Modelagem matemática e simulação de transformadores de potência para ensaios de impulsos atmosféricos

Abstract

This study presents the transient response analysis of power transformers during high frequency lightning impulse applied directly or near of its terminals. In addition, a study of the internal distribution of overvoltages generated in the windings due to the transient is emphasized. Userfriendly visual software based on C++ resources was developed to compute elements that compose the electrical equivalent circuit of the transformer, as well as the circuit assembly, simulation parameters and SPICE netlist file. The netlist is employed to simulate the utilized model of the equipment representation during a voltage impulse. The equivalent circuit model is based on the construction characteristics of the power transformer. All program steps are generated automatically, the program user is only responsible for the data input related to the construction characteristics of the equipment, simulation parameters and interconnection of its terminals. The program is a powerful auxiliary tool in the generation of new transformer designs since it allows the internal verification of winding points that are not always available for measuring the voltage distribution during the lightning impulse transient