Abstract: For large flexible supporting characteristics of wind turbine tower for wind machine nonlinear dynamics of gear transmission system,using the theory of vibration mechanics includes tower stiffness,time-varying mesh stiffness,mesh damping and wind turbines with factors such as backlash nonlinear dynamic model of gear transmission system to solve the nonlinear dynamics research of flexible supporting the vibration characteristics of wind turbine gear system based on 4-5 order variable step kuta long lattice.Based on the current domestic mainstream 1.5 MW wind turbine gear system is analyzed,gaining kinetic characteristics of wind machine in the tower under wind loading,and wind turbine gear transmission system of the secondary parallel shaft helical gear transmission system .Under the effect of wind load,the results show that wind turbine gear under the flexible supporting system vibration is more intense;decrease the value of the wind turbine tower stiffness,wind turbine gear relative torsional vibration response by the period-doubling bifurcation into the mix-up movement.

Key words: wind turbine, flexible support, transmission gear, nonlinear dynamics