Finite Element Analysis Of Blade Bearing Of MW-Class Wind Turbine

Blade bearing is the core component of the blade control system of the windturbine, and its use of performance, security and reliability determine the normaloperation and power generation efficiency of the wind turbine largely. So it becomesan important research direction of the wind turbine to improve the reliability and lifeof the blade bearing. The characteristics of blade bearing are its larger size, complexitystructure and force, and the difficulty of its design and production is relatively large.Blade bearing endures axial load, radial load and overturning moment mostly, andlow-speed rotation to achieve the purpose of the pitch in course. Its design standard isto ensure the static load carrying capacity, so the static load carrying capacity to meetthe requirements in the application is considered.In this study, according to the structure, dimensions and structural parameters of amodel double four points contact blade bearing of the1.5MW wind turbine windturbine pitch bearing for the benchmark, the wind turbine Pitch Bearing parametricmodeling interface is developed the use of ANSYS finite element analysis softwareand APDL parametric design language, the bearing simplified finite element model isbuilt quickly, the model is meshed, the reasonable boundary conditions is set, and it isloaded and solved, then we change the parameters of the bearing, and analyze theeffect of the parameters on the load distribution of the rolling and the contact stress ofthe law of the rolling element; The simplified model of the bolt connected isestablished and analyze the relationship between the bolt stress and bolt preload; theguidance is provided for the optimization design of the bearing and Improving thesafety and reliability of bolted by using the results, Which Has some theoreticalsignificance and practical value.As blade bearings is under the action of the limit load, in order to improve thecarrying capacity of the bearing, usually bearing has relatively large contact angle andsmall radius coefficient of groove curvature, and the clearance is in the zero-clearance and tend to negative clearance near the side of the appropriate value. The analysisresults show that as the contact angle increasing, the maximum contact stress firstlybecomes smaller and afterwards becomes bigger; as the groove radius of curvaturecoefficient increasing, the maximum contact stress constantly becomes smaller; as theclearance decreasing, the maximum contact stress firstly becomes smaller andafterwards becomes bigger; as the preload increasing, the maximum tensile stress ofbolt connection becomes bigger. In order to improve the security, reliability fatiguestrength, compact and stiffness of bolted connections, the preload is generally from50%to70%of the bolt material yield limit in the actual installation process.