Model Analysis And Optimization Study On Combustion Control System Of CFB Unit

Circulating fluidized bed boiler as a new type of clean coal combustion technology,has been applied in the each capacity level of power plant in our country.This technique with the advantages of advantageous in the burning of inferior coal in our country electric power industry proportion of larger and larger.But low input ration automatic control system of problems followed.Mainly from two aspects of reasons for this: on the one hand because of CFB boiler,it is necessary to study the mechanism of internal combustion,on the other hand is a mature of the pulverized coal furnace automatic control system can't completely suitable for CFB boiler.With the large-scale development trend of circulating fluidized bed boiler,the combustion system of the internal mechanism of research also gradually in-depth.Thin,dense phase area based on CFB boiler energy balance and mass balance equation,the bed is obtained according to the on-site data identification,moderate and the mathematical model of main steam pressure laid the foundation for follow-up study.First of all,based on the coupling between the bed and main steam pressure,using the feedforward compensation method and series compensation method two decoupling algorithm to realize decoupling.By decoupling got to the coal bed temperature control,once the single variable air volume control of main steam pressure control system.Then,this paper established the model of parameter identification,the final obtained under disturbances to the coal bed,the mathematical model of temperature.Respectively using PID control,fuzzy control,fuzzy adaptive PID control for the system are simulated.Through comparison and analysis of the simulation curve,it is concluded that intelligent algorithm better than the traditional control algorithm in the control on the quality.Finally,the article of CFB boiler combustion optimization of the actual project in a power plant,of bed temperature control system,to the coal quantity control system and limestone quantity optimization design was carried out on the control system,have complete DCS control system model and optimization control model two kinds of control mode.The experimental results show that the optimized system control quality had the very big enhancement,and can be done with the original DCS system tracking,the undisturbed switch to each other.