FTESO-based Nonsingular Fast Integral Terminal Sliding Mode Finite Time Control for the Speed and Tension System of the Cold Strip Rolling Mill

To weaken the influences of uncertainties on the finite time tracking control performance of the speed and tension system of the reversible cold strip rolling mill driven by alternating current (AC) asynchronous motors, a dynamic surface backstepping nonsingular fast integrated terminal sliding mode control (DSBNFITSMC) strategy is proposed based on finite time extended state observers (FTESOs). Firstly, the FTESOs are constructed to dynamically observe the system’s mismatched uncertainties, and the observation errors can converge to zero in finite time. Next, the dynamic surface backstepping control is combined with the nonsingular fast integrated terminal sliding mode finite time control to complete the controller designs for the speed and tension system of the reversible cold strip rolling mill, which solve the “differential explosion” problem in conventional backstepping control, and simplify the design processes of the system controllers. Again, theoretical analysis shows that the proposed control strategy can guarantee the closed-loop system is practical finite time stability in the Lyapunov sense. Finally, the simulation research is carried out on the speed and tension system of a reversible cold strip rolling mill by using the actual data, and results show the validity of the proposed control strategy.