电动静液作动器的新型变阻尼级联滑模控制

Aimed at improving the performance of an Electro-Hydrostatic Actuator (EHA), a novel Cascade Control (CC) algorithm based on Damping-Variable Sliding Mode Control (DV-SMC) and PID is proposed in this paper. A high-order model of EHA was divided into two low-order subsystems, i.e. mechanical subsystem and hydraulic subsystem. Furthermore, double-loop PID and DV-SMC were applied for the two subsystems, respectively. The proposed method can adjust the damping ratio of the subsystem adaptively. At the beginning of sliding, small damping ratio was used, while an overdamped subsystem was obtained in the end by adaptive adjustment. Therefore, the EHA rapidness and the suppression of overshoot can be guaranteed simultaneously. Finally, simulative validation was carried out to verify the effectiveness of the proposed method, and the optimal parameters of the sliding mode surface are discussed and given.