Research On Sliding Problem Of The Bearing Of The Planetary Gear Train Of Wind Turbine And Its Improvement Methods

Along with the rapid development of the wind power industry,therefore higher working stability and reliability of the wind turbine gearbox is in demand.However,due to the uncertainty of wind resources,Some parts,especially bearings,are early damaged due to the frequently variable load and impact load in starting and breaking period.And the working bearings frequently under low load working condition,meanwhile the slipping in the surface of Interference fit between planet gear and the bearings are inevitable,it causes obvious fatigue bruises on the inner surface of the hub.Therefore,it is of great theoretical significance and engineering value to study the surface slip of interference fit between planet gera and the bearings.This paper takes planetary gear transmission system as the object,applying ANSYS software to carry contact finite element analysis,obtained the effects of different interference on the surface of Interference fit between planet gear and the bearings under rated and ultimate loads.Thus put forth to the stress and strain analysis of planetary gear and the bearing outer ring of the optimal-interference fit model.The results show that along with the decrease of the amount of interference,the general trend of the relative slippage of the fitting surface will increase and the fatigue abrasion is getting more serious;In addition,under the effect given by load and interference,the overall variation tendency of the bearing surface is presenting the trend of 'ellipse ',and with the increasing of loads and interference fit,the extrusion tendency of the bearing surface and the ellipse deformation will be more obvious.According to the influence of slip analysis and the assembly between parts and the bearing deformation,the best interference volume of the model is selected,and the ultimate static strength of each part is checked under this interference.It is found that all parts meet the requirements.The interference volume,slip volume and deformation trend of planetary gear bearings are studied,and feasible improvement suggestions are put forward,which has important guiding significance for improving wind turbine gearbox service life and reliability.In non-steady state working condition,the slip in fit surfaces may cause Skid phenomenon.In order to distribute the load of planetary gears evenly,this paper adopted a soft part used in gear train used to compensate for the difference of the gap without any negative effect at the same time,called integrated flexible pin shaft structure.This paper presented its basic structure and working principle.simulated its stress in working condition using FEA software and the results are compared with the results obtained by calculation formula of material mechanics.The comparison result shows that that the error is within the reasonable range.Considering the size of the elastic load balancing mechanism components may have huge influence on its performance,and to make the structure more reasonable,this paper proposed an optimization design of its structure and carried out the optimal size of flexible pin parts of key dimensions.