ESO-based dynamic surface backstepping integral sliding mode control for the speed and tension system of the cold strip rolling mill

Aiming at the tracking control problem of the speed and tension system of the reversible cold strip rolling mill driven by alternating current (AC) asynchronous motors, a dynamic surface backstepping integral sliding mode control method is proposed based on extended state observer (ESO) in this paper. Firstly, the ESOs are constructed to dynamically observe the system's mismatched uncertainties, which effectively improve the tracking control precision of the system. Next, the dynamic surface backstepping control is combined with the integral sliding mode 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 method can guarantee the stability of the closed-loop system in Lyapunov sense. Finally, the simulation research is carried out on the speed and tension system of a reversible cold strip rolling mill through the actual data, and results show the validity of the proposed control method.