Fault Estimation for a Class of Discrete-Time Nonlinear Systems With Adaptive Fuzzy Observer
针对一类离散时间非线性系统，提出一种自适应模糊观测器方法，用于估计系统故障，并通过电路系统示例验证了有效性。
This article develops a fault-estimation (FE) method for a class of discrete-time nonlinear systems subject to unknown nonlinearities, external disturbances, and actuator faults. In this work, an adaptive fuzzy observer is first designed for discrete-time systems to eliminate the effects of nonlinearities on the FE performance. Subsequently, the rank constraints of disturbance coefficient matrices in traditional discrete-time FE results are relaxed by decomposing the disturbances into virtual perturbations and states. Furthermore, an adaptive mechanism is introduced to reconstruct the states and faults without prior knowledge of unknown perturbations. Finally, the effectiveness of the proposed adaptive fuzzy FE method is validated through a circuit system example.