Modelos para surtos para transformadores de média tensão

Abstract

Nowadays, in power systems, the concept of reliability is getting more and more importance. Therefore, it is a tough task to take any equipment out of operation to carry out some tests in order to know its behavior under some phenomena that can occur in the power system (short-circuit, energization, transferred surges, etc.). The improvement of the computer systems allowed that even the most complex calculations could be ready quickly. Thus, the evaluation of the behavior of the power system equipments can be done almost in a real-time way. The development of models of these equipments that presents a good attachment with their actual behavior avoids them to be taken out of operation and then, the power system reliability is maintained. This work aims at getting a model to carry out high frequency studies (Transformer Transfer Function and Transferred Voltage). This work also aims getting at a transformer winding model in order to make it easier the evaluation of some signals that appear in the current wave shape obtained during the lightning impulse tests. Simulations are carried out and comparisons between their results and testing one are presented.