Investigation Of The Hydraulic Servo System Of The Rolling Mill Using Nonsingular Terminal Sliding Mode-Active Disturbance Rejection Control

In order to improve the disturbance rejection ability and tracking accuracy of the hydraulic servo system of the rolling mill, this study combines nonsingular terminal sliding mode control (NTSMC) with active disturbance rejection control (ADRC). A fourth-order extended state observer was designed to estimate the disturbance of the system in real time. The stability of the control system was tested using the Lyapunov method. System effectiveness was verified through simulation experiments. Simulation results showed that the designed state observer can estimate the total disturbance of the system in real time and that the chattering of the control input can be eliminated by the introduction of a state observer. In terms of uncertainty in the system model caused by load changes and external interference signals, the nonsingular terminal sliding mode-active disturbance rejection control method exhibited better disturbance rejection capacity and a higher tracking accuracy than NTSMC.