On Singular Perturbations of Flexible and Variable-Speed Wind Turbines

Abstract EN

A model for the mechanical dynamics of a wind turbine is developed, which is the composition of three physical mechanisms: flexion, torsion, and rotational dynamics.

A first contribution is the identification of the essential physical parameters that provide a time-scale separation of these three mechanisms.

Under the assumption of singular perturbations the time-scale separation allows to work with a reduced model of order one.

This reduction has been essential for the control of this system allowing to control designers to take into account only the reduced-order model.

A second contribution consists in employing a measurement of the fore-aft nacelle acceleration with the reduced model, together with a Kalman filter to estimate the flexible DOFs of the system (tower and average blade deflection).

The successful approach is tested on high-order nonlinear aeroelastic simulator (FAST).