Torsional Vibration Suppression Control in the Main Drive System of Rolling Mill by State Feedback Speed Controller Based on Extended State Observer

In the rolling mill main drive system, a shaft torsional vibration is often generated when a motor and a roll are connected with a flexible shaft. The state feedback control can effective suppress the torsional vibration of the main drive system of rolling mill. Because of the difficulty of measuring the load speed and the shaft torque, moreover the sensitive of Luenberger observer to the model uncertainties and the noise include in the detected signal, in this paper, extended state observer (ESO), a new observer is proposed to estimate the unknown states and the load torque disturbance. ESO based speed controller with an integrator and load torque feedforward compensation for torsional vibration suppression in two-mass main drive system of rolling mill is proposed. The simulation results show the controller effectively improves the performances of command following, torsional vibration suppression, and robustness to parameter variation. It is the first and originative that ESO is utilized in torsional vibration control of the main drive system of rolling mill, and its validity and superiority is verified in comparison with the conventional PI controller and the state feedback controller based on reduced-order state observer.