Wind turbine tower failure analysis and wind-induced vibration control

Abstract Wind turbine tower dynamic stress is related to the fatigue wear and reliability of the whole wind turbine structure. This paper deals with the problem of tower vibration control using a specially designed and built laboratory model. The considered wind turbine tower-nacelle model consists of a vertically arranged stiff rod (representing the tower), and a system of steel plates (representing nacelle and turbine assemblies) fixed at its top. The horizontally aligned tuned vibration absorber (TVA) with magnetorheological (MR) damper is located also at the top of the rod (in nacelle system). Force excitation sources applied horizontally to the tower itself and to the nacelle were both considered. The MR damper real-time control algorithms, including ground hook control and its modification, sliding mode control, linear and nonlinear (cubic and square root) damping, and adaptive solutions are compared to the open-loop case with various constant MR damper input current values and system without MR TVA (i.e., MR TVA in “locked” state). Comprehensive experimental analyses and their results are presented.

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Nonlinear Optimal-Based Vibration Control of a Wind Turbine Tower Using Hybrid vs. Magnetorheological Tuned Vibration Absorber

Energies ◽

10.3390/en14165145 ◽

2021 ◽

Vol 14 (16) ◽

pp. 5145

Author(s):

Paweł Martynowicz

Keyword(s):

Vibration Control ◽

Wind Turbine ◽

Energy Demand ◽

Control Method ◽

Vibration Absorber ◽

Real Time Control ◽

Time Control ◽

Working Space ◽

Wind Turbine Tower ◽

Tuned Vibration Absorber

This paper presents an implementation of a nonlinear optimal-based wind turbine tower vibration control method. An NREL 5.0 MW tower-nacelle model equipped with a hybrid tuned vibration absorber (HTVA) is analysed against the model equipped with a magnetorheological TVA (MRTVA). For control purposes, a 3 kN active actuator in parallel with a passive TVA is used in the HTVA system, while an MR damper is built in the MRTVA instead of a viscous damper, as in a standard TVA. All actuator force constraints are embedded in the implemented nonlinear control techniques. By employing the Pontryagin maximum principle, the nonlinear optimal HTVA control proposition was derived along with its simplified revisions to avoid a high computational load during real-time control. The advantage of HTVA over MRTVA in vibration attenuation is evident within the first tower bending frequency neighbourhood, with HTVA also requiring less working space. Using the appropriate optimisation fields enabled an 8-fold reduction of HTVA energy demand along with a (further) 29% reduction of its working space while maintaining a significant advantage of HTVA over the passive TVA. The obtained results are encouraging for the assumed mass ratio and actuator force limitations, proving the effectiveness and validity of the proposed approaches.

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Vibration control of wind turbine tower-nacelle model with magnetorheological tuned vibration absorber

Journal of Vibration and Control ◽

10.1177/1077546315591445 ◽

2015 ◽

Vol 23 (20) ◽

pp. 3468-3489 ◽

Cited By ~ 10

Author(s):

Paweł Martynowicz

Keyword(s):

Vibration Control ◽

Wind Turbine ◽

Sliding Mode ◽

Mr Damper ◽

Numerical Analyses ◽

Comsol Multiphysics ◽

Laboratory Model ◽

Vibration Absorber ◽

Wind Turbine Tower ◽

Tuned Vibration Absorber

Wind turbine tower dynamic load is related to the fatigue and reliability of the structure. This paper deals with the problem of tower vibration control using specially designed and built numerical and laboratory model. The regarded wind turbine tower-nacelle model consists of vertically arranged stiff rod (representing the tower), and a stiff body fixed at its top representing nacelle assembly that is equipped with horizontally aligned tuned vibration absorber (TVA) with magnetorheological (MR) damper. To model tower-nacelle dynamics, Comsol Multiphysics finite element method environment was used. For time and frequency domain numerical analyses (including first and second bending modes of vibration) of system with TVA and MR damper models, MATLAB/Simulink environment was used with Comsol Multiphysics tower-nacelle model embedded. Force excitation sources applied horizontally to the nacelle, and to the tower itself were both considered. The MR damper real-time control algorithms, including ground hook control and its modification, sliding mode control, linear and nonlinear (cubic and square root) damping, and adaptive solutions are compared to the open-loop case with various constant MR damper input current values and system without MRTVA (i.e. MRTVA in ‘locked’ state). Comprehensive numerical analyses results are presented along with Vensys 82 full-scale tower-nacelle model validation. Finally, preliminary results of laboratory tests are included.

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