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Bijl, H.J. (author)
Wind turbines are growing bigger to becomemore cost-efficient. This does increase the severity of the vibrations that are present in the turbine blades, both due to predictable effects like wind shear and tower shadow, and due to less predictable effects like turbulence and flutter. If wind turbines are to become bigger and more cost-efficient,...
doctoral thesis 2018
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Gunes, Bilal (author)
doctoral thesis 2018
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Bos, R. (author)
Wind turbines are the largest rotating machines on the planet, operating in some of the most remote and hostile areas. During a lifespan of several decades, they have to withstand storms, waves, and gusts (and preferably produce electricity in the process). Yet, designers cannot make them too strong. Every additional kilogram of mass has to be...
doctoral thesis 2017
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Jarquin Laguna, A. (author)
The work presented in this thesis explores a new way of generation, collection and transmission of wind energy inside a wind farm, in which the electrical conversion does not occur during any intermediate conversion step before the energy has reached the offshore central platform. A centralized approach for electricity generation is considered...
doctoral thesis 2017
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Holtslag, M.C. (author)
Far offshore atmospheric conditions are favourable for wind energy purposes since mean wind speeds are relatively high (i.e., high power production) while turbulence levels are relatively low (i.e., less fatigue loads) compared to onshore conditions. Offshore wind energy, however, is still expensive compared to onshore wind energy. There is...
doctoral thesis 2016
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Gillebaart, T. (author)
One of the solutions to speed up the energy transition is the smart rotor concept: wind turbine blades with actively controlled Trailing Edge Flaps. In the past decade feasibility studies (both numerical and experimental) have been performed to assess the applicability of smart rotors in future design strategies and the next step is the...
doctoral thesis 2016
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Shariat Torbaghan, S. (author)
The new energy policy of the European Union (EU) with the core objectives of competitiveness, reliability and sustainability, has driven Europe into a transition towards a low carbon & sustainable electricity supply systems. Under the new policy, the European energy systems are pursing two major objectives. First is to shift the focus from...
doctoral thesis 2016
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Bernhammer, L.O. (author)
Wind turbines convert kinetic energy of the wind into electrical energy. Unfortunately, this process is everything but constant, as the wind source shows large fluctuations with high and low frequencies. This turbulence, together with the wind shear and yawed inflow, excites the turbine structure, thereby driving the loads and the design of...
doctoral thesis 2015
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Van Solingen, E. (author)
In the past decades wind energy has evolved into a mature source of sustainable energy such that onshore wind turbines have become cost competitive with other fossil-based energy sources. Onshore wind energy, however, faces social resistance and a lack of available locations. Offshore wind energy, on the other hand, offers vast amounts of...
doctoral thesis 2015
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Gebraad, P.M.O. (author)
Each wind turbine in a cluster of wind turbines (a wind power plant) can influence the performance of other turbines through the wake that forms downstream of its rotor. The wake has a reduced wind velocity, since the turbine extracts energy from the flow, and the obstruction by the wind turbine rotor causes increased turbulence. If another...
doctoral thesis 2014
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Mast, E.H.M. (author)
The aim of this study is to develop a method to identify the barriers to and opportunities in the development of large-scale offshore wind energy in the Netherlands, taking into account the uncertainties of the future and consequences of decisions, from technological, economical, social, political and environmental perspectives. The research...
doctoral thesis 2014
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Zaaijer, M.B. (author)
To date, the technical feasibility of making electricity from offshore wind energy has been convincingly proven. However, the current challenge is to reduce the costs of this form of energy. One of the aspects playing a role in cost reduction is the optimisation of the wind turbine. The wind turbine influences the costs of various elements of an...
doctoral thesis 2013
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Diepeveen, N.F.B. (author)
Offshore wind energy is currently characterized by the high costs associated with installation and operation. Gearboxes in particular have been singled out as a key source of the high maintenance costs of offshore wind farms. For a given wind speed, the torque of the rotor increases cubically with the diameter of its swept area. As the maximum...
doctoral thesis 2013
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Simao Ferreira, C.J. (author)
The analysis, modeling and design of the lift-driven Vertical Axis Wind Turbine (VAWT) has challenged the wind energy community for many decades; this limited progress in knowledge has severely impaired the development of the VAWT, giving rise to the myth that the VAWT rotor is inherently inefficient (in comparison with the more conventional...
doctoral thesis 2009
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Zhou, Y. (author)
As power capacities of single wind turbine, single wind park and total wind power installation are continuously increasing, the wind power begins to challenge the safety operation of the power system. This thesis focuses on the grid integration aspects such as the dynamic behaviours of wind power during disturbances, and dynamic behaviours of...
doctoral thesis 2009
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Bierbooms, W.A.A.M. (author)
doctoral thesis 2009
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Djairam, D. (author)
Wind energy is converted to electrical energy by letting the wind move charged particles against the direction of an electric field. The advantage of this type of conversion is that no rotational movement, which occurs in conventional wind turbines, is required. An electrostatic wind energy converter (EWICON) has been developed. Charged...
doctoral thesis 2008
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Holierhoek, J.G. (author)
doctoral thesis 2008
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Van Wingerden, J.W. (author)
Active control is becoming more and more important for the wind energy community. If we compare the 'old' stall regulated turbines with today's individual pitch controlled turbines we see that the loads can be considerably reduced, leading to lighter or larger turbines. However, limited actuator bandwidth and component fatigue impose significant...
doctoral thesis 2008
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Nijssen, R.P.L. (author)
Wind turbine rotor blades are subjected to a large number of highly variable loads, but life predictions are typically based on constant amplitude fatigue behaviour. Therefore, it is important to determine how service life under variable amplitude fatigue can be estimated from constant amplitude fatigue behaviour. A life prediction contains...
doctoral thesis 2006
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