ROOM 3   PLENARY TALK   Professor Antonio Ramírez Treviño, PhD  Title  Fault Diagnosis in Petri Nets
Channel: Cinvestav - Ingeniería Eléctrica
Date: 2022-11-15

In this problem both, the model and set of potential system faults are known, and the actual occurrence of a fault must be determined from the system outputs during its evolution.

First, we review the basic concepts about fault diagnosis and Petri nets (PN). Afterwards, we present sufficient structural conditions to guarantee the non-concurrent diagnosability property in a PN structure. In this case, the non-existence of infinite length indistinguishable output cycles is enough to determine that faults are diagnosable; from the PN structure perspective, it is equivalent to the non-existence of T-semiflows that could be fired with independence of the fault occurrence. Later, the concurrent diagnosability is presented to deal with system exhibiting concurrence.

Subsequently, the diagnosability problem in Timed Continuous Petri net (TCPN) is also addressed from a structural perspective. Since TCPNs are positive affine switched linear systems, the diagnosability is more complex to analyze, and reported results are based on the analysis of the paths from potential faults to sensors. When the transfer functions from potential faults to the outputs are all different from each other, then every fault is diagnosable. Then, a brief review of the results about fault diagnosis in linear systems using unobservability spaces is presented, establishing

bridges between the diagnosis in linear systems and Petri nets. Finally, the distributed diagnosis problem, using the notion of quotient Petri net, is addressed. The advantage of this approach is that diagnosability can be achieved efficiently, because T-semiflows that could be fired with independence of fault occurrence are efficiently obtained.