ANALYTICAL REDUNDANCY METHODS IN FAULT DETECTION AND ISOLATION: Survey and Synthesis

Abstract

The best known residual generation methods in model based fault detection and isolation, including parity equations, diagnostic observers and Kalman filtering, are presented in a consistent framework. The discussion is organized along two residual enhancement concepts, namely structured and fixed direction residual sets. It is shown that, once the design objectives are selected, parity equation and observer based designs lead to equivalent residual generators. Robustness in the face of modelling errors is addressed and partially robust residual generator algorithms based on multiple model variants and on partial parameter insensitivity are reviewed.