针对电液伺服系统在间歇激励条件下的高精度轨迹追踪问题提出了一种复合自适应动态面控制方法.通过引入一阶指令滤波器对控制器设计过程中的虚拟控制信号进行处理，可以避免对其进行复杂的偏微分计算.为了实现对液压系统中未知阻尼系数与未知刚度系数的估计与补偿，设计了一种复合自适律，松弛了传统自适应控制方法中严格的持续激励条件.利用Lyapunov理论对闭环系统的稳定性进行了分析，并基于MATLAB/Simulink对比仿真结果验证了所提出控制方法的有效性.
A composite adaptive dynamic surface control method was proposed for high accuracy trajectory tracking of an electro-hydraulic servo system under interval excitation condition. By introducing the first-order command filters to process the virtual control signals during the controller designing process, the complicated calculation of the partial derivatives of the virtual control signals could be avoided. In order to realize the estimation and compensation of the unknown damping coefficient and unknown stiffness coefficient of the hydraulic system, a composite adaptive law was designed, and the stringent persistent excitation condition of the conventional adaptive control method was relaxed. The stability of the closed-loop system was analyzed by using Lyapunov theory, and the comparative simulation results based on MATLAB/Simulink have verified the effectiveness of the proposed control method.
［1］GUAN C, PAN S X. Nonlinear adaptive robust control of single-rod electro-hydraulic actuator with unknown nonlinear parameters ［J］. IEEE Transactions on Control Systems Technology, 2008, 16(3): 434-445.
［2］ZHENG J M, ZHAO S D, WEI S G. Application of self-tuning fuzzy PID controller for a SRM direct drive volume control hydraulic press ［J］. Control Engineering Practice, 2009, 17(12): 1398-1404.
［3］GUO Q Y, SHI G L, WANG D M, et al. Neural network-based adaptive composite dynamic surface control for electro-hydraulic system with very low velocity ［J］. Proceedings of the Institution of Mechanical Engineers, Part I: Journal of Systems and Control Engineering, 2017, 231(10): 867-880.
［4］徐张宝, 朱忠领, 马大为, 等. 考虑状态约束的液压系统自适应控制［J］. 西安交通大学学报, 2017, 51(1): 97-108.
XU Zhangbao, ZHU Zhongling, MA Dawei, et al. Adaptive control of hydraulic systems with state constrains ［J］. Journal of Xi’an Jiaotong University, 2017, 51(1): 97-108.
［5］YAO B, BU F P, REEDY J, et al. Adaptive robust motion control of single-rod hydraulic actuators: Theory and experiments ［J］. IEEE/ASME Transactions on Mechatronics, 2000, 5(1): 79-91.
［6］GUO Q, ZHANG Y, CELLER B G, et al. Backstepping control of electro-hydraulic system based on extended-state-observer with plant dynamics largely unknown ［J］. IEEE Transactions on Industrial Electronics, 2016, 63(11): 6909-6920.
［7］GUO Q, SUN P, YIN J M, et al. Parametric adaptive estimation and backstepping control of electro-hydraulic actuator with decayed memory filter ［J］. ISA Transactions, 2016, 62: 202-214.
［8］YAO J Y, DENG W X. Active Disturbance rejection adaptive control of hydraulic servo systems ［J］. IEEE Transactions on Industrial Electronics, 2017, 64(10): 8023-8032.
［9］熊义, 魏建华, 胡波, 等. 基于液压无源性理论的电液系统非线性鲁棒控制方法［J］. 农业机械学报, 2015, 46(11): 383-391.
XIONG Yi, WEI Jianhua, HU Bo, et al. Hydraulic passivity based nonlinear robust control for electrohydraulic system ［J］. Transactions of the Chinese Society for Agricultural Machinery, 2015, 46(11): 383-391.
［10］YANG X B, ZHENG X L, CHEN Y H. Position tracking control law for an electro-hydraulic servo system based on backstepping and extended differentiator ［J］. IEEE/ASME Transactions on Mechatronics, 2017, 23(1): 132-140.
［11］SWAROOP D, HEDRICK J K, YIP P P, et al. Dynamic surface control for a class of nonlinear systems ［J］. IEEE Transactions on Automatic Control, 2000, 45(10): 1893-1899.
［12］CHOWDHARY G, MUHLEGG M, JOHNSON E. Exponential parameter and tracking error convergence guarantees for adaptive controllers without persistency of excitation ［J］. International Journal of Control, 2014, 87(8): 1583-1603.
［13］KIM W, WON D, SHIN D, et al. Output feedback nonlinear control for electro-hydraulic systems ［J］. Mechatronics, 2012, 22(6): 766-777.
［14］YAO J Y, JIAO Z X, MA D W, et al. High-accuracy tracking control of hydraulic rotary actuators with modeling uncertainties ［J］. IEEE/ASME Transactions on Mechatronics, 2014, 19(2): 633-641.
［15］DONG W J, FARREL J A, POLYCARPOU M M, et al. Command filtered adaptive backstepping ［J］. IEEE Transactions on Control Systems Technology, 2012, 20(3): 566-580.
［16］YOO S J, PARK J B, CHOI Y H. Adaptive dynamic surface control for stabilization of parametric strict-feedback nonlinear systems with unknown time delays ［J］. IEEE Transactions on Automatic Control, 2007, 52(12): 2360-2365.
