Research And Application Of Heating Pulverized Coal Boiler Combustion Control System

Boiler combustion control is of great significance for heating system in heating regulation, boiler's safety, energy saving and high efficient operation. Boiler combustion system is a complex time-varying dynamic process, which has highly nonlinear, tightly coupled, long delay and strong interference characteristics. The traditional control algorithms are difficult to obtain the ideal control effects and higher operation rates. Therefore, it is a hot topic on the current research that how to use some recent advanced strategies for effective control to the boiler combustion ensures the heating supplies of boiler's heating output and heat-network's changing loads and ensures boiler's safety, economy and stable operation.Based on the analysis of dynamic characteristics of boiler combustion system, the paper deeply studies the parameters relationship of boiler combustion system. The heating boiler combustion control is reduced to control of the coal supply of boiler, secondary air volume and importing air volume. In the realization of boiler combustion control system, the paper, combining the characteristics of generalized predictive control and fuzzy control, puts forth the cascade control system that is made up of the generalized predictive control and PID control and to make the furnace temperature as control objectives for the secondary air supply and to implement self-optimizing fuzzy control to the oxy-acetylene ratio. Besides, the thesis introduces strategies of using the fuzzy control in large deviation and employing the PI control in small deviation to the air volume controlThe subject derived from a project of China Coal Research Institute in Da Tong city of Shan Xi province, prompting the use of pulverized Coal Boiler. When furnishing auto control system for Boiler Heating system, systematically studying the traits of boiler combustion control. On the wind and coal proportion self-optimizing control of secondary wind motor, this article improves the using of self-optimizing control, which has heavy impact on the negative pressure of boiler through controlling secondary wind motor. Based on the real time frequency-converting value, improved fuzzy self-optimizing control limit its output by using the frame intensity as condition of start and stop to the original routine. From the frame monitor in the control room, it is obvious that the boiler combustion frame becomes bright and stable using this control strategy.In this project, Schneider QUANTUM PLC is used in coal powder boiler heating system to achieve the overall control of automatic coal delivery, combustion, coal warehouse temperature control, water cycle control, replenishment control, dust catch, boiler ignition.