Transformer Status Indicator (TSI) as a new expert system for integrating the diagnostic results of power transformers

The power transformers are the most important and expensive equipments in the electrical transmission systems. The transformers average age in the power system in Hungary is approximately 25-30 years. It is not economical to change these equipments only because of their age. The Operators have to know and manage more information about the insulation, because the status of the insulation is determine the expectation time. A transformer only can be operated efficiently, reliably and economically, if we know its actual state expanding on all essential information. The operational reliability is influenced the most by the quality of the insulation but even other state markers/features play an important role. There are a lot of things what effect the status of the insulation. This paper introduces the advantages of Transformer Status Indicator (TSI). The TSI is an expert system, what is considering the essential parameters of the insulation. The TSI factor contains the environmental influences, operating values and diagnostic results, too.