Abstract:In order to improve the tracking accuracy of hydraulic servo system for target position,a hybrid model predictive controller for position tracking of hydraulic servo system was designed.Firstly,the kinematics model of hydraulic cylinder and servo valve was established by modeling the hydraulic servo system and analyzing its structure.Then,the working state of the traditional model predictive controller was analyzed,and its corresponding linear time-invariant model was obtained.On the basis of the traditional model predictive controller,a hybrid model predictive controller was designed by using the improved PID controller based on cuckoo search algorithm.Finally,the target position trajectories generated by step,square wave and irregular signal were tracked by the hybrid model predictive controller.The test results show that the designed hybrid model predictive controller can not only track target position trajectory generated by multiple signals,but also track accurately with higher accuracy and less volatility.Compared with the tracking results of traditional model predictive controller,the maximum deviations of hybrid model predictive controller are reduced by 6.77%,17.39% and 19.64% respectively when tracking the target position trajectory generated by step,square wave and irregular signal.It shows that the designed hybrid model predictive controller can control the hydraulic servo system to track the target position well.