Features of a hybrid expert system for security enhancement

Progress in combining analytical and rule-based programs for the purpose of power system security enhancement is reported. The emphasis is on the illustration of the details of the search process, the interaction between programs, and the role of heuristics. Security enhancement is an optimization problem. The concept for a hybrid expert system that performs a search through the space of the feasible operating states is developed. With the combination of a standard search algorithm with a production system a sophisticated search process is built up. This allows integrated analytical programs to provide the knowledge base with quantitative information about the network state and about the effects of control actions on the network state. An example is given of the application of the expert system. The results are presented, followed by a discussion of the effects of the variation of heuristic parameters on the search process