Blade pitch

About: Blade pitch is a research topic. Over the lifetime, 5321 publications have been published within this topic receiving 63134 citations.

Telescoping wind turbine blade

Abstract: A wind turbine blade made of a fixed blade section with an integral mounting flange for attachment to a wind turbine hub. A moveable blade section is attached to the fixed blade section and is free to move in a longitudinal direction relative to the fixed blade section. A positioning device controllably positions the moveable blade section to vary the overall length of the blade. This allows the wind turbine's rotor diameter to be adjusted. The rotor diameter can be increased in order to provide high power output in low wind conditions and it can be decreased in order to minimize loads in high wind conditions.

Analysis of measurements and simulations from the Hywind Demo floating wind turbine

Abstract: A comparative dynamic analysis between full-scale measurements from the floating wind turbine Hywind Demo and corresponding numerical simulations is presented. A description of the main characteristics of the Hywind Demo structure, control system and important measurements are given. A method for estimation of the incident wave elevation on Hywind Demo is outlined. Comparative dynamic simulations are carried out with the estimated wave elevation time series as input, together measured and further refined statistical parameters of the wind field. Roll, pitch and yaw motions, tower bending moments, mooring line tensions, power production, rotor speed and blade pitch angle are compared for one case below and one case above the rated wind speed. Overall, good agreement is seen between the measured and simulated responses, and it is believed that the considered analysis tool is well suited for confirming the design of a future optimized floating wind turbine based on the Hywind concept. Copyright © 2014 John Wiley & Sons, Ltd.

Controlling Platform Motions and Reducing Blade Loads for Floating Wind Turbines

Abstract: Offshore sites hold great promise for the growth of wind energy. To tap the vast resource in deep water sites, new support structures, such as those that float, are needed. For floating structures to succeed, they must withstand the offshore wind and wave environment. Two new methods for controlling a floating turbine and reducing the platform and blade loads are presented. The first is a method for controlling collective blade pitch and reducing platform pitch motion, a significant problem for floating structures. The rated generator speed is made a function of the platform pitch velocity. When the platform is pitching upwind, the set point generator speed is set to a larger value, and vice versa. For constant generator torque, this approach essentially makes the rated power a variable that depends on the platform pitch velocity. Fundamentally, this control approach trades power variability for platform pitch variability. The results will show substantial reductions in platform pitch motion but minor inc...