Computationally Efficient Non-linear Electro-hydraulic Actuation System Model for Real-time Simulation

Abstract

An electro-hydraulic actuation system with critically lapped servovalve and pressurized return line is exposited. The dynamic equations governing the behavior of various components are explained; using these nonlinear equations, a simulation model is developed in Simulink® software for the purpose of controller design and verification. Model requires very small integration step size as the equations involved are stiff. A relationship between the various pressures in the system is derived, and a simplified method for the nonlinear modeling of electro hydraulic actuating system is developed using these relationships. The simplified model is computationally efficient as the integration step-size is large compared to the original model. The computationally efficient model finds application in real-time hardware-in-loop simulation (HILS).