电液比例系统变论域自适应模糊滑模控制  

Adaptive fuzzy sliding-mode control with variable universe for electro-hydraulic proportional system

作　　者：白寒[1] 管成[1] 冯培恩[1] 

机构地区：[1]浙江大学机械与能源工程学院,浙江杭州310027

出　　处：《电机与控制学报》2009年第5期728-733,共6页Electric Machines and Control

基　　金：浙江省重大科技攻关项目(2006C11148)

摘　　要：针对具有未知死区的电液比例系统,提出了一种带有死区补偿的变论域自适应模糊滑模控制方法。根据比例换向阀的死区特性,采用模糊逻辑系统设计死区预补偿器;将变论域的思想引入到自适应模糊滑模控制中,在线调节输入输出变量论域和隶属度函数,从而提高传统模糊滑模控制的精度;依据Lyapunov稳定性理论,构造变论域伸缩因子的自适应律,并对模糊逼近误差的上界进行实时估算,无需假设逼近误差上界已知。实验结果表明:采用变论域方法能有效地提高自适应模糊控制器的性能,在电液比例系统的位置跟踪控制中能克服系统固有的非线性特性、参数不确定性及外界干扰的影响,并且死区预补偿器消除了未知死区对跟踪精确度的影响,该方法具有响应快、精确度高、自适应鲁棒性强的特点。Based on the thought of variable universe, a novel adaptive fuzzy sliding - mode controller with variable universe was proposed for electro-hydraulic proportional system with unknown dead-zone. Considering the property of proportional valve dead-zone, a dead-zone compensator was designed using adaptive fuzzy logic. In order to improve the control performance, the universe of input variable and the membership functions of conclusion part in rules were adjusted on-line. According to Lyapunov stability theory, scaling factors adaptive update law was constructed. Moreover, to relax the requirement for the bound of approximation error, an error estimation method was developed to observe the bound of approximation error real-time. Experimental results show that variable universe method can effectively enhance the performance of adaptive fuzzy control. And when it is applied to a position tracking control of electro-hydraulic proportional system, this method can overcome the effect of inherent nonlinearity, parameter uncertainties and external disturbances. Since the influence of unknown dead-zone on tracking precision are eliminated by dead-zone compensator, the proposed scheme has features of fast response, high accuracy, strong robustness and good adaptive ability.

关 键 词：电液比例系统 变论域 自适应控制 模糊滑模控制 死区预补偿 

分 类 号：TP271[自动化与计算机技术—检测技术与自动化装置]