Auto-Coupling PID Control Method For Two Kinds Of Chemical Processes

Continuous stirred tank reactor(CSTR)and wastewater treatment process(WWTP)are widely used in chemical production field.The reaction temperature of CSTR system and the dissolved oxygen concentration in WWTP are the main parameters to measure the operation effect of the control system.With the gradual expansion of production scale and the increasing complexity of chemical production processes,the application scale of the above two types of chemical processes in industry is also increasing.Therefore,the study of CSTR reaction temperature control and WWTP dissolved oxygen concentration control has important theoretical significance and practical application value.Aiming at the objectives of CSTR reaction temperature control and WWTP dissolved oxygen concentration control,based on the analysis of static and dynamic characteristics of CSTR cooling system heat exchange process and various mechanisms involved in biochemical reactions in WWTP,this thesis aims to achieve the objectives of CSTR exothermic reaction stability and safety and WWTP effluent substrate concentration reaching the standard,and to improve the control effect and economic benefit of CSTR reaction temperature and WWTP dissolved oxygen concentration control,Optimize economic indicators and improve system control performance while achieving rapid response.In this thesis,the auto coupling proportional integral differential(ACPID)control theory is used to realize the control of the above two kinds of chemical processes.According to the ACPID control theory,the internal dynamic parameters of two kinds of complex chemical processes are defined as "total disturbance",and the two kinds of complex chemical processes are mapped to linear disturbance processes with unified form.The advanced ACPID control method is used to obtain good dynamic quality and stable performance,which reflects the idea of "unity" control theory;In the analysis of anti-disturbance robustness of ACPID control theory,it is proved that the upper bound of steady-state error is inversely proportional to the square of "peed factor",which has a scientific theoretical guidance for improving steady-state control accuracy and anti-disturbance ability.Through theoretical analysis and simulation experiments,this thesis shows that the ACPID control method in the above two types of chemical process control shows that the control time is short,there is no overshoot,and it can better realize the high-quality and high-efficiency operation in the actual production process.It can improve the control accuracy and anti-disturbance robustness of the controlled quantities in the two types of chemical processes,prevent the parameters from getting out of control in the chemical process It has important theoretical significance and practical application value to ensure production safety,improve production efficiency and reduce production costs.