Modified Repetitive Control Design for Nonlinear Systems With Time Delay Based on T–S Fuzzy Model
针对一类连续时间非线性时滞系统，基于T-S模糊模型设计了一种改进重复控制器，使系统输出能跟踪任意周期参考信号并抑制周期扰动，通过线性矩阵不等式保证鲁棒稳定性。
In this paper, based on the Takagi-Sugeno fuzzy model approach, a novel output feedback control strategy is developed for a class of continuous-time nonlinear time delay systems via modified repetitive control scheme. The main objective of this paper is to design a fuzzy rule-based modified repetitive controller such that the system output can track any given periodic reference signal even in the presence of periodic disturbances. For this purpose, by employing fuzzy-dependent Lyapunov-Krasovskii functional together with the free-weighting matrix technique, a new set of sufficient conditions is presented in terms of linear matrix inequalities to guarantee the robust stability of the resulting closed-loop system. Based on these conditions and using internal model principle, it is shown that the system output tracks the given reference input within the desired error. Finally, two application-oriented examples are presented to validate the obtained theoretical results in which the proposed control design scheme gives better performance over the existing control scheme.