Periodic Load Estimation of a Wind Turbine Tower using a Model Demodulation Transformation

The ever-increasing power capacities of wind turbines promote the use of tall and slender turbine towers. This poses a challenge from a fatigue loading perspective by the relocation of the first and lightly-damped tower side-side natural frequency into the turbine operating regime, promoting its excitation during nominal operation. The...

The Proportional Integral Notch and Coleman Blade Effective Wind Speed Estimators and Their Similarities

The estimation of the rotor effective wind speed is used in modern wind turbines to provide advanced power and load control capabilities. However, with the ever increasing rotor sizes, the wind field over the rotor surface shows a higher degree of spatial variation. A single effective wind speed estimation therefore limits the attainable...

The Immersion and Invariance Wind Speed Estimator Revisited and New Results

The Immersion and Invariance (II) wind speed estimator is a powerful and widely-used technique to estimate the rotor effective wind speed on horizontal axis wind turbines. Anyway, its global convergence proof is rather cumbersome, which hinders the extension of the method and proof to time-delayed and/or uncertain systems. In this letter, we...