Using of supervisory control theory in emergency shout down control system of an off-shore gas platform
Abstract
This paper focuses on modeling of emergency shut-down control system in an off-shore gas platform using petri net. Considering the nature of the safety control system in industries, it can be considered as a discrete event system. In this regard, first the equipments under emergency shutdown system along with the rules that govern how they act are modeled. Then, the local shut down in all unit separately , after that, process shut down which rules the performance of process unit equipment in emergency situation, in the next step, high level emergency shutdown(level ) and the platform emergency shut down as a hierarchical modeling system are modeled . Finally by combining the models, the final structure implementable on programmable logical controller was modeled by Snoopy software. The full model contains details of all units and criteria governing them, we suffice to mention excerpts of the entire designed model.