On the Control Methods of Atmospheric Fluidized Bed Boilers for Power Generation

This paper deals with the state of the art of controlling atmospheric fluidized bed steam generators. The emphasis has been placed on multivariable control to provide optimum performance within environmental constraints. A general multivariable model structure is used. The specific model parameters are determined from actual input-output relations (process reactions). Control and optimization methods for commercially implementable controls are presented. The usage of feedback, feed-forward, cascade, and decoupling controls is discussed for the general model. A comparison is made between the proposed controls and those used for conventional boilers to identify areas where particular caution must be exercised in dealing with atmospheric fluidized bed boilers. The implementation and computational capabilities including the current challenges and the needs for further work are presented.