Study of electro-hydraulic force servo control system based on fuzzy control

Abstract

Because there is flexible load in electro-hydraulic force servo control system, and there is second-order differential section whose oscillation frequency is low in the numerator of the transfer function, the frequency range of the electro-hydraulic force servo control system is influenced badly and the system may oscillate easily even is instability. Aiming at this characteristic of electro-hydraulic force servo control system and the characteristic of the system whose open loop gain is small; the fuzzy control theory is applied to electro-hydraulic force servo control system this typical nonlinear system in order to improve the performance of the system. The models of the system with the fuzzy control theory and without it are built and the simulation and experiment study is done. Comparing the control result of the controller with the fuzzy control theory to the control result of the controller with the traditional PID, and from the results of simulation and experiment, we can find that the controller with the fuzzy control theory can not only increase the frequency range of system, but also improve the precision of system, and the controller can quicken the response ability of the system obviously.