Fuzzy Neural Network Control For Electro-Hydraulic Roportional Pressure System

Electro-hydraulic proportional system is one of the ordinary and essential electro–hydraulic systems in the industry and scientific research. Electro-hydraulic proportional system is applied to many areas of the society. Electro-hydraulic proportional system is a typical system which is coupled with mechanical technology, electric technology and hydraulic technology. Non-linearity, non-confirmation, outside and across disturbances are existed prevalently in the electro-hydraulic proportional system and the accurate mathematic model of the system is established difficultly. The traditional PID control theory can't solve the control problem on the electro-hydraulic proportional system, so we must find a new control tactic immediately.With the progress of science and technique, the theory of control is developing too. Fuzzy control and neural network control is new control technique. In this paper, the combination of fuzzy control and neural network control is applied to the electro-hydraulic proportional system. The structure,arithmetic and application of fuzzy control and neural network control are analyzed systemically. Used the merits of fuzzy control and neural network control, the technology of fuzzy control with neural network-based is created. The layer and node of neural network are corresponding to every part of the fuzzy system, and the rules of fuzzy control are distributed in the whole network impliedly, so that fuzzy reasoning is implemented by neural network. Fuzzy control is sufficiently used in this control strategy, it is according with the intuitionistic description and logistic thought. At the same time, the method solves the problem that the parameters of neural network is difficult to understand because the parameters don't have precise sense.This paper is based on the material testing machine. The mathematic model of the electro-hydraulic proportional system of pressure on the machine is confirmed by system identification. Used the software MATLAB/Simulink, the PID controller and the fuzzy neural network controller were created, and modeled and simulated for them. Then, through the semi physical simulation software of dSPACE, the control strategy of theelectro-hydraulic proportional system of pressure was realized in experiment and proofed. The results indicate: compared with the PID control, the fuzzy neural network control has more merits, such as better robustness, letter overshoot and more powerful self-adapting capability, etc.