A Novel Tracking Control Strategy With Adaptive Noise Cancellation for Flexible Rotor Trajectories in Lubricated Bearings

This article proposes a frequency-dependent adaptive noise cancellation-based tracking controller for the trajectories' stabilization of a flexible rotor supported on full lubricated journal bearings. The aim is to provide a general solution to the control problem by introducing a modular and closed-form formulation. Starting from the medialization of the journal bearings nonlinear fluid film forces acting on the rotor during the motion, a manual matrix solution of equations is achieved. The formulation takes in account the journal bearing lubricating problem in terms of both cavitated and uncavitated short bearing analytical solutions. The adaptive vibration-reducing tracking controller is based on a quick online estimation of the mutual forces acting on the rotor, in the presence of the imposed frequency disturbances, under the assumption of a known exosystem dynamics. The controller acts as a force observer and modal disturbance estimator. Then, it is independent of the operating conditions of the bearings. A mathematical proof and numerical simulations are provided to validate the proposed control. The control response results very fast.