An expert system for protective relay setting of transmission systems

An expert system for setting protective relays in a high-voltage transmission system is proposed. Multilevel frames are used to represent relay specifications and system information. Setting rules are stored in the hierarchical rule base. The frame-based inference mechanism is adopted for an efficient integration of frame and rule. An easy system modification environment is achieved through predefined predicates and a frame editor. The use of the developed system expedites the relay setting process with increased accuracy and consistency regardless of the power system´s complexity.<>