Viscous Damping Coefficient and Effective Bulk Modulus Estimation in a High Performance Hydrostatic Actuation System using Extended Kalman Filter

Abstract

AbstractIncreasing demands on reliability and safety of fluid power devices have brought much attention to methods for improving condition monitoring of these devices. Whereas faults in hydraulic systems were detected only when limit values of measurable output signals were transgressed, recently, attempts have been made to detect them earlier and to locate them better by the use of measurable signals. The Extended Kalman Filter can be used for real-time estimation of parameters in system models. Changes in model parameters may be tracked and, in turn, be used for determining the condition of the system. In this paper, the Extended Kalman Filter (EKF) is applied to a novel hydrostatic actuation system referred to as the Electrohydraulic Actuator (EHA). A state space model of the EHA is developed and the Extended Kalman Filter is used to estimate unmeasurable but critical parameters such as viscous damping coefficient of the actuator and the effective bulk modulus of the system. The proof of concept of app...