Electromagnetic Analysis Of Single-Phase Transformer Banks Under Sympathetic Inrush Phenomenon

Sympathetic inrush current phenomenon occurs when a transformer is switched on in a power network containing other transformers that are already energized. This interaction significantly changes duration and magnitude of transient magnetizing currents in the transformers involved and may lead to misoperation of these equipment. Therefore, in this paper it is presented the results of electromagnetic analysis due to sympathetic inrush and inrush current phenomenon among single-phase 50 MVA transformers in a power substation in the northern region of Brazil. For this purpose, the nine single-phase transformers installed at SE Guama forming three three-phase banks, were modeled in the ATP software to obtain the energization behavior. In this paper the electromagnetic analyzes are performed in steady state, so only the first peak is used. In this way, results of the electromagnetic behavior of transformers are presented and compared sympathetic inrush with inrush current.