Electro-hydraulic servomechanism compensating based on velocity variation caused by torque disturbance

The connecting part of electro-hydraulic servomechanism with load is of high rigidty, so that the output is easily affected by the changes of load and inertia. Besides speed feedback compensating method, it is also an effective method for state feedback of observer reconstruction to decrease and restrain the affect of disturbance of load and inertia. A rotary electro-hydraulic servomechanism is treated by an observer which estimates and measures the disturbance of load and inertia, and the state feedback of observer is reconstructed to form this equivalent closed loop system. By experiments, by analyzing and measuring frequency and step response of this system, it is proved that the changes of speed caused by the disturbance of load and inertia is decreased markedly by this observer, and theoretically the state feedback is correct.