Design And Application Of Control System For Gas Fired Hot Water Boiler

With increased awareness of environmental protection,Gas boilers has showed the advantages of low energy consumption,low pollution and high efficiency compared to traditional coal-fired boilers.It will also gradually become the preferred choice of heating systems in the new ear.This thesis designs a gas boiler combustion control system based on a clean energy transformation project of a coal-water slurry boiler for a housing estate by removing the existing coal-fired boilers and building three new gas-fired boilers.A fuzzy self-tuning PID algorithm is proposed by combining process control,instrumentation testing and computer technology follow the principles of high efficiency,operability and maximising economic efficiency.The main contents are as follows:(1)A brief overview of the project is given,outlining the basic control requirements and process principles of the system,analyzing the various components of the system and drawing a block diagram of each subsystem.(2)The overall system solution design is completed,including system hardware architecture and software architecture design.(3)A fuzzy self-tuning PID controller is designed by determining the affiliation function and fuzzy control rule base,and the system model is established in MATLAB by using the system identification toolbox.The feasibility and advantages of the fuzzy self-tuning PID algorithm are verified by comparing the simulation analysis of the identification model with conventional PID in Simulink.(4)The S7-200 SMART is used as the core executive layer component.The hardware of the relevant detection components is selected,the PLC program is designed and a portion of electrical diagrams are drawn.(5)A man-machine monitoring interface including user login,main interface monitoring,pump control,parameter setting,alarm recording and other functions is developed in Siemens Win CC configuration software platform.(6)The sources of disturbances at the site are analyzed and the measures of resisting disturbances are established.The power-up and power-down checks and comprehensive commissioning of the equipment are introduced,and common problems and precautions in the project are described.The gas boiler control system designed in this thesis is easy to operate,fully functional and effective,easy for staff to master with a terse and friendly interface,which can meet the basic requirements of the project transformation and environmental protection and ensure long-term operation,and has reference value for the design and commissioning of control systems for similar projects in the future.