On the Design of Measurement Campaigns for Fatigue Life Monitoring of Offshore Wind Turbines

On-site fatigue monitoring of offshore wind turbines using mechanical strain measurements adds maintenance effort. Instead, estimating loads is more cost effective. Load estimation can be done with data driven models requiring only a short period of mechanical strain measurements. This paper elaborates on the amount and type of sample data needed to establish a reliable fatigue estimator for the entire operational life of the turbine. It is shown that the diversity of loading situations needs to be reflected within the model and a systematic approach for sample data selection and categorization is suggested. The study reveals direct implications for load measurement campaigns conducted for this purpose.