Structural Vibration Analysis of Large Turbogenerator

Aiming at the problem that the structural vibration of a large turbogenerator (hereinafter referred to as “generator”) exceeds the standard, the three-dimensional modeling simulation and shutdown modal test of the generator are carried out. The results show that the reason of structural vibration may be the structural resonance caused by the natural frequency of the generator close to the rotor working frequency (50 Hz). Based on the theory and practice of structural resonance, three solutions are proposed to solve the resonance, including increasing the support stiffness, adding the damping vibration absorber and bottom load distribution frequency modulation. Finally, by adding the damping vibration absorber on the generator hydrogen cooler pipe, the bushing vibration at both ends of the generator steam and excitation is greatly reduced, which can ensure that the generator can safely operate for a long time, and solve the long-standing important defect of high generator vibration.