MODELING OF IRON-LOSS COMPONENTS OF GRAIN-ORIENTED SILICON STEEL FOR ACCURATE CALCULATION OF CORE LOSSES OF POWER AND DISTRIBUTION TRANSFORMERS

Accurate estimation of iron-loss components of grain oriented silicon steel plays an important role in accurately predicting the core loss p erformance of power and distribution transformers. Existing practice a mong design engineers is to approximate the material iron loss perform ance by a simple curve-fit, like a polynomial. This paper presents the development of an improved analytical model which consists of terms t hat explicitly represent loss components contributing to the total iro n loss of the transformer core material. These are expressed in terms of the operating flux density, frequency, and lamination thickness. No t only is the developed model simple and practical, but it also provid es transformer design engineers with accurate understanding of the beh avior of each loss component. The results presented here demonstrate t he excellent accuracy resulted from using the model in calculating the transformer core loss performance at the design stage.