Abstract: Traditional system modeling rectuires the assumption that the model must be a complete one, according to this disadvantage, this paper proposed a method by synchronization components' model. The method synchronizes incomplete models to a larger one, to solve incomplete diagnosis caused by incomplete models. Optimizing dynamic diagnosis for discrete event systems,and with the idea of distributed system and the nature of Petri Nets, components can make diagnosis in an independent and parallel way, thus improve the rate of obtaining a diagnosis.

Key words: Discrete event system, Dynamic diagnosis, Petri net, Synchronization