Nonlinear dynamic analysis of wind turbine gear systems under uncertainty

Abstract

Wind turbine drivetrains exhibit a high sensitivity to parameter variations, which significantly affects their dynamic behaviour and operational reliability. This paper presents a nonlinear dynamic robustness analysis of a wind turbine gearing system subjected to coupled parameter uncertainties and nonlinear excitation. The study investigates the system responses under uncertainties affecting key parameters, including torsional stiffness, wind speed, bending stiffness, and traction–compression stiffness. The nonlinear dynamic model is solved using a fifth-order Runge–Kutta numerical integration scheme to accurately capture the system behaviour. To efficiently quantify uncertainty propagation, the generalized polynomial chaos method is employed and systematically compared with Monte Carlo simulations. Attention is devoted to the influence of extreme parameter variations and coupled uncertainty effects, highlighting their critical role in amplifying the dynamic responses of the drivetrain system. The obtained results provide valuable insights into the robustness and dynamic reliability of wind turbine gearing systems operating under nonlinear and uncertain conditions.