Estudo das perdas em transformadores operando com carga não linear

Abstract

This work presents a study of the losses in the transformers in the presence of harmonics and an evaluation of the increase in the load with the increase of the distortion of the load current. Although the transformers are electrical devices with great efficiency, around 98%, the need to evaluate the behavior of the transformers is due to the increase of the nonlinear loads connected to the electric grid, which inject increasingly distorted load currents in the system, increasing loss of these devices. The large number of transformers in operation connected to non-linear loads generates a considerable waste of energy. The main losses in transformers are the iron losses and copper losses, also called core losses and winding losses. Using the PSIM software, the equivalent circuit model and the parameters of a distribution transformer, these losses are analyzed. The results show increased losses with increased distortion and frequency of voltage and current, as well as predict overload conditions for the simulated transformer model.