Research And Design Of Control System For Central Heating And Heat Exchange Station

With the sustained growth of the national economy,China's urban construction is also in full swing.The increase of residential buildings makes the demand for urban winter heating increase.As an important part of central heating,the control effect of heat exchange station directly affects the heating experience of users.The temperature control of heat exchanger station mostly adopts manual regulation,which usually controls the temperature according to human experience,and its regulation often lags behind,which can not accurately reflect the relationship between supply and demand in heating process.When the heating temperature is higher than the demand,it is not conducive to energy saving;when the heating temperature is lower than the demand,the indoor temperature of users can not be guaranteed.In order to solve the above problems,this paper studies the heating theory of heat exchanger station,and completes the design of control system of heat exchanger station based on PLC and WinCC software.This paper focuses on the control system of heat exchange station in Jinta County residential district.The system is mainly composed of circulating pump system,supplementary pump system,pressure relief system and temperature control system.Combining with the local climate characteristics of Jinta County,a temperature control scheme suitable for this area is formulated.Temperature is an important control object of heat exchanger.In order to optimize its control effect,the heat exchange process of heat exchanger is analyzed based on thermodynamic theory,and the corresponding heat transfer model of the system is established.The operation characteristics of heat exchanger station are complex,and its temperature control system has the characteristics of time-varying.In view of the unsatisfactory control of time-varying system by conventional PID,the fuzzy control algorithm is used to optimize the algorithm of conventional PID controller.Fuzzy control realizes the control of time-varying system by modifying the parameters of PID on-line.In order to verify the superiority of the improved control algorithm,the control algorithm is simulated and compared with MATLAB simulation tool.In order to realize intelligent control and efficient management of heat exchange station system,local control system and upper monitoring system are designed respectively.Among them,the local control system mainly completes the tasks of PLC hardware selection,electrical cabinet design,field sensor selection and control program design.The upper monitoring system mainly completes the communication connectio n of GRM 530 remote module,the design of WinCC monitoring interface,and the design of WinCC database report forms.Finally,the field debugging of the whole system is completed.The system designed in this paper has been put into normal use.From the ove rall operation situation,the system has a good control effect on the heat exchange station.It not only realizes the requirement of heating on demand,but also achieves the purpose of saving energy.Therefore,this topic has theoretical research significa nce and practical application value.