Aerodynamic damping and bend–twist coupling significantly affect the dynamic response of wind turbines. In this paper, unsteady aerodynamics, aerodynamic damping, and bend–twist coupling (twist-towards-feather) are combined to establish a smart rotor model with trailing edge flaps (TEFs) based on a National Renewable Energy Laboratory (NREL) 5 MW reference horizontal-axis wind turbine. The overall idea is to quantitatively evaluate the influence of aerodynamic damping and bend–twist coupling on the smart rotor and to present the control effect of the TEFs under normal wind turbine operating conditions. An aerodynamic model considering the dynamic stall and aerodynamic damping as well as a structural bend–twist coupling model with the influence of gravity and centrifugal force are incorporated into the coupling analysis. The model verification shows that the present model is relatively stable under highly unsteady wind conditions. Then, a robust adaptive tracking (RAT) controller is designed to suppress fluctuations in both the flapwise tip deflection and output power. The simulations show an average reduction of up to 63.86% in the flapwise tip deflection power spectral density (PSD) of blade 1 at the 1P frequency, with an average reduction in the standard deviation of the output power of up to 34.33%.

References

References
1.
Lackner
,
M. A.
, and
Kuik
,
G. V.
,
2010
, “
A Comparison of Smart Rotor Control Approaches Using Trailing Edge Flaps and Individual Pitch Control
,”
Wind Energy
,
13
(
2–3
), pp.
117
134
.
2.
Berg
,
J. C.
,
Resor
,
B. R.
, and
Paquette
,
J. A.
,
2014
, “
Smart Wind Turbine Rotor: Design and Field Test
,” Sand.
3.
Barlas
,
T. K.
, and
Kuik
,
G. A. M. V.
,
2010
, “
Review of State of the art in Smart Rotor Control Research for Wind Turbines
,”
Prog. Aerosp. Sci.
,
46
(
1
), pp.
1
27
.
4.
Liu
,
X.
,
Lu
,
C.
, and
Liang
,
S.
,
2016
, “
Vibration-Induced Aerodynamic Loads on Large Horizontal Axis Wind Turbine Blades
,”
Appl. Energy
,
185
, pp.
1109
1119
.
5.
Chen
,
Z. J.
,
Stol
,
K. A.
, and
Mace
,
B. R.
,
2017
, “
Wind Turbine Blade Optimisation With Individual Pitch and Trailing Edge Flap Control
,”
Renew. Energy
,
103
, pp.
750
765
.
6.
Li
,
N.
,
Balas
,
M. J.
, and
Yang
,
H.
,
2016
, “
Numerical Investigation on the Selection of the System Outputs for Feedback Vibration Control of a Smart Blade Section
,”
ASME J. Vib. Acoust.
,
138
(
3
), p.
031013
.
7.
Zhang
,
M.
,
Yu
,
W.
, and
Xu
,
J.
,
2014
, “
Aerodynamic Physics of Smart Load Control for Wind Turbine due to Extreme Wind Shear
,”
Renew. Energy
,
70
(
5
), pp.
204
210
.
8.
Wilson
,
D. G.
,
Resor
,
B. R.
, and
Berg
,
D. E.
,
2010
, “
Active Aerodynamic Blade Distributed Flap Control Design Procedure for Load Reduction on the UpWind 5MW Wind Turbine
,”
48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition
,
Orlando, FL
,
Jan. 4–7
.
9.
Sun
,
X.
,
Dai
,
Q.
, and
Menon
,
M.
,
2017
, “
Design and Simulation of Active External Trailing-Edge Flaps for Wind Turbine Blades on Load Reduction
,”
J. Aerosp. Eng.
,
30
(
5
).
10.
Shirzadeh
,
R.
,
Devriendt
,
C.
, and
Bidakhvidi
,
M. A.
,
2013
, “
Experimental and Computational Damping Estimation of an Offshore Wind Turbine on a Monopile Foundation
,”
J. Wind Eng. Ind. Aerod.
,
120
(
120
), pp.
96
106
.
11.
Rezaei
,
R.
,
Fromme
,
P.
, and
Duffour
,
P.
,
2017
, “
Fatigue Life Sensitivity of Monopile-Supported Offshore Wind Turbines to Damping
,”
Renew. Energy
,
123
, pp.
450
459
.
12.
Devriendt
,
C.
,
Jordaens
,
P. J.
, and
Sitter
,
G. D.
,
2013
, “
Damping Estimation of an Offshore Wind Turbine on a Monopile Foundation
,”
Renew. Power Gen.
,
7
(
4
), pp.
401
412
.
13.
Valamanesh
,
V.
, and
Myers
,
A. T.
,
2014
, “
Aerodynamic Damping and Seismic Response of Horizontal Axis Wind Turbine Towers
,”
J. Struct. Eng.
,
140
(
11
), p.
04014090
.
14.
Hansen
,
M. H.
,
2004
, “
Aeroelastic Stability Analysis of Wind Turbines Using an Eigenvalue Approach
,”
Wind Energy
,
7
(
2
), pp.
133
143
.
15.
Chen
,
B.
,
Zhang
,
Z.
, and
Hua
,
X.
,
2017
, “
Identification of Aerodynamic Damping in Wind Turbines Using Time-Frequency Analysis
,”
Mech. Syst. Signal Process.
,
91
, pp.
198
214
.
16.
Murtagh
,
P. J.
, and
Basu
,
B.
,
2007
, “
Identification of Equivalent Modal Damping for a Wind Turbine at Standstill Using Fourier and Wavelet Analysis
,”
Proc. Inst. Mech. Eng., Part K
,
221
(
4
), pp.
577
589
.
17.
Liu
,
X.
,
Lu
,
C.
, and
Li
,
G.
,
2017
, “
Effects of Aerodynamic Damping on the Tower Load of Offshore Horizontal Axis Wind Turbines
,”
Appl. Energy
,
204
, pp.
1101
1114
.
18.
Hafeez
,
M. M. A.
, and
El-Badawy
,
A. A.
,
2018
, “
Flutter Limit Investigation for a Horizontal Axis Wind Turbine Blade
,”
ASME J. Vib. Acoust.
,
140
(
4
), p.
041014
.
19.
Ju
,
D.
, and
Sun
,
Q.
,
2017
, “
Modeling of a Wind Turbine Rotor Blade System
,”
ASME J. Vib. Acoust.
,
139
(
5
), p.
051013
.
20.
Kwon
,
S.
,
Chung
,
J.
, and
Hong
,
H. Y.
,
2013
, “
Structural Dynamic Modeling and Stability of a Rotating Blade Under Gravitational Force
,”
J. Sound Vib.
,
332
(
11
), pp.
2688
2700
.
21.
Bernhammer
,
L. O.
,
Navalkar
,
S. T.
, and
Sodja
,
J.
,
2017
, “
Experimental and Numerical Investigation of an Autonomous Flap for Load Alleviation
,”
J. Aircr.
,
54
(
2
), pp.
464
475
.
22.
Macquart
,
T.
,
Maheri
,
A.
, and
Busawon
,
K.
,
2017
, “
A Decoupling Control Strategy for Wind Turbine Blades Equipped with Active Flow Controllers
,”
Wind Energy
,
20
(
4
), pp.
569
584
.
23.
McWilliam
,
M. K.
,
Barlas
,
T. K.
, and
Madsen
,
H. A.
,
2017
, “
Aero-elastic Wind Turbine Design With Active Flaps for AEP Maximization
,”
Wind Energy. Sci. Discuss.
3
,
231
241
.
24.
Stäblein
,
A. R.
,
Hansen
,
M. H.
, and
Pirrung
,
G.
,
2017
, “
Fundamental Aeroelastic Properties of a Bend-Twist Coupled Blade Section
,”
J. Fluids Struct.
,
68
, pp.
72
89
.
25.
Brillante
,
C.
,
Morandini
,
M.
, and
Mantegazza
,
P.
,
2016
, “
Periodic Controllers for Vibration Reduction Using Actively Twisted Blades
,”
Aeronaut. J.
,
120
(
1233
), pp.
1763
1784
.
26.
Gueydon
,
S.
,
2016
, “
Aerodynamic Damping on a Semisubmersible Floating Foundation for Wind Turbines
,”
Energy Procedia
,
94
, pp.
367
378
.
27.
Rasmussen
,
F.
,
Petersen
,
J.
, and
Madsen
,
H.
,
1999
, “
Dynamic Stall and Aerodynamic Damping
,”
ASME J. Solar Energy Eng.
,
121
(
3
), pp.
150
155
.
28.
Choudhry
,
A.
,
Arjomandi
,
M.
, and
Kelso
,
R.
,
2016
, “
Methods to Control Dynamic Stall for Wind Turbine Applications
,”
Renew. Energy
,
86
, pp.
26
37
.
29.
Brian
,
R.
,
David
,
W.
, and
Dale
,
B.
,
2010
, “
Impact of Higher Fidelity Models on Simulation of Active Aerodynamic Load Control for Fatigue Damage Reduction
,”
48th AIAA Aerospace Sciences Meeting Including the New Horizons Forum and Aerospace Exposition
,
Orlando, FL
,
Jan. 4–7
.
30.
Andersen
,
P. B.
,
Gaunaa
,
M.
, and
Bak
,
C.
,
2005
, “
Load Alleviation on Wind Turbine Blades Using Variable Airfoil Geometry
,” ,
15
(
2
), pp.
121
134
.
31.
Gillebaart
,
T.
,
Bernhammer
,
L. O.
, and
Zuijlen
,
A. H. V.
,
2014
, “
Active Flap Control on an Aeroelastic Wind Turbine Airfoil in Gust Conditions Using Both a CFD and an Engineering Model
,”
5th Sci. Making Torque Wind Conf.
,
524
(
1
), p.
012060
.
32.
Andersen
,
P. B.
,
Henriksen
,
L.
, and
Gaunaa
,
M.
,
2010
, “
Deformable Trailing Edge Flaps for Modern Megawatt Wind Turbine Controllers Using Strain Gauge Sensors
,”
Wind Energy
,
13
(
2–3
), pp.
193
206
.
33.
Bergami
,
L.
, and
Poulsen
,
N. K.
,
2015
, “
A Smart Rotor Configuration with Linear Quadratic Control of Adaptive Trailing Edge Flaps for Active Load Alleviation
,”
Wind Energy
,
18
(
4
), pp.
625
641
.
34.
Bing
,
F. N.
,
Hesse
,
H.
, and
Kerrigan
,
E. C.
,
2014
, “
Efficient Aeroservoelastic Modeling and Control Using Trailing-Edge Flaps of Wind Turbines
,”
IEEE UKACC International Conference on Control.
,
Loughborough, UK
,
July 9–11
.
35.
Barlas
,
T. K.
,
Veen
,
G. J. V. D.
, and
Kuik
,
G. A. M. V.
,
2012
, “
Model Predictive Control for Wind Turbines With Distributed Active Flaps: Incorporating Inflow Signals and Actuator Constraints
,”
Wind Energy
,
15
(
5
), pp.
757
771
.
36.
Smit
,
J.
,
Bernhammer
,
L. O.
, and
Navalkar
,
S. T.
,
2016
, “
Sizing and Control of Trailing Edge Flaps on a Smart Rotor for Maximum Power Generation in low Fatigue Wind Regimes
,”
Wind Energy
,
19
(
4
), pp.
607
624
.
37.
Jonkman
,
J.
,
Butterfield
,
S.
, and
Musial
,
W.
,
2009
,
Definition of a 5-MW Reference Wind Turbine for Offshore System Development
,
National Renewable Energy Laboratory (NREL)
,
Golden, CO
.
38.
Zhang
,
W.
,
Bai
,
X.
, and
Wang
,
Y.
,
2018
, “
Optimization of Sizing Parameters and Multi-Objective Control of Trailing Edge Flaps on a Smart Rotor
,”
Renew. Energy
,
129
, pp.
75
91
.
39.
Fluent Inc
,
2012
, “
ANSYS FLUENT in ANSYS Workbench User’s Guide
,”
Canonsburg, PA
.
40.
Hansen
,
C.
,
2014
, “
AirfoilPrep: an Excel Workbook for Generating Airfoil Tables for AeroDyn and WT_Perf
,” NWTC Computer-Aided Engineering Tools.
41.
International Electrotechnical Commission
,
2005
, “
IEC 61400-1: Wind Turbines Part 1: Design Requirements
,”
International Electrotechnical Commission
.
42.
Bergami
,
L.
, and
Gaunaa
,
M.
,
2014
, “
Analysis of Aeroelastic Loads and Their Contributions to Fatigue Damage
,”
J. Phys.
,
555
(
1
), p.
012007
.
43.
Jonkman
,
B. J.
,
2015
, “
TurbSim User’s Guide (v1. 06.00)
,”
National Renewable Energy Laboratory
,
September-2012
,
NWTC Information Portal (TurbSim)
.
44.
Singh
,
M.
,
Muljadi
,
E.
, and
Jonkman
,
J.
,
2014
,
Simulation for Wind Turbine Generators–with FAST and MATLAB-Simulink Modules
,
National Renewable Energy Laboratory (NREL)
,
Golden, CO
.
45.
Wu
,
B.
,
Lang
,
Y.
, and
Zargari
,
N.
,
2011
,
Power Conversion and Control of Wind Energy Systems
,
John Wiley & Sons
,
New York
.
46.
Mahmuddin
,
F.
,
2017
, “
Rotor Blade Performance Analysis with Blade Element Momentum Theory
,”
Energy Procedia
,
105
, pp.
1123
1129
.
47.
Fung
,
Y. C.
,
2008
,
An Introduction to the Theory of Aeroelasticity
,
Courier Dover Publications
,
Mineola, New York
.
48.
Zhang
,
X.
, and
Lin
,
Y.
,
2016
, “
Robust Adaptive Tracking of Uncertain Nonlinear Systems by Output Feedback
,”
Int. J. Robust Nonlin. Control
,
26
(
10
), pp.
2187
2200
.
49.
Laks
,
J. H.
,
Pao
,
L. Y.
, and
Wright
,
A.D.
,
2009
, “
Control of Wind Turbines: Past, Present, and Future
,”
2009 American Control Conference
,
St. Louis, MO, USA
,
June 10–12
.
50.
Ogata
,
K.
,
2001
,
Modern Control Engineering (4th Edition), Dynamic Modelling and Simulation of Squirrel-Cage Asynchronous Machine with Non-Linear Effects
,
Revista Ciências Exatas
,
Prentice Hall, NJ
.
51.
Jonkman
,
J. M.
, and
Buhl
,
M.
,
2005
, “
FAST User’s Guide
,” Report no. NREL/EL-500-38230,
National Renewable Energy Laboratory
,
Golden, CO
.
You do not currently have access to this content.