A Petri-Net Based Characteristic State Supervisor Of Chemical Batch Process

Monitoring in industrial process is an important instrument and key technology in ensuring running stability and reliability of manufacture system, and in improving products' quality and increasing profits. Batch process monitoring with Petri net is a comparatively active research field at present. This paper deeply researches the problems of monitor in the batch process based on timed Petri net and hybrid Petri net, which is followed by a sulfuration accelerant M produce process experiment illustrated as an example to establish a process monitor simulation system of batch process based on high Petri net, and eventually validates the methods of modeling and simulation.The first part of this paper introduces the fundamental concepts of timed Petri net and fuzzy Petri net, and simulates some industry process based on Matlab. In the second part, a new concept about the development and implementation of feature- and model-based monitoring methods using high-level Petri net specifications and based on hybrid specifications in batch process is presented which establishs a new Petri-net based characteristic state supervisor with a hierarchy construction. The characteristic state supervisor is composed of real-time data processing module, expert supervisor module and characteristic state supervisor module with two layers of Petri net. The supervisor can monitor the discrete magnitude and the continuous magnitude using the interaction of the three modules. The lower layer of the two Petri net extracts the discrete state in the controlled process using hybrid Petri net while the higher layer describes characteristic state's evolution rule in the batch process. The expert supervisor model gives the monitor information when some unusual circumstance occurs. Beyond the theory research, the object of a sulfuration accelerant M produce process experiment is set to detailed elaborate the design of supervisor and it is simulated in matlab, the the discussion explains it can provide some useful tools in supervisor model based on Petri net.The analysis in this paper indicates that the modeling and simulation method about monitoring research based on timed Petri net and hybrid Petri net in the batch process points to a good direction for futher reasearch. It makes it possible to monitor and analyze the batch process based on Petri net. An expectation is that this approach will be widely used in application of batch chemical process.