Assessment of wind turbine drive-train fatigue loads under torsional excitation. (15th November 2015)

• Record Type: Journal Article
• Authors: Gallego-Calderon, Juan; Natarajan, Anand
• Is Part Of: Engineering structures. Volume 103(2015:Nov. 15)
• Page Start: 189
• Page End: 202
• Publication Date: 2015-11-15
• Subjects: Gearbox -- Drive-train -- Electro-mechanical models -- Wind energy -- Wind turbine -- Fatigue life; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2015.09.008
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Identification of the modes that drive the fatigue in a planetary stage gearbox. Effects of the turbine dynamics in the planetary bearings fatigue loads. A fast electromechanical drivetrain model coupled to an aeroelastic tool. Abstract: This paper establishes validated models that can accurately account for the dynamics of the gearbox, along with the external dynamics that excite the system. A drive-train model implementation is presented where the gearbox and generator are coupled to the wind turbine structure in a dynamic simulation environment. The wind turbine is modelled using HAWC2 (Horizontal Axis Wind turbine simulation Code 2nd generation) and the gearbox is described using lumped parameters in MATLAB/Simulink. Each component in the gearbox model includes rotational and translational degree-of-freedom (DOF), which allows the computation of the bearing and gear-mesh loads. The proposed models are validated by experiments from a 750 kW test-rig. The drive-train model is configured for a 5 MW power capacity and coupled to the corresponding wind turbine and load simulations are carried out under turbulent wind following the guidelines from the IEC 61400-1 standard. Fatigue analysis shows the effect in the bearing damage equivalent loads, when including a detailed drive-train model in the overall wind turbine simulation for a 20 year period. Results show a higher level of damage (up to 180%) when the detailed model is used in comparison to a simplified approach for load calculation. It is found that some of the wind turbine modes can have negative consequences on the life-time of the planetary bearings.