Isolation of Multiple Parametric Faults from a Hybrid Model

Isolation of Multiple Parametric Faults from a Hybrid Model 

Let m denote the number of component parameters. If the number m m oi parametric fault candidates exceeds the number n of sensors then a set of structured ARRs in which each ARR is sensitive to only one parameter cannot be achieved. That is, the FSM is not diagonal. Some rows in the FSM will have the same component fault signature so that some faults cannot be isolated. This result cannot be improved with regard to a further isolation of faults if the real system does not permit to add more sensors. That is, faults cannot be structurally isolated. 

The next sections first recall standard least square optimisation. Subsequently, this technique is applied to ARR residuals assuming that they can be obtained in closed symbolic form so that their expressions can be used in an objective function to be minimised. If unknowns cannot be eliminated from the sum of power variables at junctions to which a detector has been attached, then the time evolution of ARR residuals can be obtained by either computing ARRs as outputs of a 

Borutzky, Bond Graph Model-based Fault Diagnosis of Hybrid Systems, 

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