Design And Control Analysis Of Hydraulic System Of Oscillating-plate Necking-in Machine For Special Surface

This article introduces a necking-in machine, which is improved according to one kind of the existing machines for "the thin-wall hollow tube and named for oscillating-plate necking-in machine for special surface, after learning about the necking-in principle and methods. The hollow tube can be processed into not only spherical surface, but also tapered, saucer-shaped, bowl-shaped, parabolic surface, etc. Besides, this machine is highly automated because it is control by the electro-hydraulic proportional system.The working principle of this machine is introduced in details in this article, and then the hydraulic system is designed and the component is select according to the processes. The mathematical model of the hydraulic control system is built separately in the positive and negative direction. This model not only can embody the dynamic performance of the system, but also provide the theoretical reference for the obtaining of the accuracy parameters of the system and component.It is necessary to analyze the performance of the system after designing the control system for further improvement. The Matlab/Simulink software is applied for the system simulation, and then the simulation results are analyzed according to the obtained simulation curves which reflect the dynamic performance of the system.DSHplus is a kind of hydraulic-pneumatic-control simulation software with graphical programming environment and abundance of model libraries, so the designer can build the system model quickly. And it is very convenient to adjust the system parameters which can be observed in real-time when applying the DSHplus softsware. However, some complex control algorithm is difficult to complete because some function is restricted, such as fuzzy control. The good thing is DSHplus provides the interface with Simulink, which makes it possible for further research. The PID controller, fuzzy controller and the fuzzy PID controller are applied to improve the dynamic performance of the system, and the simulation results show that the three controllers can also improve the response capability and steady state performance. By contrast, the fuzzy controller is superior to the conventional PID controller and the fuzzy PID controller is the best.