The Improved Design And Simulation Of The Electro-hydraulic Step Cylinder With Built-in Servo Valve

The object of this paper is a kind of electro-hydraulic stepping cylinder used for continuous casting mold oscillation. According to its structure, working principle and performance parameters, Though calculating the hydraulic parameters, structural parameters and performance parameters, the specific structure of the electro-hydraulic stepping cylinder has been designed, and its3D assembly model has been built by used Solid Works.According to the electro-hydraulic stepping cylinder working principle, it can be divided into two parts, the step motor part and the three links servo valve-regulated non-symmetrical cylinder part, and its nonlinear mathematical model was built using the simulink in Matlab.Based on this nonlinear mathematical model, a detailed analysis of the static and dynamic performance of electro-hydraulic stepping cylinder was be made. Some suggestions for improvement has been proposed though comparative analysis by changing some key parameters of the mathematical model.In order to eliminate the defects of the open-loop controlled electro-hydraulic stepping cylinder, closed loop control system with PID controller for the electro-hydraulic stepper cylinder has been built to improve the static and dynamic performance of electro-hydraulic stepping cylinder, but the result is not satisfactory. So a fuzzy adaptive PID controller with general rules was tried, and it has been used in this closed loop control system. The simulation results improved that the performance of electro-hydraulic stepping cylinder can be improved significantly.In order to test the actual performance of electro-hydraulic stepping cylinder, a test platform has been built including mechanical structure, hydraulic systems, electrical structure, software structure and the test content and process.