Control algorithms for rotor load mitigation are today generally adopted by industry. Most of them are based on the Coleman transformation, which is easy to implement and bears satisfactory results when the rotor is balanced. A multitude of causes, e.g., blade erosion, dirt, and especially pitch misalignment, may create significant imbalances. This gives birth to undesirable vibrations and reduced control performance in terms of load mitigation. In this paper, an alternative transformation is introduced, able to detect and quantify the rotor load harmonics due to aerodynamic imbalance. Next, a control algorithm, capable of targeting rotor imbalance itself and simultaneously lowering rotor loads, is presented. The effectiveness of the proposed solution is confirmed through simulations in virtual environment.

References

References
1.
Bossanyi
,
E.
,
2003
, “
Wind Turbine Control for Load Reduction
,”
Wind Energy
,
6
(
3
), pp.
229
244
.
2.
Bossanyi
,
E.
,
2003
, “
Individual Blade Pitch Control for Load Reduction
,”
Wind Energy
,
6
(
2
), pp.
119
128
.
3.
Bossanyi
,
E.
,
2004
, “
Developments in Individual Blade Pitch Control
,”
The Science of Making Torque From Wind Conference
, Delft, The Netherlands, Apr. 19–21, pp. 486–497.
4.
Bossanyi
,
E.
,
2005
, “
Further Load Reductions With Individual Pitch Control
,”
Wind Energy
,
8
(
4
), pp.
481
485
.
5.
Bottasso
,
C. L.
,
Croce
,
A.
,
Riboldi
,
C. E. D.
, and
Nam
,
Y.
,
2013
, “
Multi-Layer Control Architecture for the Reduction of Deterministic and Non-Deterministic Loads on Wind Turbines
,”
Renewable Energy
,
51
, pp.
159
169
.
6.
Bottasso
,
C. L.
,
Croce
,
A.
,
Riboldi
,
C. E. D.
, and
Salvetti
,
M.
,
2014
, “
Cyclic Pitch Control for the Reduction of Ultimate Loads on Wind Turbines
,”
J. Phys. Conf. Ser.
,
524
(
1
), p.
012063
.
7.
Geyler
,
M.
, and
Caselitz
,
P.
,
2007
, “
Individual Blade Pitch Control Design for Load Reduction on Large Wind Turbines
,”
European Wind Energy Conference
(
EWEC
), Milan, Italy, May 7–10, pp. 82–86.
8.
Leithead
,
W. E.
,
Neilson
,
V.
, and
Dominguez
,
S.
,
2009
, “
Alleviation of Unbalanced Rotor Loads by Single Blade Controllers
,”
European Wind Energy Conference
(
EWEC
), Marseille, France, Mar. 16–19, pp. 576–615.
9.
Kanev
,
S.
, and
Van Engelen
,
T. G.
,
2009
, “
Exploring the Limits in Individual Pitch Control
,”
European Wind Energy Conference
(
EWEC
), Marseille, France, Mar. 16–19, pp. 1–10.
10.
Riboldi
,
C. E. D.
,
2016
, “
On the Optimal Tuning of Individual Pitch Control for Horizontal Axis Wind Turbines
,”
Wind Eng.
,
40
(
4
), pp. 398–416.
11.
Riboldi
,
C. E. D.
,
2012
, “
Advanced Control Laws for Variable Speed Wind Turbines and Supporting Enabling Technologies
,”
Ph.D. thesis
, Politecnico di Milano, Milan, Italy.
12.
Cacciola
,
S.
,
Munduate Agud
,
I.
, and
Bottasso
,
C. L.
,
2016
, “
Detection of Rotor Imbalance, Including Root Cause, Severity and Location
,”
J. Phys.: Conf. Ser.
,
753
(7), p.
072003
.
13.
Petrović
,
V.
,
Jelavić
,
M.
, and
Baotić
,
M.
,
2014
, “
Advanced Control Algorithms for Reduction of Wind Turbine Structural Loads
,”
Renewable Energy
,
76
, pp.
418
431
.
14.
Bottasso
,
C. L.
,
Cacciola
,
S.
, and
Schreiber
,
J.
,
2015
, “
A Wake Detector for Wind Farm Control
,”
J. Phys.: Conf. Ser.
,
625
(
1
), p.
012007
.
15.
Jonkman
,
J. M.
, and
Buhl
,
M.
,
2005
, “
FAST User's Guide
,” National Renewable Energy Laboratory, Boulder, CO.
16.
IEC
,
2005
, “
Wind Turbines—Part 1: Design Requirements
,” International Electrotechnical Commission, Geneva, Switzerland, Standard No.
IEC61400-1
.
17.
Bottasso
,
C. L.
,
Croce
,
A.
,
Riboldi
,
C. E. D.
, and
Nam
,
Y.
,
2012
, “
Power Curve Tracking in the Presence of a Tip Speed Constraint
,”
Renewable Energy
,
40
(
1
), pp.
1
12
.
18.
Bottasso
,
C. L.
, and
Cacciola
,
S.
,
2014
, “
Model-Independent Periodic Stability Analysis of Wind Turbines
,”
Wind Energy
,
18
(
5
), pp.
865
887
.
19.
Riboldi
,
C. E. D.
, and
Cacciola
,
S.
,
2017
, “
Individual Pitch Control for Two-Bladed Wind Turbines Via Multi-Blade Multi-Lag Transformation
,”
Wind Energy
, accepted.
You do not currently have access to this content.