New method to restrain superfluous moment of electro-hydraulic moment control system

Aiming at the problem of rejecting to superfluous moment of electrohydraulic moment control system, the advantages and defects of the existent rejecting methods are analyzed. Under the conditions to consider the influence of the inertia of loading side and the stiffness of torque sensor, the dynamic models are established, the conclusion that the superfluous moment is related to the motion velocity, acceleration, and the differential of acceleration is presented. On the basis of this dynamic model, a more effective control method to reject to extraneous moment from the view point of the division and cooperation of the function of the controller, i.e. hybrid control method, is proposed. The experiment of which a kind of electrohydraulic moment load simulator has been developed shows that the law of the superfluous moment acquired by means of identification is in keeping with theoretical result and the new method is of excellent compensating effect to the superfluous moment, so that the quality of the transient procedure is effectively developed.