电液比例位置同步线性自抗扰控制

电液比例位置同步液压系统受到元件安装精度、死区非线性以及系统参数摄动等因素的影响,导致两侧子系统性能不一致进而引起位置不同步.针对这一问题,提出由位置控制器、死区补偿器、同步控制器组成的复合控制方案.首先,建立电液比例位置控制系统数学模型,并分析系统内部参数摄动及比例阀死区特性对同步控制精度造成的影响.在此基础上,设计线性自抗扰同步控制器,实现对系统内外扰动的实时估计与主动补偿,同时为提高液压缸动态性能,减小稳态误差,设计了比例阀死区补偿器.仿真和实验结果表明,自抗扰控制器有效地抑制了内外扰动,提高了位置同步控制精度,而死区补偿器的引入改善了系统动态响应性能,降低了稳态位置同步误差.

Linear active disturbance rejection control for electro-hydraulic proportional position synchronous

The electro-hydraulic proportional position-synchronous hydraulic system is affected by elements installationaccuracy, dead-zone nonlinearity and system parameter variation, which leads to the performance inconsistency of thesubsystems on both sides and thus causing the position unsynchronization. In order to solve this problem, a compoundcontrol scheme consisting of position controller, dead-zone compensator and synchronous controller is proposed. Firstly,a mathematical model of electro-hydraulic proportional position control system is established to analyze the influenceof internal parameters perturbation and proportional valve dead-zone characteristics on synchronization control accuracy.On this basis, a linear active disturbance rejection synchronous controller (LADRC) is designed to realize a real-timeestimation and an active compensation for system internal and external disturbance, and a proportional valve dead-zonecompensator is employed for the purpose of improving the dynamic performance of the hydraulic cylinder and reducingsteady-state error. The results of simulation and experiment indicte that the LADRC can effectively suppress internal andexternal disturbance, improve the accuracy of position synchronization control. Meanwhile, the introduction of the deadzonecompensation controller can not only improve the dynamic response performance of the system, but also reduce thesteady-state position synchronization error.