Extreme gusts and their role in wind turbine design

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...

Assessing the Severity of Wind Gusts with Lidar

Lidars have gained a lot of popularity in the field of wind energy, partly because of their potential to be used for wind turbine control. By scanning the oncoming wind field, any threats such as gusts can be detected early and high loads can be avoided by taking preventive actions. Unfortunately, lidars suffer from some inherent weaknesses that...

Importance sampling of severe wind gusts

An important problem that arises during the design of wind turbines is estimating extreme loads with sufficient accuracy. This is especially difficult during iterative design phases when computational resources are scarce. Over the years, many methods have been proposed to extrapolate extreme load distributions from relatively short time series...

Connection of large-scale wind power generation to the Dutch electrical power system and its impact on dynamic behaviour

Installed wind power world wide is increasing rapidly. The increase in wind power in the European electricity grid is expected to have its impact on the system behaviour. A European study, European Wind Integration Study (EWIS), was thus set up to study the impact of wind power. This thesis was carried out in parallel with EWIS and overlaps at...

De regeling van het Mach getal in de hoge snelheids tunnel van het NLR

The High Speed wind Tunnel (HST) of the National Aerospace Laboratory NLR is one of the major transonic windtunnels and is used for aerodynamic research on scale models. The measurements require the control of the Mach number. Two kinds of controller tasks can be distinguished: keeping the Mach number constant, and realizing a different Mach...