Evaluation of Power Transformer Differential Protection Using the ATP Software

This paper aims to present a methodology for performance evaluation of power transformers differential protection using the software ATP. In order to do so, the MODELS language is used to model a numerical relay that implements phase, negative sequence and restricted earth fault differential protective functions. The performance evaluation of the power transformer protection was done using a power system model whose parameters were obtained from real data. The results reveal the performance of the implemented protective functions facing to a wide variety of operating situations to which they may be subjected to. Accordingly, one can point out advantages of this kind of modeling, which leads to the appropriate choice and better understanding of power transformers differential protection settings.