| The industrial boiler is a system that is characterized as multi-inputs, multi-outputs, complex dynamic behaviors, and high control requirements. It is not controlled effectively enough by the traditional PID controller, but intelligence control theory, which has rapidly developed, provides a new way to solve such control problems. Considering the characteristics of the industrial boiler, an integral method which combines fuzzy control theory with PID is presented in this essay. The method can improve the control system's abilities of self-organization and self-study to meet the control requirements of such complex system from boiler production.In this essay, the characteristics of main vapor pressure and water level variation during the process of boiler production are analyzed and a computer digital simulation model of the control lee is established. By incorporating the process flow of boiler production, the essay presents a series- stage control system to form a combustion control system consisting of main vapor pressure, air-fuel rate and hearth negative pressure.It is proposed in this essay to make a fuzzy PID controller by combining fuzzy control with PID control, meanwhile, to improve the self adaptability by introducing parameter self-regulation function. It has been proved by digital simulation that static difference in control system is eliminated, and anti-disturbance ability is improved and that the control effect is satisfactory.It has been proved by digital comparison that establishing Takagi-Sugeno type FIS of better properties is practical by using study method of self adapting nervous network based on traditional FIS.The results of the computer digital simulation in this essay show that fuzzy PID control system has a better control effect than the traditional controller when the boiler of a complicated control system is to be controlled, which has the characteristics of nonlinear, changeable and big lag, and that the design of the control system is reasonable.
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