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.

Iron Loss Calculation Methods for Numerical Analysis of 3D-Printed Rotating Machines: A Review

“…The coefficients can be obtained from a function fitting to the experimental data on different frequencies. This is the Bertotti model, which is widely used in the industry [116,119,[125][126][127][128]. This and the modified Bertotti model, where the sum of the hysteresis losses at different frequencies is used to model the hysteresis loss of the material [129], is implemented in many commercial FEM tools (Flux [30,130,131]) [92,130,132,133].…”

“…Some recent studies have shown that more-accurate results can be achieved if the third anomalous loss coefficient is omitted, in the case of non-oriented steels [117,125,134,135]. These formulas can be written in the following form:…”