Influence Analysis Of Static And Dynamic Characteristics Of Wind Power Speed-Increase Gearbox With Tooth Modification

The wind power speed-increasing gearbox as a key component in the wind power generation equipment,static and dynamic characteristics directly determines the performance of wind turbines.Meshing characteristics of gear pair and vibration of the gear transmission system is the main reasons for the failure of the gear box.The tooth modification can relive the vibration caused by the meshing impact,reduce the maximum contact stress,improve the lubrication state of the tooth surface and obtain the uniform load distribution,improving the meshing characteristics of gear pair.Therefore,it is necessary to study the gear modification technology of wind speed increasing gearbox.This research work takes the 2MW speed-increase gearbox of wind power generator as research object.The modification parameters are calculated of each gear pair,the influence of the modification on meshing characteristics of the helical gear pair,the optimization of the modification parameters with gear transmission system,the vibration characteristics of gearbox and comparison and analysis of test.The main research work of this paper is as follows:(1)The tooth surface heat flow is obtained and heat transfer coefficient is calculated,simulation of the temperature of the body of wind speed increasing gearbox.According to the thermal boundary conditions and the load boundary conditions of the wind speed increasing gear box,the gear transmission system thermal-elastic coupling analysis is simulated,and then the meshing in and out interference quantity caused by thermal-elastic deformation of each gear pair is calculated.The gear pair modification value is obtained static conditions.(2)A stiffness correction of time-varying mesh stiffness of helical gears algorithm is used.The feasibility of the modified algorithm is verified by comparing the results with the ISO algorithm and the finite element method.The influence of profile modification on meshing characteristics of gear pair is analyzed based on nonlinear coupling calculation model of gear error and meshing stiffness.(3)The model of wind speed increasing gear box transmission system is established by using the software Romax.Then the transmission error,tooth surface load,stress distribution of gear tooth are analyzed before and after modification.By the tooth profile optimization of wind speed increasing gear box gear pairs with genetic algorithm,minimization of transmission error as the optimization target,the optimal value of modification parameters are obtained.The meshing performance of the wind power speed-increas gearbox before and after optimization modification are contrastively analyzed.(4)A finite element model for the wind speed increasing gearbox is established by ANSYS software,and natural modes of vibration of the gearbox are analyzed by the Lanczos method.The calculated internal dynamic excitations of gear pairs before and after tooth modification are loaded on finite element model,vibration responses of the gearbox before and after tooth modification are solved by mode superposition method.Comparative analysis of vibration responses of the gearbox before and after tooth modification,and the simulation results of vibration have a good agreement with test values,which verifies the correctness of simulation.