LMI approach to mixed H_/H ∞ fault detection observer design

Abstract

To investigate the robust fault detection (RFD) observer design for linear uncertain systems, the H t_ index and H ∞ norm are used to describe this observer design as optimization problems. Conditions for the existence of such a fault detection observer are given in terms of matrix inequalities. The solution is obtained by new iterative linear matrix inequality (ILMI) algorithms. The RFD observer design over finite frequency range in which D f does not have full column rank for a system is also considered. Numerical example demonstrates that the designed fault detection observer has high sensitivity to the fault and strong robustness to the unknown input.