A FDI Procedure Based on Linearized Bilinear Mass and Heat Conservation Models

Abstract

Fault detection and isolation (FDI) for processes involving linear mass or energy conservation constraints is straightforward using standard statistical tools like GLR (generalized likelihood ratio). Non-linear relationships involving processes combining heat and material flows complicate FDI procedures. This paper proposes a method based on stationary bilinear mass and energy conservation models for the diagnosis of both sensor and process faults, making use of linear FDI tools. By locally linearizing the model equations, GLR detection and isolation tests can be applied to the residuals of parity relations. The method is illustrated for a simulated iron oxide pellet sintering furnace and its robustness is assessed with respect to the evaluation of the local operating level. Copyright ©2004 IFAC.