Ding, Y.; Müller, J. R.:
Analysis of the Unavailability of Instrumentation and Control Functions Important to Safety for a Nuclear Power Plant.
Proceedings of the 2nd IFAC Workshop on Dependable Control of Discrete Systems (DCDS), S. 179-184, Bari, Italy, June 2009.


Abstract: To optimize the proof intervall of a reactor limitation system the unavailability analysis has been carried out. First of all the relevant operation and failure behavior of the 2-out-of-4 I&C system with high redundancy has been described by an analytical model. The maximal, minimal and average values of the unavailability are calculated. After that a Petri net model for describing the system behavior has been developed. The results gathered by Petri net simulation are quite comparable with the analytical calculation. Keywords: Nuklear Power Plant, Reactor Limitation Device, Periodical Inspection, Unavailability Analysis, Petri Nets