Study On Expert System Of Relay Protection Based On Analytic Hierarchy Process

The relay protection system is an important part of the power system, and produce significant influence for the safety and reliability of the power system’s operation and the normal working of relay protection’s important components. Some defects will appear when relay protection is working, which make the system ineffective or even affect the reliability of the power system. Eliminating these defects is an important part in the maintenance work of relay protection system.First of all, the composition of the relay protection system is introduced, and then this paper collects and arranges the typical defects of relay protection system, analyses the relations of their attributes:the defect’s name, appearance, reason and analysis, attention, processing step. According to this, data model has been built as the data source of expert system.The second, on the foundation of the traditional eliminating defects work, the analytic hierarchy process (AHP) has been introduced and a hierarchy optimization model was established. In view of the characteristics of eliminating defects, the model has been established by setting the optimization of eliminating defects as the goal, impacting factors as the criteria and fault location as the alternatives. The order of the fault position sorted by their final weights is the optimal result. This method turns traditional random order into the optimal order which considers the impacting factors, and efficiency of eliminating defects will be improved.In the end, an expert system of relay protection, which could made the operation of this method visual and calculation rapidly, has been developed according to the data model and the optimization model. It produces the final result of eliminating defects according to the data in the database, which gives the advantages of usage and promotion of this method.