An iterative approach to H−/H∞ fault detection for discrete-time systems in finite frequency domain

In this paper, an H
−
/H
∞
multi-objective fault detection observer design problem for linear discrete-time systems is studied. In order to reduce the conservativeness, the observer design problem is investigated in finite frequency range. Necessary and sufficient conditions for the existence of the observers to guarantee the fault sensitivity and disturbance robustness are presented. A new iterative linear matrix inequality (LMI) algorithm for the observer design is then proposed to obtain the solutions. Simulation results illustrate that the new method can effectively reduce the design conservativeness compared with the existing methods.