2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/225810The place invariant method is well known as an elegant way to construct a Petri net controller. It is possible to use the constraint for preventing forbidden states. But in general case, the number forbidden states can be very large giving a great number of control places. In this paper is presented a systematic method to reduce the size and the number of constraints. This method is applicable for safe and conservative Petri nets giving a maximally permissive controller.Journée sur l'Instrumentation Industrielle J2I, ORAN : Algérie (2009)Information Theorytext