Smooth Transition Between Controllers for Floating Wind Turbines

Abstract This paper presents a novel wind turbine control system which gives a smooth power output during transitions between different controllers. The paper presents an implementation of a control system designed for an offshore floating wind turbine using a linear Model Predictive Control approach.The performance is investigated in computer simulations, with emphasis on stability in the tower fore–aft motion and behaviour during transition between controllers. The results clearly demonstrate that the wind turbine using the proposed algorithm for smooth transition indeed exhibits a smooth system behaviour. In comparison to a case with sudden transition, the behaviour is found to be significantly improved. Moreover, tower oscillations are found to be stable, by virtue of the controller prediction horizon exceeding the natural periodicity of the tower oscillations.Smooth system behaviour is important to increase the lifetime of critical parts of the turbine. With increasing turbine sizes such considerations are of increasing importance, making the results obtained in this paper of particular relevance for large wind turbines, both onshore and offshore.

[1]  Matthew A. Lackner,et al.  Controlling Platform Motions and Reducing Blade Loads for Floating Wind Turbines , 2009 .

[2]  Thor I. Fossen,et al.  Handbook of Marine Craft Hydrodynamics and Motion Control: Fossen/Handbook of Marine Craft Hydrodynamics and Motion Control , 2011 .

[3]  Jan M. Maciejowski,et al.  Predictive control : with constraints , 2002 .

[4]  Thomas Bak,et al.  Optimal control of a ballast-stabilized floating wind turbine , 2011, 2011 IEEE International Symposium on Computer-Aided Control System Design (CACSD).

[5]  M. Chinchilla,et al.  Control of permanent-magnet generators applied to variable-speed wind-energy systems connected to the grid , 2006, IEEE Transactions on Energy Conversion.

[6]  Andrew Kusiak,et al.  Dynamic control of wind turbines , 2010 .

[7]  Nikola Hure.  Model Predictive Control of a Wind Turbine , 2012 .

[8]  T. Funabashi,et al.  Robust Predictive Control of Variable-Speed Wind Turbine Generator by Self-Tuning Regulator , 2007, 2007 IEEE Power Engineering Society General Meeting.

[9]  Andrey V. Savkin,et al.  A model predictive control approach to the problem of wind power smoothing with controlled battery storage , 2010 .

[10]  Eivind Lindeberg,et al.  Optimal Control of Floating Offshore Wind Turbines , 2009 .

[11]  Torben J. Larsen,et al.  A method to avoid negative damped low frequent tower vibrations for a floating, pitch controlled wind turbine , 2007 .

[12]  Karl Stol,et al.  Performance analysis of individual blade pitch control of offshore wind turbines on two floating platforms , 2011 .

[13]  B. Dakyo,et al.  Large Band Simulation of the Wind Speed for Real-Time Wind Turbine Simulators , 2002, IEEE Power Engineering Review.

[14]  J. Jonkman.  Influence of Control on the Pitch Damping of a Floating Wind Turbine , 2008 .

[15]  Karl Stol,et al.  Individual blade pitch control of floating offshore wind turbines , 2010 .

[16]  Michael Nikolaou,et al.  Model predictive controllers: A critical synthesis of theory and industrial needs , 2001 .

[17]  Ted K.A. Brekken,et al.  On Model Predictive Control for a point absorber Wave Energy Converter , 2011, 2011 IEEE Trondheim PowerTech.

[18]  Torgeir Moan,et al.  Ameliorating the Negative Damping in the Dynamic Responses of a Tension Leg Spar-Type Support Structure with a Downwind Turbine , 2011 .