Simultaneous Optimum Design of Shaft Configuration and Damper in Torsional Vibration of Turbogenerator Rotor Set.

In the turbogenerator rotor set, the transient torsional vibration induced by short circuits in the generator and ground faults in the electric network by lightning strikes can lead to not only material fatigue but also occasional breakdowns of the turbogenerator rotor. In this paper, a dynamic damper is attached to the rotor in order to suppress the transient torsional vibration. Applying the traditional design approach, the shaft configuration is not modified to enhance the vibration suppression performance of the dynamic damper. This paper aims at proposing a simultaneous optimum design approach in which both shaft configuration and dynamic damper are designed simultaneously. In the numerical example, a model of the turbogenerator rotor set which is composed of HP, LP1, LP2 turbines and a generator is designed. The results indicate that the transient torsional vibration is well suppressed by dynamic damper, and vibration suppression performance is augmented by applying the simultaneous optimum design approach.