Hierarchical and heuristical fuzzy model based control of drum-boiler power plant

A fuzzy model based control methodology is proposed for controlling the steam generation in a drum-boiler power plant. For such a system, a controller that preserves stability and performance for a wide range of operating conditions and disturbances is especially desirable. The control design is based on a Takagi-Sugeno fuzzy dynamic model (1985) which is a fuzzy aggregation of a set of linear models defined at various operating load conditions. The hierarchical control structure consists of 3 levels; compensator, scheduling and planning layers. The compensator layer includes a set of state feedback compensators, feedforward compensators and state estimators. The scheduling and planning layers are incorporated with the approximate reasoning feature of the fuzzy model to form a fuzzy coordinator.