Factors affecting localised flux and iron loss distribution in laminated cores

Abstract The paper reviews the increasing importance of iron losses in magnetic cores of transformers and rotating machines and shows how it can be better understood with an increased knowledge of flux distribution in the devices. The importance of an understanding of flux distribution in Epstein square testing is emphasized and some problems in Epstein measurement are discussed. The use of high permeability silicon-iron in transformer cores can cause a reduction of the building factor in some designs and it is shown how the flux distribution in such cores can be adversely affected and increase the building factor when high quality steel is used.