Modeling and Simulation of Current Transformers with the EMTP/ATP program

This paper describe the modeling and simulation of current transformers (TC´s), used with protective relays, with data of tests of laboratory, of saturation and relation, determining its answer, regarding different conditions gives the electric system. The analysis of model it is based on the simulation of the TC´s, using the saturable transformer model from the ElectroMagnetic Transient Program (EMTP/ATP), and the comparison with oscillography records of the tests of saturation. For it conclude emphasizing the study of the TC´s as regards transitory phenomena in significant scenarios to establish the appropriate selection, assuring the reliability of the protective relays operation.