Analysis on Response of Shaft Torsional Vibration in Turbine-generator Unit

Aiming at the deficiency of traditional model in solving transient response of shaft torsional vibration in turbine-generator unit,a new solution model has been established by eliminating the linear trend and the accumulated error caused by Newmark-β method.Taking a torsional vibration simulator for a 300MW turbine-generator unit as the object of study,simulation analysis was performed on the transient response of the shaft torsional vibration under typical power disturbances,such as the three-phase short circuit,two-phase short circuit and asynchronous juxtaposition etc.Results show that all these disturbances can excite the natural frequencies of the former five steps,of which the 120° asynchronous juxtaposition has the strongest torsional vibration response.Besides,the torsional vibration of the generator rotor is stronger than that of the turbine rotor,over the whole shaft system.