摘要
针对网络控制系统中存在的时变采样周期与时延,通过矩阵Jordan变换与分解,将采样周期和时延的不确定性转变为系统结构参数的不确定性,建立了离散时间凸多面体不确定系统模型。在此基础上,首先设计观测器,保证系统状态和故障估计收敛于实际值。接着,根据估计的故障,设计了主动动态输出反馈鲁棒容错控制器,给出了执行器发生故障时,系统能保持渐近稳定的充分条件。将控制器设计问题转化为以线性矩阵不等式形式为约束条件的凸优化问题,进而得出了最优H∞鲁棒容错控制器参数的具体表达式。数值仿真验证了提出的设计方法的有效性。
Robust fault tolerant control of networked control system (NCS) with variable sampling period and time delays was studied in this paper. First, a discrete - time model with parameter uncertainties lying inside a polytypic framework whose vertices were determined through the Real Jordan form approximation is proposed. Based on the model, an observer was proposed to estimate the fault and guar- antee the convergence speed of fault estimation. Furthermore, the robust active fault tolerant controller based on dynamic output feed- back was designed to guarantee the stability of the closed - loop system. A sufficient condition for the existence of controller to guarantee the system asymptotically stable is established in terms of linear matrix inequalities (LMIs). When the LMIs have an optimal solution, explicit expression of the desired optimal H∞ tolerant fault controller can be determined. Finally, numerical simulation is presented to il- lustrate the effectiveness of the proposed design techniques.
出处
《控制工程》
CSCD
北大核心
2013年第5期859-863,共5页
Control Engineering of China
基金
国家自然科学基金资助项目(60874053)
中南民族大学中央高校基本科研业务费专项资金资助项目(ZZQ10003)
关键词
网络控制系统
变采样周期
凸多面体不确定性
容错控制
线性矩阵不等式
networked control system
variable sampling period
convex polytopic uncertainty
fault tolerant control
linear matrixinequalities (LMIs)