Modeling of core loss for non-oriented electrical steel

Abstract

Purpose The purpose of this paper is to present the application of the loss approximation method for non-oriented electrical steel developed by the authors. A new model of a toroidal sample with dimensions ensuring high uniformity of the field was presented. Design/methodology/approach A critical analysis of the methods used was carried out. Based on these considerations, the authors proposed their own loss approximation method, which allows obtaining high accuracy in a wide range of induction and frequency. The proposed method is based on the assumption that for a certain frequency range losses can be describe by two terms formula. For a fixed value of the peak flux density Bm, the graph of specific loss divided by the frequency should have the form of a straight line. Then, the obtained coefficients for different Bm are the basis for approximation with the power function. Findings The comparison of measurement and approximation results shows that the method allows to obtain very good accuracy in a wide range of induction and frequency. Research limitations/implications More detailed studies on the impact of cutting on a larger number of samples with different geometrical dimensions are needed. Practical implications Application of the new method provides a better approximation of the curve of the loss and thus a more accurate calculation of the core loss in the electrical machines. Originality/value The paper presents the application of the loss approximation method for non-oriented electrical steel developed by the authors. A new model of a toroidal sample with dimensions ensuring high uniformity of the field was presented. It is shown that the approximation introduced allows for high accuracy in a wide range of frequency and magnetic flux density.