In order to analyze the vehicle dynamic behavior caused by the inner dynamic excitation of driving gear

the time-varying stiffness of meshing teeth pairs is calculated through finite element analysis at first.Transmission error curve is computed according to profile tolerance which is determined by the machining precision of gearing.With above results

the inner dynamic excitations including stiffness excitation and error excitation are obtained

it is loaded into the dynamical equations of vehicle system.At last

a non-linear dynamics model of the high speed train including the inner dynamic excitation system is established.The results show that the inner gear dynamic excitation has little effect on the vibration of bogie frame and carbody

but has some effect on the tractor motor and gearbox

especially on the lateral and vertical direction.When the bogie frame is regarded as flexible body

the effect is more obvious.