DIAGNOSIS OF POWER TRANSFORMERS INSTALLED IN THE ABIDJAN SOUTH AREA IN COTE DIVOIRE USING DATABASES CONSISTING OF GAS ANALYSIS RESULTS DISSOLVED IN INSULATING OIL

The transformer is the most important piece of equipment in the electric power system used to transmit and distribute electricity. The oil/paper mixed insulation system is one of the essential parts due to the various defects that can be produced in this part. In general, the insulating oil contains about 70% of the information on the state of health of the power transformer. We received from the national electricity company the measurement data (Analysis of dissolved gases: AGD) made on transformers in the region of Abidjan Sud which we analyzed in order to detect defects. AGD is an effective technique for diagnosing and ensuring early detection of incipient faults in transformers and making decisions to reduce unplanned failures. The objectives of this research work were to give, from data analysis, the state of health of the transformers installed in the region of Abidjan Sud and to propose to the national electricity company as well as to the various Ivorian companies the most appropriate interpretation method for AGD. The interpretation methods used are: Doernenburg, Rogers, Duval, IEEE and IEC. The study on the different transformers made it possible to show that the IEC criterion had the best rate of correct analysis, while that of Doernenburg had the lowest rate. The state of health of the various processors was also highlighted.