Status: this preprint was under review for the journal WES but the revision was not accepted.
Optimal Output Feedback H∞ Torque Control of a Wind Turbine Rotor using a Parametrically Scheduled Model
Dana Martin,Kathryn Johnson,Christopher Bay,Daniel Zalkind,Lucy Pao,Meghan Kaminski,and Eric Loth
Abstract. Wind turbines are nonlinear, time-varying systems that are subject and sensitive to model parameter variations and a stochastic wind field. For such applications, Linear Parameter Varying (LPV) control provides a state-space approach to designing nonlinear controllers with robust performance. LPV uses multi-input multi-output (MIMO) model with a guaranteed limit on the exogenous disturbance's gain with respect to performance signals. A robust matrix inequality synthesis of an H∞ based performance LPV controller using a parametrically varying model will be developed with the goal of obtaining a torque controller with drive-train damping properties. The technique guarantees a-priori performance values and closed-loop stability for the simplified model, and provides a systematic tuning procedure to adjust controller performance.
How to cite. Martin, D., Johnson, K., Bay, C., Zalkind, D., Pao, L., Kaminski, M., and Loth, E.: Optimal Output Feedback H∞ Torque Control of a Wind Turbine Rotor using a Parametrically Scheduled Model, Wind Energ. Sci. Discuss. [preprint], https://doi.org/10.5194/wes-2018-27, 2018.
The paper provides an account of the synthesis of a Linear Parameter Varying (LPV) controller and its improved performance as applied to a down-wind, two bladed, per-aligned rotor. The analysis of controller performance during a turbulent inflow with a mean wind speed of 4 m/s show increased performance in terms of better tip speed ratio tracking and reduced fatigue damage to various turbine components. The results provide a basis of LPV control and its ability to increase turbine lifetime.
The paper provides an account of the synthesis of a Linear Parameter Varying (LPV) controller...