Application of FDI Metrics to Detection and Isolation of Sensor Failures in Turbine Engines

This paper develops a framework for the design of Failure Detection and Isolation (FDI) algorithms. Rather than trying to apply "optimal" techniques in a top dowm manner, we take the view that system redundancies must be evaluated with respect to their ability to provide reliable FDI information. Previous work [1],[2] defined a useful context and several useful analytical results which provide a basis for the FDI design methodology developed here. A general decision structure which can take advantage of redundancy evaluation is presented and examples of typical design considerations are discussed. The operation of the decision structure is then demonstrated for a sensor FDI application involving the F-100 jet engine.