Research On Structural Strength Of Wind Turbine Pitch Bearing

Blade bearing is the core component of the blade control system of the windturbine which are mainly loaded with axial force, radial force and tilting moment, so it has complicated load conditions, poor environmental conditions and lower overall stiffness characteristics. Thus the intensity of the pitch bearing not only affect the use of the bearing, and even for the overall stability of wind turbines and has an important impact on efficient and safe operation of wind turbine generator. This paper takes a type of pitch bearing as the research object, derivation and established the balance equation of pitch bearing with rigid body and flexible body in complex load situations based on geometric parameters of the bearing, Hertz theory and basics of elasticity. The results of different theoretical models are got by using numerical methods to solvethe equilibrium equation. To save working time and improve the efficiency of finite element analysis, built a pitch bearing analysis module in finite element software-ANSYS by applied the secondary development of ANSYS. Finite element analysis in a certain type of pitch bearing, compared the finite element results with theory results in load distribution, deformation of bearing, and discussed the differences between the results and the reasons for the differences. Finally, according to the pitch bearing analysis module, further discussion the parameters of pitch bearing such as the number and size of rolling element, bolt hole diameter, the thickness of the ring and the influence of these parameters to the load distribution and the deformation of ring is also studied. Work done by this paper provides an important theoretical basis for the design of pitch bearing, and has theoretical significance and practical engineering value.