连续性电液伺服系统位移轨迹的滑模跟踪控制

Sliding mode tracking control of displacement trajectory ofcontinuous electro-hydraulic servo system

为解决电液伺服系统在零位附近运动时,系统跟踪活塞杆位移轨迹出现抖振问题,提出一种改进连续性电液伺服模型,采用滑模控制方法设计切换超平面和趋近律,在同一大气压下,建立电液伺服系统滑模跟踪控制器,将连续性电液伺服系统和传统的电液伺服系统进行建模仿真,分析电液伺服系统位移轨迹的跟踪控制精度。结果表明,在活塞杆位移跟踪轨迹时,相比传统电液伺服系统,连续性电液伺服系统平滑了2 kHz的抖振现象,且位移跟踪精度提高了5%。

This paper disscusses the efforts to address the displacement trajectory chattering of tracking piston rod when electro-hydraulic servo system moves near zero position and proposes an improved continuous electro-hydraulic servo model.The study involves designing a switching hyperplane and a reaching law using sliding mode control method;establishing a sliding mode tracking controller of the electro-hydraulic servo system under the same atmospheric pressure;simulating to analyzing the continuous electro-hydraulic servo system and the traditional electro-hydraulic servo system;and analyzing the tracking and control precision of the displacement trajectory of the electro-hydraulic servo system.The results show that,compared with traditional electro-hydraulic servo system,the continuous electro-hydraulic servo system smooths the buffeting phenomenon of 2 kHz with the displacement trajectory tracking of the piston rod,and the tracking accuracy of displacement increases by 5%.