Backstepping sliding mode control for continuous casting mold vibration displacement system driven by servo motor

Adaptive High-order Sliding Mode Control for Vibration Displacement System of Continuous Casting Mold

“…However, there is a nonlinear periodic function ,i.e., sinusoidal function, between the vibration displacement of the mold and the angular displacement of the eccentric shaft in the forward channel of the CCM system. The nonlinear periodic function of the output equation has the non-unique problem of inverse solutions [5], which will bring difficulties to the controller design for tracking the desired vibration displacement. At the same time, there are unknown uncertainties in the CCM system, such as the initial deviation of eccentric shaft mechanical zero position, parameter perturbation, and varying-time load disturbance, etc., which make it difficult to improve the tracking control accuracy.…”

“…However, it was still complex to realize displacement tracking control by using the above method for the vibration displacement system of the CCM driven by a servo motor. In [5], [8] and [9], a piecewise mapping function method was proposed, and the mapping relationship  between eccentric shaft angular displacement and mold vibration displacement is established, which can simplify the displacement tracking control and facilitate the design of the controller because the problem of vibration displacement tracking is transformed into the problem of angular displacement tracking. However, these methods depend on accurate judgment of the extreme points of the CCM vibration displacement system.…”