Vestas

About: Vestas is a company organization based out in Aarhus, Denmark. It is known for research contribution in the topics: Turbine & Wind power. The organization has 1075 authors who have published 1519 publications receiving 23285 citations. The organization is also known as: Vestas Wind Systems & Vestas Wind Systems A/S.

Wind lidar evaluation at the Danish wind test site in Høvsøre

Abstract: Initial assessments of a wind lidar have shown the technology to have significant potential for wind field measurements in the wind energy industry. A more extended evaluation is now reported using a scanning lidar next to a meteorological mast with calibrated anemometers at the Riso wind test site in Hovsore on the windy northwest coast of Denmark. Results are presented of wind speed comparisons at heights up to 100 m above ground level showing excellent correlation between the lidar and the cup anemometers. Copyright © 2006 John Wiley & Sons, Ltd.

Method of controlling the operation of a wind turbine and wind turbine for use in said method

Abstract: The wind turbine (1) comprises a rotor (2) with a number of blades mounted for rotation about a mainly horizontal axis, and the pitch of the blades of the wind turbine is controlled in dependence on measured parameters in order to optimize the operation of the wind turbine with respect to produced energy under varying weather and wind conditions. By measuring mechanical loads on the blades (7, 8), and controlling the pitch of the blades of the wind turbine in such a way, that the measured mechanical loads are maintained below certain limits during operation, the control can be performed closer to the mechanical load limits of the blades without risk of exceeding these limits.

International comparison of requirements for connection of wind turbines to power systems

Abstract: Power production from wind turbines has increased considerably during the lost decade. Therefore today's wind turbines, which are typically set up in wind farms, have a significant influence on the ...

Methods of handling wind turbine blades and mounting said blades on a wind turbine, system and gripping unit for handling a wind turbine blade

Abstract: The invention relates to methods of handling wind turbine blades and mounting said blades on a wind turbine, said method comprising the steps of lifting a wind turbine hub to the nacelle of wind turbine with a lifting system and mounting the hub on the nacelle. Further, the method comprises the steps of gripping at least one wind turbine blade with a lifting system including at least one gripping unit for handling wind turbine blades, lifting said at least one wind turbine blade into close proximity to said hub, and mounting said at least one wind turbine blade on said hub. The invention also relates to a gripping unit for handling a wind turbine blade during transport.

Two methods for estimating aeroelastic damping of operational wind turbine modes from experiments

Abstract: The theory and results of two experimental methods for estimating the modal damping of a wind turbine during operation are presented. Estimations of the aeroelastic damping of the operational turbine modes (including the effects of the aerodynamic forces) give a quantitative view of the stability characteristics of the turbine. In the first method the estimation of modal damping is based on the assumption that a turbine mode can be excited by a harmonic force at its natural frequency, whereby the decaying response after the end of excitation gives an estimate of the damping. Simulations and experiments show that turbine vibrations related to the first two tower bending modes can be excited by blade pitch and generator torque variations. However, the excited turbine vibrations are not pure modal vibrations and the estimated damping is therefore not the actual modal damping. The second method is based on stochastic subspace identification, where a linear model of the turbine is estimated alone from measured response signals by assuming that the ambient excitation from turbulence is random in time and space. Although the assumption is not satisfied, this operational modal analysis method can handle the deterministic excitation, and the modal frequencies and damping of the first tower and first edgewise whirling modes are extracted. Copyright © 2006 John Wiley & Sons, Ltd.