Vector based fault isolation in closed-loop systems.

Isolation of parametric faults in closed-loop MIMO systems is considered in this paper. A double residual generator is applied for the isolation.
First, it is shown that there is a linear dependency of the single parametric faults and the residual vector. Based on this linear dependency together with the dual residual vector, residual output directions are calculated for each parametric fault. These output directions for the residuals are independent of the value of the single faults. The fault isolation is then done by comparing the residual vector with the calculated output vectors for the different faults. To isolate a fault, the calculated output vector for the given fault and the residual vector need to be parallel. The scalar vector product between the vectors is applied as a simple test method for fault isolation.