The Development Of Ultra-low Speed Hydraulic Press Control System

With the development of China National Defence Industry, the Titanium-Alloy is applied in a lot of fields. The hydraulic press must meet the need of the metal forging, in which the press must carry out the Ultra-low speed control, improving the metal performance. Considering the application of the Ultra-low speed press, the control system should be developed with an advanced control strategy.The dissertation introduces the development of press and press control system. Also it brings forward the key technology and the research content. The deep analyse is taken on structure and principle. Since the pipeline influences the press performance, a nonlinear press model, including the pipeline model, is built. An M/T speed measurement which is a variable sampling-period method is used to achieve the Ultra-low speed sampling.Furthermore, the dissertation takes a research on the nonlinear character and variable sampling-period discretization of press model. The press control system adopts the Fuzzy Self-adaptive Tuning PID control strategy. The Fuzzy control rules is come from the experience and discrete-continue simulation. The simulation system is built in MATLAB environment. And, the result shows that Fuzzy Self-adaptive Tuning PID control has a better performance.In application, the press control system is developed on the IPC and the PLC. The programme of M/T Ultra-low speed measurement and Fuzzy Self-adaptive Tuning PID control strategy is realized in PLC controller. The actual result shows that the control system can carry out steady control in the Ultra-low speed of 0.002mm/s. It makes a top class performance among the same kinds of systems in our country.