Fault Detection and Isolation of Control Systems Based on Geometric Approach

Optimal fault detection and isolation filter design based on Geometric Approach are proposed for control systems with disturbances.By using the unobservability subspace concept,the smallest unobservability subspace is constructed to describe the fault characteristics and realize faults decoupling. The residual is established with feasible solution of fault detection and isolation filter,and it is only sensitive to the detected fault.Afterwards,the influence of the disturbance to the residual is reduced with H∞ technique,which improves the sensitivities of residual to fault signal and the robustness to disturbance as well.The optimal solution of residual set is described with LMI.Finally,simulation results are presented to show the effectiveness of the proposed approach.