Polynomial stability of wind turbine tower models

Abstract

We investigate the stabilization of mathematical models describing the structural dynamics of monopile wind turbine towers. In the fore-aft plane, we show that the system becomes polynomially stable with an energy decay rate of $t^{-1}$ under static output feedback that relies on the velocity and/or angular velocity of the nacelle. Additionally, we prove that a tuned mass damper (TMD) in the nacelle ensures polynomial stability with the same energy decay rate, offering a viable alternative to active control. For the side-to-side plane, we analyze a model incorporating a hydraulic power transmission system and prove that feedback from the nacelle's angular velocity and the generator load torque leads to polynomial stability of the system.