Study on the technology of multiline spectrum control in hybrid vibration isolation system

Periodic disturbances are common in control of vibration isolation systems. Such disturbances may be due to rotational elements such as power plant and vibratory elements. Vibration transmitted from the power plant equipment of a ship to its base causes unwanted noise in the wide frequency band and contains multiline spectrum in the noise spectrum. When the period of periodic disturbances are fixed and known in advance, the proposed control methods, the so-called “multiple repetitive controller” can be used for attenuating their effect. This paper presents some fundamental issues in the design of controllers to deal with periodic disturbances along with applications to hybrid vibration isolation systems of power plant.