Year-end Sale % OFF 
Abstract
Modern multi-megawatt wind turbines are currently designed as pitch-regulated machines, i.e., machines that use the rotation of the blades (pitching) in order to adjust the aerodynamic torque, such that the power is maintained constantly throughout a wide range of wind speeds when they exceed the design value (rated wind speed). Thus, pitch control is essential for optimal performance. However, the pitching activity is not for free. It introduces vibrations to the tower and blades and generates fatigue loads. Hence, pitch control requires a compromise between wind turbine performance and safety. In the past two decades, many approaches have been proposed to achieve different objectives and to overcome the problems of a wind energy converter using pitch control. The present work summarizes control strategies for problem of wind turbines, which are solved by using different approaches of pitch control. The emphasis is placed on the bibliographic information, but the merits and demerits of the approaches are also included in the presentation of the topics. Finally, very large wind turbines have to simultaneously satisfy several control objectives. Thus, approaches like collective and individual pitch control, tower and blade damping control, and pitch actuator control must coexist in an integrated control system.
Highlights
Large wind turbines are almost exclusively implemented by three-bladed horizontalaxis machines with variable speed and variable pitch
A linear quadratic regulator (LQR) [119], a linear quadratic Gaussian (LQG) control [116,120], and a robust control system design [77,104] are reported in the literature
The results show an important improvement in the load reduction
Summary
Large wind turbines are almost exclusively implemented by three-bladed horizontalaxis machines with variable speed and variable pitch. In Region III, the wind turbine works with overrated wind speed, i.e., the value for which the machine was designed for normal operation. The immediate consequence is that the control action must be fast, which implies a sharp breaking when the set point is reached This leads, on the one hand, to the occurrence of important loads and, on the other hand, introduces rapid disturbances in the thrust force, which results in vibrations in the blades and tower. The control problem in the full load region is undertaken by pitch control, which in turn has to consider simultaneously regulation of rotational speed and power, rapid response in front of turbulence, damping of vibrations, and reduction of loads.
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
