Analysis of two modeling approaches for fatigue estimation and remaining useful life predictions of wind turbine blades

Wind turbines components are subject to considerable stresses and fatigue due to extreme environmental conditions to which they are exposed, especially those located offshore. With this aim, the present work explores two different approaches on fatigue damage estimation and remaining useful life predictions of wind turbine blades. The first approach uses the rainflow counting algorithm. The second approach comes from a fatigue damage model that describes the propagation of damage at a microscopic scale due to matrix cracks which manifests in a macroscopic scale as stiffness loss. Both techniques have been tested using the information provided by the blade root moment sensor signal obtained from the well known wind turbine simulator FAST (Fatigue, Aerodynamics, Structures and Turbulence).