模糊非脆弱动态输出反馈H_∞控制器设计

Non-fragile dynamic output-feedback H-infinity control for fuzzy discrete-time systems

本文考虑受有限字长影响的离散时间模糊系统的非脆弱H∞控制问题.假定所设计的控制器具有加性区间型增益变量,该增益变量反映了控制器数字执行过程中有限字长的影响.区间型增益变量导致控制器设计具有数值计算问题,而模糊性质的引入进一步增加了控制器设计的复杂性,使问题变得更具有挑战性.本文采用结构的顶点分离器方法来解决数值计算问题,从而给出一个基于线性矩阵不等式的模糊非脆弱H∞控制器设计的两步算法.该设计结果保证闭环系统渐进稳定并具有指定的H∞性能指标.最后给出一个数值例子验证所提出方法的有效性.

We investigate the design of a non-fragile dynamic output feedback H-infinity controller with finite word length （FWI） for fuzzy linear discrete-time systems. It is assumed that this controller is with an interval additive gain variable which reflects the effect of the word length on the numerical execution. The introduction of the fuzzy property increases the complexity of the controller design, making the problem more challenging. To deal with the numerical computation problem, we employ a structural vertex separator, and develop a LMI-based 2-step method for designing the fuzzy non-fragile H-infinity controller. This design guarantees the asymptotic stability of the closed-loop system with desired H-infinity performances. A comparison between the proposed method and the existing method in the design of the fuzzy non-fragile H-infinity controller is provided, and a numerical example is given to validate the analytical results.