The Design Of Sodium Chloride Floatation Reagent Production Control System Based On DeviceNet

Sodium chloride flotation engineering is one of the development of western China "ten great projects" potash project components.their potash production line adopts suspension the process,it has advantages of good product quality,high utilization rate of raw materials,but it needs more stringent production process parameters.Therefore,the system needs higher quality equipments and more advanced methods to control the production process.In this paper,analyses the characteristics,communication mode and principle of DeviceNet fieldbus technology is given.According to the study of the production process,A dual CPU redundancy control system based on Rockwell PLC and three-layer networks is designed.The system builds on the Rockwell three-layer nets architecture.In the control layer,Rockwell ControlLogix platform is the cardinal controller,the control programs are compiled in RSLogix5000 software;in the device layer,the centralized control of Low-voltage electrical devices uses the Motor Control Center(MCC).VFD,E3 Plus Relay and SMC soft starter are the three kinds of control units;PC monitoring system is designed in the FactoryTalk View SE configuration software in the information layer.The control strategies of the reaction kettle temperature are researched deeply.After simulative researches about PID control strategy which is adopted in the site,the deficiencies of PID control strategies are obtained and an improved project,neural network predictive control based on BP algorithm is proposed.The simulation results certify that the NPC strategy can solve the problems of delay part,modeling imprecision and vulnerability,it also can get better dynamic characteristic and robustness.The NPC strategy offers a new project for further optimization of the system.The trial operation results show that the control system has high reliability,strong stability,accurate control effect and good openness as well as extensibility,which can fulfill the control demands of the industrial site.It has a certain value to promote.