Admissibility Analysis of a Sampled‐Data Singular System Based on the Input Delay Approach

This study investigates the sampled‐data admissibility problem for a singular system. The objective of this paper is to design a sampled‐data controller to ensure the admissibility of a singular system and to construct an appropriate Lyapunov–Krasovskii functional (LKF) to get less conservative results for the sampled‐data singular system. To accomplish these objectives, the system is converted into a time‐delay system by the input delay approach firstly, and both lower and upper bounds of the delay are considered. Secondly, by introducing a suitable LKF, the admissibility criteria are obtained. Then, when estimating the derivative of the LKF, a relaxation variable is introduced by the method of reciprocally convex inequality, and it is proved that the conservatism is reduced. Finally, two numerical examples are given to prove that the designed sampled‐data controller can ensure the states of the systems under the influence of external interference.