Optimal vibration control for a flexible rotor with gyroscopic effects

Active vibration control of flexible rotor systems with gyroscopic effects is investigated in this paper. Using the finite-element formulation for the mathematical model of flexible rotors, a new rotating velocity-dependent output-feedback controller, in addition to the optimal independent modal-space control system, is proposed to suppress the vibration level and in consequence, achieve better operating conditions. This new active control loop is added in order to compensate the gyroscopic effects during rotation, especially in the higher-flexibility modes. Furthermore, stability analysis via the Kelvin-Tait-Chetaev (KTC) stability theorem for a mechanical system is presented. It demonstrates that if the placement of actuators and sensors are collocated, the fulfillment of optimality and stability for each independently controlled mode is a prerequisite to guaranteeing full-order closed-loop (FOCL) stability. Simulation results are shown in order to confirm that the proposed controller effectively promotes control performance. In addition, the significant impact of the allocation of sensors and actuators on the effectiveness of such a controller is also discussed.