Reliability Analysis of Fatigue Fracture of Wind Turbine Drivetrain Components

One of the main challenges for the wind turbine industry currently, is to reduce the cost of levelized energy, especially for offshore wind. Failures in the wind turbine drivetrain generally result in the second largest down times of the wind turbine, hence significantly increasing the cost of operation and maintenance. The manufacturing of casted drivetrain components, like the main shaft of the wind turbine, commonly result in many smaller defects through the volume of the component with sizes that depend on the manufacturing method. This paper considers the effect of the initial defect present in the volume of the casted ductile iron main shaft, on the reliability of the component. The probabilistic reliability analysis conducted is based on fracture mechanics models. Additionally, the utilization of the probabilistic reliability for operation and maintenance planning and quality control is discussed.