Against such characteristics as relevance

uncertainty and time delay in combustion system

the association of factors influencing the safety and economy of boiler operation was analyzed.Therefore

a distributed model consisting of three related subsystems such as steam pressure

oxygen content in flue gas and furnace pressure was established.Predictive control was conducted on this model

in which the prediction and control only depend on partial design

because when a fault occurred on the local function

the global control performance would not be reduced a lot

it would be recovered itself after trouble clearing.The simulation results showed that

this predictive control method had good precision

and can return to steady state soon after being disturbed.So it has strong robustness.The practical application showed that

the predictive control method improved the combustion greatly and can save nearly 4% of the coal.