This paper investigates the problem of robust fault detection observer design for nonlinear Takagi–Sugeno models with unmeasurable premise variables subject to sensor faults and unknown bounded disturbance. The main idea is to synthesize a robust fault detection observer by means of a mixed H =H1 performance index. The considered observer is used to estimate jointly states and faults. Using the...

In paper [1] a new robust decoupling state observer including an extra non-linear term has been proposed by Gu and Poon. This extra term is used to overcome the difficulty due to the unstructured parameter perturbation. It was highlighted that the nonlinear observer scheme requires the solution to a quadratic matrix inequality which is not straightforward. This inequality was rewritten as a qua...

We extend existing theory on robust nonlinear observer design to the class of nonlinear Lipschitz systems where the systems are subject to sensor faults and disturbances. The designed observer is used for robust reconstruction of fault signals. Allowing bounded unknown disturbances to model system uncertainties, it is shown that by adjusting a design parameter we can trade off between fault rec...

SUMMARY This paper proposes a robust state observer for multi-input multi-output LTI systems. Unknown inputs of polynomial form and high-frequency measurement noises are considered in the system model. The unknown inputs and the noises are not in the same form. Multiple integra-tions of both the observer error signal and the measurement output are used for the observer design. The existence con...

In this paper, the sliding mode observers design techniques for MIMO and as a simple example for SISO systems are systematically advanced as a first purpose. Design parameters are selected such that on the defined switching surface always is generated asymptotically stable sliding mode. Moreover, observer state error dynamics is globally robustly asymptotically stable. Then, advanced design tec...

In this paper, the design of an interval observer with an adaptive dynamical gain is presented. The observer is formulated in the framework of robust state estimation of uncertain dynamical systems, where an interval that encloses the unknown state variables is provided. For a specific type of interval observer design, an optimal gain could provide the narrowest interval. Since this gain depend...

This paper addresses the design of observer-controllers that provide “robust” output regulation. By this we mean that regulation is achieved without knowledge of how the disturbances actually enter the system. While it would seem that this problem has already been settled by the internal model principle (IMP), it turns out that in its original formulation, the IMP is most directly applicable to...

The design of state observer for a linear discrete or continuous time uncertain system based on circularly regional pole assignment is studied. Taking use of algebraic Riccati equations and linear matrix inequalities, necessary and sufficient conditions for the existence of the state observer based on circularly regional pole assignment is proposed and the formulation of the gain matrix of the ...

This paper addresses parameter and state estimation problem in the presence of the perturbation of observer gain bounded input disturbances for the Lipschitz systems that are linear in unknown parameters and nonlinear in states. A new nonlinear adaptive resilient observer is designed, and its stability conditions based on Lyapunov technique are derived. The gain for this observer is derived sys...

Abstract Power systems are subject to undesirable small oscillations that might grow to cause system shutdown and consequently great loss of national economy. The present manuscript proposes two designs for observer-based robust power system stabilizer (PSS) using Linear Matrix Inequality (LMI) approach to damp such oscillations. A model to describe power system dynamics for different loads is ...