The emergence of wind energy as a potential alternative to traditional sources of fuel has prompted notable research in recent years. One primary factor contributing to efficient utilization of wind energy from a wind farm is the type of turbines used. However, selection of a specific wind turbine type is a difficult task due to several criteria involved in the selection process. Important crit...

It is now widely accepted that a shift towards renewable energy production is needed in order to avoid further anthropogenically induced climate change. The ocean provides a largely untapped source of renewable energy. As a result, harvesting electrical power from the wind and tides has sparked immense government and commercial interest but with relatively little detailed understanding of the p...

Uncertainties related to fatigue damage estimation of non-linear systems are highly dependent on the tail behaviour and extreme values of the stress range distribution. By using a combination of the First Order Reliability Method (FORM) and Monte Carlo simulations (MCS), the accuracy of the fatigue estimations may be improved for the same computational efforts. The method is applied to a bottom...

Wind turbines components are subject to considerable stresses and fatigue due to extreme environmental conditions to which they are exposed, especially those located offshore. With this aim, the present work explores two different approaches on fatigue damage estimation and remaining useful life predictions of wind turbine blades. The first approach uses the rainflow counting algorithm. The sec...

Nacelle based LIDAR (Light detection and ranging) systems provide preview information of wind disturbances at various distances in front of a wind turbine. Preliminary work towards this objective [1] has shown that the predictive knowledge of the rotor effective wind speed can be used to improve the speed regulation by a predictive feedforward update to the collective pitch feedback controller,...

The further integration of wind energy into electrical power systems poses operational challenges as the variability in wind power reduces transient stability. To guarantee a stable and secure power system operation, maximum allowable power ramps are defined in grid codes that transmission service operators (TSOs) specify. In this thesis it shall be investigated how a wind power system with ene...

Offshore wind energy is being developed on a very large scale in the European seas. The objective of developing wind energy offshore is to capture greater wind speeds than are encountered onshore and as a result more energy. With this also come more challenges in the design of wind turbines due to the hostile offshore environment. Currently the standards for offshore wind turbines prescribe a s...

The suitability of turbine configurations to different wind resources has been traditionally restricted to considering turbines operating as standalone entities. In this paper, a framework is thus developed to investigate turbine suitability in terms of the minimum cost of energy offered when operating as a group of optimally-micro-sited turbines. The four major steps include: (i) characterizin...

This paper focuses on generic Type 4 wind turbine generators models, their applicability in modern HVDC connections and their capability to provide advanced ancillary services therefrom. A point-to-point HVDC offshore connection is considered. Issues concerning coordinated HVDC and wind farm control as well as the need of a communication link are discussed. Two possible control configurations a...

Fossil Fuels are always considered as environmental pollutants. On the other hand, the political and economic situations highly affect the price of these fuels. Offshore wind and wave, as renewable energy sources, represent the better alternatives for electricity generation. Therefore, it is necessary that wind speeds effectively be estimated due to the absence of field measurements of the wind...