Investigation on the Factors Affecting Inrush Current of Transformers Based on Finite Element Modeling

A finite element model of a single phase transformer coupled with a voltage fed electric circuit is presented. The model can be used for various purposes. It is also capable to include the eddy-current effect in the core and/or in solid bars, if needed. A time-stepping finite element solution is used to study the influence of some major parameters on the inrush current level, including the primary winding distance from the core, the primary winding resistance, residual magnetic flux density in the core and its polarity. Simulation results showed a good agreement with corresponding test results