Control device and method for damping sinusoidal vibrations of an arrangement and for damping sinusoidal noise on an enclosure

摘要

A method of controlling the application of counter-vibration to a structure (20) so as to reduce the effect of externally-created sinusoidal vibration thereon includes the steps of: mounting a vibratory force generator (19) on the structure; mounting an accelerometer (21) on the structure at a point at which vibration is to be measured; providing a tunable filter (16) capable of resonating at an electrically-controllable frequency; providing an adaptive frequency estimator (22) arranged to produce a tuning signal ( theta ) as a function of the accelerometer output signal (a); supplying the tuning signal and accelerometer output signal to the filter; continuously adjusting the resonant frequency of the filter so as to equal the frequency of the accelerometer output signal so that the accelerometer output signal will be greatly amplified at the filter output; and supplying the filter output signal as an electrical command signal (y) to the force generator; thereby to cause the vibratory force generator to apply counter-vibrations to the structure to reduce the effect of the externally-created vibrations at the measurement point.