Fatigue Life Prediction of Five MW Wind Turbine Blade Based on Long-Term Wind Speed Simulation

This paper studies the load spectrum and fatigue life estimation method of large wind turbine blades. A method based on the wind speed spectrum and stress response at each wind speed is proposed to calculate the response spectrum of the dangerous part of the blade. The response of the blade at each wind speed is obtained by finite element analysis. Considering the limited wind speed data, it is not enough to cover the whole situation of blade life experience, which will bring great discreteness to the blade fatigue life estimation method proposed in this paper. In this paper, the Markov chain Monte Carlo method is used to predict enough wind speed data to reduce the discreteness of life estimation. Because the traditional linear fatigue damage accumulation theory fails to consider the impact of loads below the fatigue limit on fatigue damage, this paper uses a fatigue damage theory based on fuzzy theory, introduces appropriate membership functions, and fully considers the impact of loads below the fatigue limit on fatigue damage. The calculation results are more in line with the actual situation.