With the fast development of wind industry

the wind turbine power per unit is increasing rapidly and the offshore turbine power per unit even reaches 6MW level above. An investigation on large turbine drivetrain is conducted in order to improve its robustness and reliability. Based on macro & micro geometric parameters of gear and transmission dynamics

as well as taking time- varying transmission errors into consideration

the multi- megawatt wind turbine drivetrain RomaxWIND model is built. By fully considering the complex boundary conditions and the external and internal factors of the wind turbine drivetrain

based on the aralysis of the modality and energy of the system

the incipient fault of the sympathyetic vibration of the drivetrain is investigated

and the sensitivity of the motivation and the dicdutructive effect are evaluated. Considering the effect of the transient motivation

such as the impact of the wheel hub

the response of the offset and the force of the bearing is studied

the results provide the reference for the reliability assessment of the wind turbine drivetrain.