Dynamic Observer and Disturbance Observer Based Fault Estimation and Fault-Tolerant Control of Switched Fuzzy Stochastic Systems

In this paper, fault estimation and fault-tolerant control of switched fuzzy systems with fault, disturbance and stochastic noise are studied. Considering the presence of actuator fault in this system. When the fault size changes frequently, the classical proportional-integral observer is not easy to obtain accurate estimation results. Therefore, we design a dynamic observer, and introduce the derivative of output feedback to improve the estimation performance. At the same time, the disturbance observer is added, which can simultaneously estimate the system state, actuator fault and disturbance. Based on the estimated information, a fault-tolerant controller is constructed. Finally, the linear matrix inequality conditions have been obtained, which make the whole system is mean-square exponentially stable with root-mean-square performance.