Active vibration control applied to a vacuum pump for high precision equipment

This paper presents results of a system for active vibration reduction on a setup with a vacuum pump that is tightly coupled with high-precision equipment. The precision of this equipment is critically dependent on the level of the vibrations that are introduced by the vacuum pump. The vibrations were reduced by a recently developed adaptive control scheme in a multi-input multi-output feedback configuration using a sampling rate of 12 kHz. The convergence properties of this algorithm allowed effective tracking of the varying excitation spectrum. Programmable digital minimum-phase reconstruction and anti-aliasing filters at a sampling rate of 100 kHz were used for an optimal tradeoff between sampling errors and phase shift. Effective broadband control was obtained in the frequency range of 100 Hz to 5 kHz, leading to 11.3 dB average broadband reduction on the error sensors.