Design of Norm Based Fault Detection and Isolation LPV Filters

Abstract

This chapter investigates the design of robust fault detection and isolation (FDI) filters for linear parameter varying (LPV) systems. The goal is to obtain structured fault detection filters with enhanced fault transmission H_ gain and large H ∞ nuisance attenuation. Both the so-called polytopic and Linear Fractional Representation (LFR) approaches are considered.With respect to the polytopic approach, a sufficient condition is established to guarantee sensitivity performance of the residual signal vector to faults. Robustness constraints against model perturbations and disturbances are also taken into account in the design method. A key feature of the proposed method is that the residual structuring matrices are optimized as an integral part of the design, together with the dynamic part (i.e. the filter). The design problem is formulated as a convex optimization problem and solved using LMI (Linear Matrix Inequalities) techniques.With regards to the LFR approach, it is shown by means of the scaling matrices technique that the synthesis of the residual structuring and the filter state space matrices can be performed simultaneously using LMI techniques. Computational aspects are discussed and it is shown that the proposed solution is structurally well-defined. Academic examples are considered and discussed all along the chapter. A benchmark from the European FP7 funded ADDSAFE (Advanced Fault Diagnosis for Sustainable Flight Guidance and Control) project is finally considered to demonstrate the potential of the proposed approaches. The goal is to propose new fault detection and fault diagnosis techniques that could significantly help developing environmentally-friendlier aircraft. A LPV)model-based fault detection scheme is presented for robust and early detection of faults in aircraft control surfaces servo-loop. A complete MonteCarlo campaign from a ”high-fidelity” simulator provided by AIRBUS, demonstrates the potential of the proposed technique. It is shown that the proposed fault detection scheme can be embedded within the structure of in-service monitoring systems as a part of the Flight Control Computer (FCC) software.KeywordsFault DetectionFault DiagnosisFault Tolerant ControlLinear Parameter VaryRobust Fault DetectionThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.