Research On Load Port Independently Controlled Double Servo Valves Cylinder System

With the continuous development of industrial technology，the electro-hydraulic servosystem has been more widely used in the fields of aerospace, weapons, metallurgy,machinery, etc. The load port independently controlled double servo valves cylinder systemnot only has the electro-hydraulic servo system’s high accuracy, high load capacity features;but also solves the problem that the controller can’t reach the best effect under the conditionof negative load. At the same time, it could correct the imperfection of the control accuracyturn low because of the velocity gain mutation when using a single symmetrical valve tocontrol an unsymmetrical cylinder.Firstly, this article describes the basic structure and working principle of the system,and establishes the model of the load port independently controlled servo valve cylindersystem. By comparison with the conventional servo valve cylinder system’s mathematicalmode, the ways to improve the system damping ratio are analyzed. Different workingmodes for the condition of positive and negative load are designed. A detailed discussion onthe typical flow controller and pressure controller for the double servo valves cylindersystem is made, and a correlation analysis on the steady-state accuracy and dynamicstability is given. When the servo valve control the flow and pressure, there will benonlinearity. The nonlinear link of the system is studied, and a compensation matrix torealize the system’s observability and dynamic stability is designed.On the control arithmetic, this article propose a self-adaptive robust control algorithmvia the static operation point. This control algorithm can improve control accuracy underthe condition of positive and negative loads. This algorithm is proved to be asymptoticallystable. Furthermore, a joint simulation using AMESim and Matlab to this double servovalves cylinder system is made. Simulations and analysis for this system are made.Furthermore, this article design a system drive circuit based on the PC/104control unit, andset up a experimental platform for the load port independently controlled valve cylindersystem. Experiments and analysis for this system are made.