Disturbance observer based position tracking of electro-hydraulic actuator
来源期刊：中南大学学报(英文版)2015年第6期
论文作者：GUO Kai WEI Jian-hua TIAN Qi-yan
文章页码：2158 - 2165
Key words：electro-hydraulic system; single-rod actuator; disturbance observer; external disturbance; parameter uncertainty
Abstract: A nonlinear controller based on an extended second-order disturbance observer is presented to track desired position for an electro-hydraulic single-rod actuator in the presence of both external disturbances and parameter uncertainties. The proposed extended second-order disturbance observer deals with not only the external perturbations, but also parameter uncertainties which are commonly regarded as lumped disturbances in previous researches. Besides, the outer position tracking loop is designed with cylinder load pressure as output; and the inner pressure control loop provides the hydraulic actuator the characteristic of a force generator. The stability of the closed-loop system is provided based on Lyapunov theory. The performance of the controller is verified through simulations and experiments. The results demonstrate that the proposed nonlinear position tracking controller, together with the extended second-order disturbance observer, gives an excellent tracking performance in the presence of parameter uncertainties and external disturbance.
GUO Kai(国凯), WEI Jian-hua(魏建华), TIAN Qi-yan(田启岩)
(State Key Laboratory of Fluid Power Transmission and Control (Zhejiang University), Hangzhou 310027, China)
Abstract:A nonlinear controller based on an extended second-order disturbance observer is presented to track desired position for an electro-hydraulic single-rod actuator in the presence of both external disturbances and parameter uncertainties. The proposed extended second-order disturbance observer deals with not only the external perturbations, but also parameter uncertainties which are commonly regarded as lumped disturbances in previous researches. Besides, the outer position tracking loop is designed with cylinder load pressure as output; and the inner pressure control loop provides the hydraulic actuator the characteristic of a force generator. The stability of the closed-loop system is provided based on Lyapunov theory. The performance of the controller is verified through simulations and experiments. The results demonstrate that the proposed nonlinear position tracking controller, together with the extended second-order disturbance observer, gives an excellent tracking performance in the presence of parameter uncertainties and external disturbance.
Key words:electro-hydraulic system; single-rod actuator; disturbance observer; external disturbance; parameter uncertainty
