A new finite element approach for the analysis of slewing bearings in wind turbine generators using superelement techniques

Several analytical models have been proposed to estimate the load distribution and the deformation of slewing bearing assemblies in wind turbine generators (WTGs). Even though they are a useful tool for designers as a first approach, most of them assume rigid rings and rigid supporting structures, leading to inaccurate results; even if compliance is considered in some models, only certain boundary conditions can be taken into account, and their complex and diverse nature make often these models inaccurate. For this reason, WTG manufacturers need costly FE analyses to obtain results adapted to the particular geometries and operational conditions of their yaw and pitch bearings assemblies. In this sense, this work presents a superelement-based FE model that significantly reduces the computational cost with a negligible accuracy loss.