Active Vibration Control of a Rotor Bearing System Using Piezoelectric Patch Actuators and an LQR Controller

Abstract

Active vibration control (AVC) is used to overcome the limits of passive control. This chapter presents a design of an active vibration controller for a rotor bearing system using active piezoelectric patch actuators bonded on the surface of the rotor shaft. These devices are used to compensate the unbalance forces by applying control moments. The finite element method is used to construct a discrete rotor bearing system model. The design uses proximity probes to measure lateral vibration of the rotor bearing system. A Linear quadratic regulator (LQR) controller based on a full state feedback is designed to provide the adequate activation power to the piezoelectric patches. Rotordynamic analysis is carried out to obtain the Campbell diagram, the natural frequencies, and the critical speeds of the rotor bearing system. The designed active vibration controller reduced significantly rotor lateral vibration at constant rotating speed. A higher reduction rate has been obtained at the first critical speed.