*Article* **Fault Detection for Interval Type-2 T-S Fuzzy Networked Systems via Event-Triggered Control**

**Zhongda Lu 1,2, Chunda Zhang 1, Fengxia Xu 1,2, Zifei Wang 1 and Lijing Wang 1,2,3,\***


**Abstract:** This paper investigates the event-triggered fault diagnosis (FD) problem for interval type-2 (IT2) Takagi–Sugeno (T-S) fuzzy networked systems. Firstly, an FD fuzzy filter is proposed by using IT2 T-S fuzzy theory to generate a residual signal. This means that the FD filter premise variable needs to not be identical to the nonlinear networked systems (NNSs). The evaluation functions are referenced to determine the occurrence of system faults. Secondly, under the eventtriggered mechanism, a fault residual system (FRS) is established with parameter uncertainty, external disturbance and time delay, which can reduce signal transmission and communication pressure. Thirdly, the progressive stability of the fault residual system is guaranteed by using the Lyapunov theory. For the energy bounded condition of external noise interference, the performance criterion is established using linear matrix inequalities. The matrix parameters of the target FD filter are obtained by the convex optimization method. A less conservative fault diagnosis method can be obtained. Finally, the simulation example is provided to illustrate the effectiveness and the practicalities of the proposed theoretical method.

**Keywords:** fault diagnosis; event-triggered control; interval type-2 Takagi–Sugeno fuzzy model; nonlinear networked systems; filter
