The Research Of Intelligence Control Based On Neural Networks In Electro-hydraulic Servo System

Electro-hydraulic servo control systems are widely used in industrial fields because the systems are possessed of high accuracy, quick response and easy adjustability, in the same time, the systems can control large inertial-mass and realize large power output. But, electro-hydraulic servo system is nonlinear system in essence and exists time- variation parameters and uncertainties resulted from external disturbance, which makes that the dynamic characteristics of system are very complicated and the accuracy mathematic model of the system is established difficultly. The controller designed by using traditional method based on model is of poor adaptivity and anti- disturbance, which is not adaptive to nonlinear and time-variant systems and fails to acquire satisfying control effect.Intelligence control has achieved substantial development in theory and application technology.In industrial control fields, because neural networks are possessed of self-learning adaptiveability and mighty nonlinear match ability, it offers a effective solving method for nonlinear system modeling. Though conventional PID control based on accuracy model is possessed of simple structure, good robustness and high reliability, it is difficult to get the precise parameters of PID controller. Combining neural network technology with conventional PID control technology can utilize on-line identification ability of neural network to solve effectively regulation problem of single-neuron PID parameters, which implements intelligence control of system.In the paper, the intelligence control based on neural network in electro-hydraulic position servo system is explored usefully. Firstly, on the basis of analysis of system characteristics, the paper researches on neural network identification technology for establishing on-line dynamic model of system. Secondly, the paper designs controller based on PID adaptive control strategy according to the dynamic model. The strategy is used to reduce disadvantageous influence caused by nonlinearities and uncertainties of electro-hydraulic servo system. Simulation and experiment show that the control strategy can improve dynamic characteristics of system, minimize stable state error of system, enhance adaptive ability and anti-disturbance ability of system, and meet performance request of system.