisch erregten Synchrongenerators für eine Kleinwindenergieanlage das Verfahren der intensivierten Statorrohrinnenkühlung unter Nutzung der Windströmung durch einen im Statorrohr angeordneten Kühlkörper diskutiert. Neben der elektromagnetischen und strömungsmechanischen bzw. thermischen Modellierung wird die experimentelle Trennung der Einzelverluste vorgestellt. Es wird gezeigt, dass die Ausnutzung der Maschine durch die intensivierten Statorrohrinnenkühlung um ca. 40 % gesteigert werden kann. / For self-ventilated electrical machines in outer rotor design, the difficult dissipation of stator losses usually results in a reduction of the electromagnetic utilization. Based on an example of a permanent magnet synchronous generator for a small wind turbine, the method of intensified inner stator tube cooling using the wind flow through a heat sink arranged in the stator tube is discussed in the article. In addition to the electromagnetic and fluid mechanical as well as thermal modeling, the experimental separation of the losses is presented. It is shown that the utilization of the machine can be increased by approx. 40 % by means of the intensified internal cooling of the stator tube.

Die vorliegende Arbeit beschäftigt sich mit der Anwendung der indirekten Methoden zur automatisierten Lösung von einer bestimmten Klasse von Optimalen Steuerungsproblemen im Rahmen einer modellprädiktiven Regelung für Windenergieanlagen. In einem zweiten Teil wird der Einfluss dieser Regelungsmethode auf die Festigkeit des Triebstranges untersucht. Diese führt zu einer überproportionalen Beanspruchung und damit zu einer Reduktion der Betriebsfestigkeit. Es gilt entsprechende Randbedingungen für die der Regelung zugrunde liegenden Optimalen Steuerungsprobleme zu finden, so dass weiterhin die Energieausbeute maximiert werden kann, gleichzeitig jedoch die Beanspruchung durch die Regelung begrenzt wird.

In this thesis the Counter Rotating vertical Axis Floating Tilting wind turbine (CRAFT) has been explored by creating a simulation model in the program Simulink. The CRAFT prototype is a new type of wind turbine under development by World Wide Wind and Uppsala University with the aim to produce a large scale floating vertical axis wind turbine (VAWT) with two cone shaped counter rotating turbines. The objective of this thesis is to study the required size of the secondary generator in the CRAFT. The generator is required in order to keep both of the turbines rotating with the same but opposite rotational speed, even when the turbines are experiencing different wind loads. Further areas that are investigated are if certain parameters have a specifically high impact on the need for the secondary generator.  The objective was reached by creating a model of the prototype and implementing control algorithms for both the secondary and main generator in order to control the rotational speed of the turbines. The behaviour of the CRAFT was then simulated with different wind loads and varying parameters such as the size of the main load, the size of the power output to the secondary generator and the wing length of the lower turbine. The simulations showed that it is possible to keep the rotational speed of the two turbines equal and opposite even during turbulent wind loads with the chosen control algorithm. The simulation also showed that if a small deviation in the turbine's rotational speed is allowed, a secondary generator of only 1 kW is needed instead of the currently used 5 kW generator. It was also shown that the elongating of the lower turbine wings had a small and positive effect on the energy output of the CRAFT.