Research On Main Steam Pressure Control Of CFB Boiler

Circulating fluidized bed boiler (CFBB) control strategies based on classical control theory or modern control theory all need exact mathematical models of controlled objects. It is very difficult to establish the exact mathematical models of controlled objects because the combustion system of circulating fluidized bed boiler is an object that has many features: distributed parameters, nonlinear, time-varying and a lot of tightly coupled variables. Dissertation is dedicated to solve the practical control problems in power plant on the basis of theoretical research. Under the existence of the dynamics characterized by non-linear, significant delay and time varying, the work strives to deal with the problems of significant delay objects control in large power plants, which have puzzled the power plants for long time. This text passes the analytical research CFBB combustion system characteristic, designed control system of power plant and bus system power plant. The improved Smith control strategies mentioned above based on Internal Model Control and robust control, have been applied to pressure control system with significant delay and time varying. The results indicate that the control quality, the speediness, the robustness are all superior. It is advantageous to be used in the practical control system.