Utilizando redes de petri coloridas hierárquicas no auxílio à recomposição de subestações.

Abstract

Substations connect all the power system, letting energy flow. They are composed by equipments that switch, change or regulate electrical voltage; work as a transfer and control stage in a power transmission system, directing and controlling electrical flow, changing voltage levels and also serving as a delivery stage to industrial customers. Substations must operate, without interruptions, in their nominal conditions, i.e., supplying all the loads they were projected to. However, substation blackouts, random events,although they are not wished,occurvery often. When substation blackouts occur, there are social and economic consequences. In this context, it is important the restoration of the substation services, in a safe and reliable way ,as soon as possible. In this work, a solution to restore a substation is proposed, using Hierarchical Coloured Petri Nets (HCPNs), in a safe, reliable, fast and efficient way. This solution avoids prohibited states, aiming to the safety. HCPNs guarantee correctness. This becomes this solution reliable. The presented dynamics in this solution makes it fast. This solution executes its task without time loss and in a correct way. This becomes this solution efficient. This solution has the advantages of not having difficulty of representing a knowledge base and/or projecting an efficient mechanism of inference to determine which actions have to be taken, from a large volume of knowledge based on rules; not having bad performance, working with multiple faults; not having dependency of operator knowledge. Moreover, this solution considers the detailed models of the substation equipments; has a dynamics which just allows updated information processing; is robust, i.e., if a problem to acquire some information or command some equipment occurs, alternative ways to accomplish substation restoration successfully are considered; is structured and systematized, causing an easy generalization and therefore facilitating a possible maintenance and/or ampliation of this system; proves, through formal methods, its correctness; is possible to integrate in a real case. As case study, a representative real substation is considered. Using formal methods, a formulation and solution to this problem through structured, scalable and compact mathematical representations are possible. Algorithms and proprieties of the used formalism let analysis formally. Generalization of the solution not only to several substations, but also to other plants, is also presented. A suggestion to integrate the proposed solution in real systems becomes this solution in a direct and practical application. This solution can be used by electrical companies what can represent relevant financial and operational gains.