Synthesis of control systems for chemical plants

Synthesis of plant-wide control structures involves identifying control objectives that are consistent with the overall production goals and formulating control strategies in a multivariate environment. This is a complex task. A hierarchical framework is proposed in which the plant is vertically decomposed into a set of representations of different degrees of abstraction. Starting from the input-output level, we develop a control structure for the overall plant. Then, we move onto the next level where the model, the control objectives and the control strategies are being refined. This procedure is repeated until all levels of the plant have been analyzed. The hierarchy of control strategies can be integrated to form a multi-horizon control system. In this paper, the key conceptual steps of the methodology are being demonstrated.