| With the more efficient development of the society, the more sustainable consumption of the limited mineral resources, the wind energy, as a clean and pollution-free natural energy, has attracted more and more attention from all over the world, subsequently the wind power industry rises and develops rapidly. So the yaw bearing as a key component of wind turbine has been developed rapidly. Because of the wind turbine, the yaw bearing is installed at the bottom of the cabin, works permanently in the field, has bad working environment, and experiences wind resource of random load and the wind turbine components between the alternating load, the bearing of the yaw is complicated, in addition to the larger bearing size, so the yaw bearing structure parameters optimization and design has always been an obstacle to the rapid development of the wind turbine.The paper takes the 1.5MW wind turbine single row roller yaw bearing as the object, according to the actual running of the yaw bearing, and builds the mathematical modeling firstly using quasi dynamic method of bearing in order to obtain the effects of structure parameters on the mechanical properties, and then the finite element analysis of the bearing is carried out by using ANSYS analysis software, the specific contents are as follows:(1) Firstly the paper used the Hertz contact theory and raceway control theory in the research of the yaw bearing kinematics relationship, set up the coordinates and analysed the motion state and friction of the rolling body, and then established the mathematical model in the motion state based on the quasi dynamic method. The calculation and processes were determined and calculated in MATLAB. The main research is the influence of the load, curvature radius coefficient and initial contact angle on the bearing performance of the yaw bearing. The results show that when the yaw bearing is under load, the actual contact angle is affected by the axial force, and effect by the radial force is small but can change its overall distribution; the larger the initial contact angle, the better the bearing performance, However, if the initial contact angle is too large, the contact area is close to the edge of the rolling track,resulting in the bearing damaged; The greater the radius of curvature of the groove, and the greater the maximum load of the rolling body, so the groove curvature radius coefficient should be between 0.51 to 0.52 values to increase the bearing capacity.(2) The paper obtained the yaw bearing structure parameters based on quasi dynamics equations, selected the 3D drawing software UG building the bearing of the overall model and the imported the ANSYS software, in the finite element software we took 1/32 of the model in the static simulation analysis, and obtained the contact area of the inner and outer rings and rolling bodies and displacement maps. Compared the results of the third chapter using the kinetic and the classical Hertz contact theory with the results of the finite element analysis, we found the results are similar, and the smaller error verifies the finite element model to establish a correct and the basis of modal analysis in bearing.(3) Using ANSYS static analysis model and the results of the model analyze the modality of the bearings, we obtained the first 8 order modes, then we analyze, and prevent the occurrence of the resonance in the normal operation which can result in the larger internal structure of the deformation and thereby affect the normal use of the bearing. The results show that the deformation and vibration of the yaw bearing in the initial stage of the oscillation occurs mainly in the rolling body, and it will spin around its own axis; The natural frequency of the bearing is 7982.8Hz when the maximum deformation of the bearing is 3.527 mm,; Before and after the first and then swing bearing swing, the former is slightly larger than the amplitude of the latter... |
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