Dynamic Frequency Study of the Shafting Torsional Vibrations of a Large sized Turbogenerator

On the basis of taking into account the dynamic conditions of a shafting derived was a model of shafting torsional vibrations in connection with dynamic frequency problems. Based on a finite element method the authors have studied the impact of such factors as shafting geometric structure and operating speeds, etc on the shafting torsional vibrations, and thereby developed the criteria for determining the dynamic frequency of multi disc rotor torsional vibrations. In addition, an investigation was conducted of dynamic frequency problems involved in the shafting torsional vibrations of a 300MW turbogenerator. As a result of the investigation, it is concluded that under the condition of existing rotation speeds one can ignore the influence of dynamic frequency for the turbogenerator shafting torsional vibrations.