Implementação de um relé virtual de proteção diferencial de transformadores: Avaliação de cenários de curtos-circuitos, inrush e saturação de TCs

Abstract

The transformer is one of the main pieces of equipment in the electrical system, being of vital importance for the delivery of electrical energy to consumer centers. Therefore, care must be taken, and these equipment’s must be carefully protected. One way to protect it against internal faults is to apply the differential protection function. The response of this function must be carefully analyzed for internal short circuit conditions, for which it is designed, and for conditions that can cause it to act improperly, such as external short circuits, current transformer saturation and transformer energization. Thus, in this work the implementation of a virtual transformer differential protection relay to evaluate such conditions is presented. For this, Matlab software is used to elaborate all the processing steps that make up a numerical relay. The main results are presented and confronted with the state of the art related to the theme.