Dynamics of flexible tower-blade and rigid nacelle system: dynamic instability due to their interactions in wind turbine
نویسندگان
چکیده
The dynamic stability of a coupled tower-blade wind turbine system is investigated analytically and experimentally. Coupled equations of motion and associated boundary conditions for the wind tower and a rotating blade are derived by considering the lateral acceleration of the nacelle at the tip of the tower, which is the base of the flexible blade. The coupled eigenvalues are computed for various blade rotational speeds and densities of the tower material by using Galerkin’s method in spatial coordinates. The results indicate that the coupled tower-blade system becomes unstable when certain vibrational modes of the tower and blade coalesce. Additionally, the vibration of the rotating blades is measured using a wireless telemetry system attached to the small-scale tower-blade wind power system, and the results are compared with those of the analytical study. The experiment shows that instability is observed in the same ranges of the blade rotational speed as those predicted by our analytical study.
منابع مشابه
Control of flapwise vibrations in wind turbine blades using semiactive tuned mass dampers
The increased size and flexibility of modern multi-Megawatt wind turbines has resulted in the dynamic behaviour of these structures becoming an important design consideration. The aim of this paper is to study the variation in natural frequency of wind turbine blades due to centrifugal stiffening and the potential use of semi-active tuned mass dampers (STMDs) in reducing vibrations in the flapw...
متن کاملNonlinear Dynamics of Wind Turbine Wings
Preface The present thesis " Nonlinear Dynamics of Wind Turbine Wings " has been prepared in connection with a Ph.D. study carried out in the great interest in the project and persistent guidance throughout my study. During a 4 months stay at the DUWIND group, Delft University, the Netherlands, I was introduced to the fields of computational fluid dynamics with emphasis on fluid structure inter...
متن کاملMorphing Segmented Wind Turbine Concept
A morphing segmented concept is proposed herein for future extreme-scale wind turbine systems. The morphing may be accomplished by using segmented blades connected by screw sockets and a tension cable system. At low wind and rotor speeds, the segmented blades are fully tensioned and set at high pitch to ensure start-up and maximum power at low speeds. At high rotor rpm, the cable tension can be...
متن کاملDifferent Types of Pitch Angle Control Strategies Used in Wind Turbine System Applications
The most common controller in wind turbine is the blade pitch angle control in order to get the desired power. Controlling the pitch angle in wind turbines has a direct impact on the dynamic performance of the machine and fluctuations in the power systems. Due to constant changes in wind speed, the wind turbines are of nonlinear and multivariate system. The design of a controller that can ad...
متن کاملEvaluation of Turbulence on the Dynamics of Monopile Offshore Wind Turbine under the Wave and Wind Excitations
In recent years, the use of offshore wind turbines has been considered on the agenda of the countries which have a significant maritime boundary due to more speed and stability of wind at sea. The aim of this study is to investigate the effect of wind turbulence on the aero-hydrodynamic behavior of offshore wind turbines with a monopile platform. Since in the sea, the wind turbine structures ar...
متن کامل