Guiding a power system restoration with an expert system

Minimizing the amount of time needed to restore a power system helps reduce the economic cost and the public´s resentment over the interruption of service. An expert system can help the operator achieve this goal by providing actualized restoration plans, dependable recommendations, and a clear picture of the situation. A hierarchical structure has been adopted for the prototype expert system described. This structure separates the selection of the next objective (strategic reasoning) from the development of a plan showing how this objective can be achieved (tactical reasoning). This separation enables the system to quickly adapt its recommendations when a problem arises during the restoration. Planning connection paths through substations of widely different configurations is greatly facilitated by the adoption of a hierarchical description of the topology of these substations. This knowledge representation scheme is the symbolic equivalent of the one-line diagrams used by the operators