INFORMATION CRITERIA FOR RESIDUAL GENERATION AND FAULT-DETECTION AND ISOLATION

Using an information point of view, we discuss deterministic versus st ochastic tools for residual generation and evaluation for fault detect ion and isolation (FDI) in linear time-invariant (LTI) state-space sys tems. In both types of approaches to off-line FDI, residual generation can be viewed as the design of a linear transformation of a Gaussian vector (the finite-window input-adjusted observations). Several statis tical isolation methods are revisited, using both a linear-transform f ormulation and the information content of the corresponding residuals. We formally state several multiple-fault cases, with or without causa lity assumptions, and discuss an optimality criterion for the most gen eral one. New information criteria are proposed for investigating the residual optimization problem. (C) 1997 Elsevier Science Ltd.