Nonlinear ODE Parameter Identification of Electro-hydraulic servo system Based on Trust-Region Optimization Algorithm

In view of the strongly nonlinear characteristic of electro-hydraulic servo system (EHSS), this paper aims to conduct nonlinear ordinary differential equation (ODE) parameter identification of white-box model based on the knowledge of part of the system information so as to get the accurate nonlinear model that can meet the actual needs. By establishing the state space model of the hydraulic system in theory and determining the parameters to be identified, the issue of parameter identification of the system is converted into that of parameter optimization based on output error, and based on trust-region optimization algorithm, the accurate state space model of the system both in no-load and load cases is created; the final test verifies that the nonlinear modeling based on ODE parameter identification is more accurate and effective.