Fatigue analysis of wind turbine gearbox bearings using SCADA data and miner's rule

This paper presents studies of wind turbine load estimation, based upon SCADA data, to derive bearing load histograms for the high speed shaft (HSS) of a typical, three-stage, wind turbine gearbox. Rain-flow counting has been applied to determine the number of loading occurrences at different load values. Damage ratios for bearings have been predicted using this data by the application of Miner's rule. Results show that the bearings have an overload Cycle Ratio of less than 20% above rated and overloads of Load Ratio of 1.0~1.1 incurring significant damage to the bearings.