Active Disturbance Rejection Control for Position Tracking of Electro-Hydraulic Servo Systems under Modeling Uncertainty and External Load

In this paper, an active disturbance rejection control is designed to improve the position tracking performance of electro-hydraulic actuation system in presence parametric uncertainties, non-parametric and external disturbances as well. The observers (Dos) are proposed estimate not only matched lumped uncertainties but also mismatched disturbance. Without velocity measurement, unmeasurable angular robustly calculated based on high-order Levant’s exact differentiator. These integrated into design backstepping framework which guarantees high-accuracy performance. stability analysis analyzed by using Lyapunov theory. Simulations rotary actuator conducted verify effectiveness method.