电动静液作动器的非线性变阻尼积分滑模控制  

Nonlinear variable damping integral sliding mode control for electro-hydrostatic actuator

作　　者：杨荣荣[1] 张玲[1] 赵家黎[1] 付永领[2] 张朋[3] YANG Rongrong;ZHANG Ling;ZHAO Jiali;FU Yongling;ZHANG Peng(School of Mechanical and Electrical Engineering,Lanzhou University of Technology,Lanzhou 730050,China;School of Mechanical Engineering and Automation,Beihang University,Beijing 100191,China;Beijing Research Institute of Precise Mechatronic and Controls,Beijing 100076,China)

机构地区：[1]兰州理工大学机电工程学院,兰州730050 [2]北京航空航天大学机械工程及自动化学院,北京100191 [3]北京精密机电控制设备研究所,北京100076

出　　处：《北京航空航天大学学报》2024年第1期163-172,共10页Journal of Beijing University of Aeronautics and Astronautics

基　　金：甘肃省科技计划项目(20JR10RA175)。

摘　　要：对于电动静液作动器(EHA),传统滑模控制器存在加速度信息难以获取,参数不易整定和控制信号抖振等问题,从而造成控制器很难应用于实际。针对以上问题,利用奇异摄动理论对EHA数学模型进行合理的降阶,从而使控制器设计避免了使用加速度信息。在此基础上,利用降阶模型设计了一种新型非线性变阻尼积分滑模控制器(NSMC),该控制器可根据位置控制误差实现系统阻尼比由欠阻尼到过阻尼的自适应调节,能有效提高位置阶跃调节性能。设计了一种基于滤波器的不确定项估计器对EHA中存在的参数不确定性和外部扰动进行实时估计并补偿。滑模面积分项的引入和不确定项估计器的使用,一方面使控制器中无需使用切换函数,实现了EHA的无抖振滑模控制,另一方面使系统整个动态过程完全表现为滑动模态,从而可根据EHA控制指标直接整定滑模面参数,大大简化了参数整定过程。同时利用Lyapunov稳定性理论对整个闭环系统和滑模面的稳定性进行了详细分析。分别与PI控制器、传统滑模控制器(SMC)和传统变阻尼滑模控制器(DVSMC)进行了详细的仿真分析比较,仿真结果表明NSMC能有效提高EHA位置跟踪性能和增强对参数不确定性和外部扰动的鲁棒性。For electro-hydrostatic actuator(EHA),the traditional sliding mode controller has many defects,such as control signal chattering,difficulty in acceleration information acquirement and controller parameters tuning,which make the controller difficult to be applied in practice.To solve the above problems,the reduced order mathematical model of EHA is obtained reasonably by using singular perturbation theory,which result in avoiding the use of acceleration information.On this basis,a novel nonlinear variable damping integral sliding mode controller(NSMC)is synthesized by employing the reduced order model.NSMC can adaptively adjust the system damping ratio from underdamping to overdamping according to the position control error,and can effectively improve the position step performance.Besides,filter-based uncertainty estimator is designed to estimate and compensate the parameter uncertainties and external disturbances of EHA in real time.Due to the introduction of sliding mode surface integral term and uncertainty estimator,switching function is unnecessary,on the one hand,the free-chattering sliding control can be achieved.On the other hand,the whole dynamic process is determined directly by the dynamic of sliding mode surface,so that sliding mode surface parameters can be tuned directly according to EHA’s control performance index,which greatly simplifies the parameters tuning process.Meanwhile,the stability of the whole closed-loop system and sliding mode surface is proved via Lyapunov stability theory.Finally,by comparing respectively with PI,conventional sliding mode(SMC)and damping variable sliding mode controller(DVSMC),the simulation results indicated that NSMC can effectively improve EHA position tracking performance and enhance the robustness of parameter uncertainty and external disturbance.

关 键 词：电动静液作动器 奇异摄动 变阻尼 积分滑模控制 不确定项估计器 

分 类 号：TH137[机械工程—机械制造及自动化]