| The control of electro-hydraulic servo-systems has received considerable attention in recent years. This is because electro-hydraulic systems are able to generate high loads with very fast response times using servo-valves to provide accurate control. In addition, they are able to maintain their load capacity indefinitely, in contrast to electrical systems which are prone to excessive heat generation. Electro-hydraulic systems are widely used in many industries such as industrial automation, robotics, manufacturing and mining, as well as other special purpose applications.;In this study, we use adaptive pole-placement control to improve the controller performance for electro-hydraulic systems. The approach is as follows: (1) The recursive least-squares algorithm (RLS) is used to identify the plant parameters. (2) These estimated parameters are used to design a linear pole-placement controller. The performance of the proposed control algorithm is evaluated by simulation using Matlab/SimulinkRTM.;Keywords: electrohydraulic system, nonlinear control, PID, adaptive control, pole placement;While typical hydraulic systems have relatively simple mechanical components, they are characterized by non-linear dynamics, in particular, a square-root relationship between the differential pressure that drives the flow of the hydraulic fluid and the flow rate. Most commercial controllers for industrial electro-hydraulic systems are based on PID control and use gains obtained by linearizing the system dynamics around a fixed operating point. Thus, they have performance limitations due to the presence of nonlinearities and also due to imprecise knowledge of the system parameters. |
