Hybrid Modeling and Optimal Control of an Asphalt Base Process

This paper addresses the issue of an optimal selection of the production and delivery plan for an asphalt base process. The process is modeled as a DHA (Discrete Hybrid Automaton) using the high level modeling language HYSDEL (HYbrid System DEscription Language) that allows converting the DHA model into an MLD (Mixed Logical Dynamical) model. The proposed solution applies to a class of optimal control problems where the goal is to minimize the total completion time. The solution algorithm, which takes into account a model of a hybrid system described as an MLD system, is based on the reachability analysis. The algorithm abstracts the behavior of the hybrid system into a “tree of evolution”, where nodes of the tree represent reachable states of the system and branches connect two nodes if a transition exists between the corresponding states. To each node the cost function value is associated and, based on this value, the tree exploration is driven, searching for the optimal control profile.