Graph Representation and Diagnosis for Multiunit Faults

A method using graph theory is proposed for the detection and the location of a multiunit fault in a system. The method requires only a slight increase in the number of internal monitoring terminals over the number required for the 1-unit fault diagnosis. A graph representation of a system initially leads to a rectangular diagnostic matrix. An algorithm is developed for constructing a square reachability matrix from the diagnostic matrix. A graph derived from the reachability matrix permits diagnosis of multiunit faults.