Power transformer core fault diagnosis using frequency response analysis

Power transformers are main devices in the performance of energy supply systems. Therefore, there is a great interest in its health state. Frequency response analysis (FRA) is nowadays an appreciated preventive technique used for transformer maintenance in order to detect winding displacements. But, in spite of the advantages of FRA, a systematic diagnosis procedure has not been still developed due to the physical meaning of the frequency response is not really obtained. Our research group has developed a three phase magnetic core model that provides the relations among the raw frequency response and the different parts inside the three phase transformer. Different effects of the magnetic core are recognized through different parameters of this model. A diagnosis procedure is available taking into account these parameters because the internal parts of the transformer are distinguished