Determine the Short Circuit cutting Time of Fuse Cut Out for Energy saving Amorphous Core Transformers

In this article, we use the finite element method (FEM) with Ansys Electromagnetics to imilate two Amorphous core transformers (ACTs) with a capacity of 400kVA and 1600kVA; working in rated modes and three phase short circuit (SC) on the low voltage winding (LVW). From there, the largest SC current can be determined; and the largest SC electromagnetic force (EMF) have an effect on the LVW and high voltage winding (HVW) of ACTs. At the same time, research and build and coordinate between the Ampere-second characteristics of the ACTs and the characteristics of the fuse cut out (FCO), thereby determining the correct SC cutting time of the ACTs. We determine the correct SC cut-off time to support the correct FCO selection, from which the ACTs will avoid the harmful effects of EMF that cause the winding ACTs to break. The results of this study help us determine the correct time to cut off the SC of the FCO to disconnect the ACTs from the high voltage grid. From there, protect against SC breakage and displacement of the ACTs’s winding caused by SC EMF.