Fault Diagnosis in Di erential Algebraic SystemsbyMarios

A large class of engineering systems are modeled by coupled Diierential and Algebraic Equations (DAEs). Due to the singular nature of the algebraic equations, DAE systems do not satisfy the standard state-space description and require special techniques. So far, the literature has concentrated mostly on the numerical analysis and control aspects of DAE systems. This paper investigates the problem of health monitoring and fault diagnosis in DAE systems. The main objective is the development of numerically feasible on-line approximation schemes for robust and stable fault diagnosis of DAE systems. The proposed fault diagnosis architecture monitors the physical system for any oo-nominal behavior using nonlinear modeling techniques and learning algorithms. The on-line approximation scheme is utilized not only to detect but also to provide a model of any faults, which is useful for fault isolation, identiication and accommodation purposes. The stability and robustness properties of the fault diagnosis scheme are investigated. A simulation example illustrating the ability of the proposed fault diagnosis architecture to detect faults in a chemical reactive ash is presented.