H fault estimation problem for a class of time-delay systems using a new state transformation
Abstract
In this paper, we study the problem of H 1 fault estimation for a class of time-delay systems with unknown inputs. First, a new state transformation is derived to transform the system into new coordinates where the delay term associated with the state vector is injected into the system output and input. Then, an observer-based H 1 fault estimator with input and output injections is proposed for fault estimation. Based on the Generalized Kalman-Yakubovich-Popov Lemma, sufficient conditions on the existence of the H 1 fault estimator are derived and a solution to the observer gain matrices is obtained by solving a set of linear matrix inequalities. A numerical example is given to illustrate the effectiveness of the proposed method.