| As the energy crisis aggravates and the environment worsens,the significance of heating and energy saving becomes more and more significant.To retrofit the existing coal-fired heating boilers is the trend of the times.Boiler,known as the "industrial heart",whether it is production or industrial production of boilers are one of the important energy conversion equipment.However,compared with the boiler technology in developed countries,there is still a clear gap between the boiler technologies in China,mainly reflected in the main aspects of safety,environmental protection and energy consumption.If you want to fundamentally solve the problem,then the relevant technical transformation of the boiler,which is one of many current programs to spend the least one-way programs.This paper designed and implemented a set of boiler water temperature control system based on fuzzy PID,and joined the frequency conversion control system to realize the automatic control of boiler combustion process.Mainly to complete the following work:(1)The overall control scheme of heating boiler is designed and the hardware system design of boiler control system is completed.This system mainly studies and designs the control system of the boiler.First of all,understand the structure of the boiler,the working process and the combustion characteristics of the boiler.Finally,a feasible system control plan will be worked out.The control principle of heating boiler is briefly described.The control model of heating boiler system and the overall design of boiler control system are put forward.This article discusses the design goals,functional analysis and control schemes for a boiler control system.The upper computer in this system adopts high reliability industrial control computer to control and manage the same control system of the boiler.The lower computer adopts Siemens S7-300 programmable controller to realize the automatic control of the boiler combustion system and the pipe network system.The control Level and hardware reliability is greatly improved.(2)Complete fuzzy PID controller design and simulation to test its effectFirst introduced a variety of analog PID control and digital PID control,including incremental and position type.And introduced the development of fuzzy control and its principle and main components.Then the PID control and fuzzy control are combined to design a fuzzy PID control system which is in line with the temperature control system of the heating boiler water outlet to determine the parameters of the controller and its output lookup table.Finally,the simulation results show that the designed fuzzy PID controller The fuzzy system is well matched with the theoretical design,sensitive and reliable.(3)Complete the boiler control system software system designIn this paper,we first determine the selection of PLC and the selection of modules according to the requirements of system control;discuss the communication configuration between PLC and host computer,PLC and inverter,and design the communication protocol;design PLC control program,give the main program,basic functions Block and subroutine design flow chart and part of the ladder program.Host computer monitoring system to complete the monitoring and management of the entire system,the choice of WinCC to design,according to the requirements of users to complete the user interface and control procedures to achieve ultra-temperature overpressure alarm linkage and so on.Finally,the fuzzy control and the PID controller are combined to form a fuzzy PID controller,and finally the closed-loop control of the boiler effluent thermostatic system is realized.(4)System implementation and testingFinally,the whole system is implemented,and the corresponding tests are carried out in the industrial field.After testing and operating results show that using the fuzzy self-tuning PID controller we designed to control the outlet temperature,the system overshoot can be effectively reduced,Dynamic performance is very good. |
PDF Full Text Request