STUDY ON MODAL PARAMETER IDENTIFICATION OF WIND TURBINES BASED ON STEADY-STATE HARMONIC EXCITATIONS

This paper proposes a method of modal parameter identification for wind turbines based on steady-state harmonic excitations，considering the coupling of fore-aft and side-side aerodynamic damping. In this study，a finite element model was established considering the inertial exciter element. The influences of the exciter mass，exciting frequency range and interval，exciting force amplitude and turbulent wind on the identification results were analyzed. The effective stroke of the inertia exciter was analyzed by selecting different excitation frequencies and the weight of the movable mass. The identified parameters by the steady-state harmonic excitation method in this paper were compared with the identified results obtained by the stochastic subspace identification method and free decay identification method through the fully coupled OpenFAST numerical simulations. The results show that the steady-state harmonic excitation method is completely feasible to identify the modal parameters of wind turbines no matter they are parked or operating，and the identification results are more reliable. © 2024 Science Press. All rights reserved.