Method and system for tuning a frequency of a rotating body

摘要

A solution is provided for tuning the frequency of a torsional mode of interest of a rotating body (100) (such as a generator rotor (100) torsional mode) by adding a detuner (106) to act as an undamped torsional vibration absorber. The detuner (106) may be coupled to an overhung shaft (105) extending from the rotating body (100). The detuner (106) may be modular, therefore weight can be added or subtracted easily from the detuner (106) in order to adjust the stiffness and/or inertia of the overhung shaft (105). This change in stiffness and/or inertia yields a torsional frequency of oscillation in the overhung shaft (105) substantially similar to the natural frequency of the torsional mode of interest of the rotating body (100), therefore forcing the frequency of the torsional mode of interest of the rotating body (100) above or below its torsional natural frequency.