Application And Design Of Gas Boiler Combustion Controller

The gas boiler is a kind of highly efficient energy conversion equipment,has extensive use in industry and life,and it is bound to replace the coal-fired boiler.This not only because of the superior performance of gas boiler,more to the point is that its excellent environmental protection.Early coal-fired boiler in the boiler industry proportion is very high,with environment for the economic benefits,also caused serious damages to the environment.In recent years,the country’s development has attracted worldwide attention,growing environmental problems,so the state policies to make up,the "coal to gas" plans to gradually expand in the major cities;t is to use high quality environmental protection of the natural gas of gas boiler to replace inefficient pollution of coal-fired boiler.This article is to gas boiler as the carrier,and design a relatively overall control system.First,this paper studies the running mechanism of the gas boiler.Gas boiler is to burn a certain proportion of mixed gas and air,produce heat.Water in the boiler absorbs the heat to reach a certain temperature,and the water is conveyed to customer.In this paper,the purpose of design is to ensure that the air-fuel ratio keep a constant,in order to be environmental protection,energy saving and efficient.So,choose one of the most appropriate algorithms as its control core.And then,on the basis of running mechanism,the structure of control system is made detailed analysis,and designed a system structure of two input two outputs.With water temperature and flue oxygen respectively as control object,the air-fuel ratio of the two ties,MATLAB/SIMULINK simulation model is set.Industry widely used conventional PID algorithm and intelligent fuzzy self-tuning PID algorithm respectively as its control algorithm,has carried on the comparative analysis.Analysis shows that the fuzzy self-tuning PID algorithm in the overshoot,adjustment time,steady-state error and interference performance has obvious advantages than conventional PID.Secondly,with the help of a Samsung S3C2440 microprocessor as the core of TQ2440 development board,gas boiler combustion controller and peripheral circuit is designed.In addition to the minimum system,power supply circuit,reset circuit indispensable is provided by the development board,the D/I、A/D、D/A、relay drive、LCD interface、key、LED circuit are designed in this paper.And use Altium Designer 10 to complete its principle diagram and PCB design.Finally,with intelligent trend,the design of the software transplant the real-time multitasking operating system uC/OS-Ⅱ and uC/GUI graphical user interface.Real-time multitasking operating system uC/OS-Ⅱ transplantation not only improves the reliability of the control system,but also divides the priority task,make the programming more organized,and facilitate maintenance and transplantation.The transplantation of uC/GUI graphical user interface simplifies the underlying graphics LCD driver writing,directly call uC/GUI rich function library,enable to draw the elegant interface,greatly enhance the efficiency.