Dynamical Analysis Of Helical Gear Box On 1.5 MW Wind Turbine And Its Tooth Profile Modification

Energy is the most important material basis of the existence and development of human society, in order to reduce the pressure of energy shortage and ensure the smooth and normal development of all the fields of economy, many countries are readjusting the energy structure, and developping new energy sources. As the most clean and green source of energy, Wind energy naturally becomes the focus of national research. Many issues of wind power gear box are increasingly emerging, of which the vibration and noise of gear system becomes an important factor affecting the normal operation of the wind turbine. Therefore, it is significant for improving the performance of wind turbine to study the dynamics of helical gear boxes and its gear profile modification technology.In this paper, dynamic performance and the tooth profile modification of a megawatt-class wind turbine high-speed helical gears are researched and analysised based on the principles and methods of vibration mechanics gear dynamics.First, the bending-torsion-shaft coupled vibration model of a pair of helical gears was created, and modal analysis was carried out; the free vibration response of the system was obtained using formation superposition, then the form of main vibrations was analysised.Secondly, a mathematical model of pure torsional vibration of helical gears was set up,basised on considering the two non-linear factors which is time-varying mesh stiffness and gear backlash, and the displacement, velocity and acceleration of the system's vibration were solved through MATLAB program. The influence of the time-varying stiffness and gear backlash on the torsional vibration performance of the helical gear tooth was analysised too.To the third, the mathematical model of the helical gear with tooth profile modification was established, based on considering the amount of the modification as an internal incentive. The impact of the different parameters on the torsional vibration acceleration was analysised, and then the parameters were optimized choosing the torsional vibration acceleration RMS value as the evaluation index.Finally, the analysis of interface of a helical gear tooth profile modification was designed based on MATLAB/GUI, using which any helical gear parameters could be optimized. Then examples were put into and calculated, the optimization results were derived, and the effect of a few basic parameters on the optimal parameters was analysised.