Design Method of Control System for HTGR Fuel Handling Process with Control Petri Net

As a complex mechanical system,the fuel handling system (FHS) of pebblebed high temperature gas cooled reactor (HTGR) is with the features of complicated structure,numerous control devices and strict working scheduling.It is very important to precisely describe the function of FHS and effectively design its control system.A design method of control system based on control Petri net (CPN) is introduced in this paper.By associating outputs and operations with places,associating inputs and conditions with transitions,and introducing macro-places and macro-actions,the CPN realizes hierarchy design of complex control system.Based on the analysis of basic functions and working flow of FHS,its control system is described and designed by CPN.According to the firing regulation of transition,the designed CPN can be easily converted into LAD program of PLC,which can be implemented on the FHS simulating control testbed.Application illuminates that proposed method has the advantages of clear design structure,exact description power and effective design ability of control program,which can meet the requirements of FHS control system design.