Research On The Electro-hydraulic Position Servo System Of The Precise Straightening Press

The hydraulic-servo system of the precise straightening press is the executive body and is the key unit to ensure the processing precision of the workpiece. In this dissertation, the basic theory of hydraulic-servo system is explored further more, the electro-hydraulic position servo system of the precise straightening press is researched entirely, combined the theory of modern control and the theory of adaptive control with the theory of electro-hydraulic servo control. The main contents are as following:1.According to the basic theory of hydraulic-servo system, research deeply the mathematical modal of four-connection valve-controlled hydraulic cylinder, built up the transfer function of four-connection valve-controlled hydraulic cylinder and analyze it's dynamic character.2.Research the electro-hydraulic position servo system of the precise straightening press under different load by applying the method of transfer function. Firstly establish it mathematical modal, research the affect of the system character by the system parameter and bring forward the method improving system character when the load is outside power. Then research the affect of the system character by the different load stiffness and the relation between load stiffness and the amplifier gain, bring forward a method of adjusting the amplifier gain dynamic to improve the system character. Lastly based on establishing it discrete mathematical modal, research the system character and the choose of system parameter on the electro-hydraulic position servo system of the precise straightening press controlled by compute.3.Develop the experiment system of the electro-hydraulic position servo system of the precise straightening press and the experiment research is carried on by the different load.4.Establish it state space modal by applying the theory of modern control to electro-hydraulic position servo system, and bring forward the method of quadratic optimal control and approach track optimal control.5.Applying the theory of adaptive control to electro-hydraulic position servo system, bring forward a adaptive control method based on regulating gain and damp, a adaptive control method of approach track based on parameter identification, a self-tuning control method of pole placement, a adaptive control method of general predictive.The research contents in the dissertation provide the theory support in developing state-produced automatic straightening press.