Design of Sliding Model Active Disturbance Rejection Controller for Hydraulic Position Servo System

A position control method for hydraulic servo system of continuous casting mold is studied.Because the system has large extent of model uncertainties including big changes in load and hydraulic parameters,which are unmatched,so it is very difficult to control very well.An approach active disturbance rejection control combined with sliding mode control is proposed.The extended state observer is used for observing internal parameters uncertainties and external disturbances,so that the uncertain of the system is decreased efficiency.Using the actual parameters simulation,the results show that the control approach has nice global robustness and improves position tracking accuracy.