Development of advanced algorithms for displacement, velocity and pressure control of electro-hydraulic systems

Hydraulic motion drives are widely used in several areas of industry, especially in applications that require high forces or torques. While typical hydraulic systems have relatively simple mechanical components, they are characterized by nonlinear dynamics, specifically, a square-root relationship between the differential pressure that drives the flow of the hydraulic fluid and the flow rate.; Most commercially available industrial controllers use PID control for force, velocity and displacement control in hydraulic systems; however, their performance is limited due to the nonlinear nature of these systems.; In this study, we use the technique of feedback linearization method to overcome the effects of the nonlinearity. Using this nonlinear control approach, we develop advanced controllers for angular displacement, angular velocity and pressure control of a rotational hydraulic drive, and test the performance of feedback linearization based controllers through simulation & experimental testing on a hydraulic test-bench.