A Generalized Analytical Predictor for Process Control

The Generalized Analytical Predictor (GAP) controller proposed by Wong and Seborg is modified to include a generalized disturbance predictor. The resulting control structure (W-E GAP) is shown to contain the Wong and Seborg GAP (W-S GAP) as a special case. The disturbance predictor employed by the W-E GAP is formulated using the Internal Model Control (IMC) approach, and it dynamically predicts the effect of disturbances on the process output. IMC corresponds to the steady-state version of this disturbance predictor. Significant improvement in regulatory response is possible using the W-E GAP compared with IMC.