Actuator Saturation Control of Floating Wind Turbines

A state feedback aerodynamic controller is proposed for the stabilization and reduction of platform/tower pitch vibrations of a spar-type floating wind turbine, considering blade pitch saturation effects. The controller is synthesized from a linearized rigid body model developed for a NREL 5-MW offshore wind turbine operating at the above rated condition (region 3). Wind turbulence and wave induced loads are obtained from the blade element momentum (BEM) aerodynamic theory and Morison’s equation, respectively. The simulation results show that the proposed nonlinear control system yields significant vibration reduction in comparison to a proportional-integral controller.Copyright © 2012 by ASME