Résumé : Petri nets (PN) provide powerful modeling and analytical framework for representing plants or systems, in general. On the other hand, there is a powerful mathematical theory on the supervisory control of discrete event system originally developed by Ramadge and Wonham. We combine these two paradigms in order to synthesize a combined plant+controller model. The significance of such a combined model are several folds: (1) The combined plant+controller model represents the controlled behavior of the system while the plant and the controller work together on a feedback loop basis. (2) It provides a single and a compact model for the functional and performance analysis of closed loop behavior of the plant and contoller , (3) The combined model lends itself more efficiently to the generation of an executable control code as it has all the inputs and outputs between the plant and the controller in one place.