State Estimation and fult detection in hydraulic pump using nonlinear Observer

In this research, parameter estimation and fault detection in hydraulic pump which is one of the most common systems used in sensitive industries such as aerospace and it has nonlinear behavior is investigated. The detection criterion is the residual signal calculated from the difference between the system output and an unknown input parameter. The reason for using the nonlinear observer is the timely detection of faults and its resistance to model disturbances and uncertainties. In this research, the leakage in the pump and the change of swashplate angle of the hydraulic pump are considered as faults and they could be detected by a nonlinear observer in time. Finally, it is proved by Matlab simulation software that the proposed method is able to estimate the system states well and reveal the faults.