Prognosis of Failure Events Based on Labeled Temporal Petri Nets
Redouane Kanazy, Samir Chafik, Éric Niel · Advances in Science Technology and Engineering Systems Journal · 2020
To reduce the risk of accidental system shutdowns, we propose to control system developers (supervisor, SCADA) a prediction tool to determine the occurrence date of an imminent failure event.The existing approaches report the rate of occurrence of a future failure event (stochastic method), but do not provide an estimation date of its occurrence.The date estimation allows to define the system repair date before a failure occurs.Thus, provide visibility into the future evolution of the system.The approach consists in modelling the operating modes of the system (nominal, degraded, failed); the goal is to follow the evolution of the system to detect its degradation (switching from nominal to degraded mode).When degradation is reported, a prognoser is generated to identify all possible sequences and more precisely those ending with a failure event.then it checks among the sequences (with failure event) which ones are prognosable.The last step of the approach is carried out in two parts: the first part consists in calculating the execution time of the socalled prognosable sequences (by optimizing the number of possible states and resolving an inequalities system).The second part makes it possible to find the minimum execution (the earliest occurrence of a failure event).