This paper dealt with simulation approach of the effect of type of material and cutting
method of three phases transformer core on magnetization curve as well as inrush current.
Different to the one of single phase transformer, flux density affected magnetization curve as well
inrush current are change every cycle of three phases sources even in a same point investigated.
In fact it is much more complex compared to a single phase transformer. Three kinds of material
and two cutting methods were investigated in order to understand how it affect the magnetization
curve as well as it inrush current. Investigation done is emphasized on simulation based on finite
element method. A simple mathematical approach is also done to obtain the peak value of inrush
current. The result showed that material and cutting method affect the magnetization curve and
inrush current significantly. The generated inrush current in different cutting method has the
difference about 6.8% while ST-37 material has the largest generated inrush current of about 9
times compared to ST-1008 and 4 times compared to ST-1010 material.