Analytical Prediction Model of Energy Losses in Soft Magnetic Materials Over Broadband Frequency Range

Accurately and efficiently estimating the energy losses in electrical steels over a large frequency bandwidth, particularly in the high-frequency regimes, is of great significance for the optimal design of magnetic components. However, the traditional loss models, e.g., Steinmetz equations, have intrinsic drawbacks of being empirical and thereby require large amount of measured data to identify models' coefficients. Base on the fact that the Statistical Theory of Losses (STL) provides a simple and general method for the interpretation and prediction of the energy losses in soft magnetic materials, and conventional applications of STL are limited to low-frequency range where the skin effect is negligible, a novel broadband analytical loss model is devised by introducing the fractional derivative concept into the simulation of classical eddy current loss in both low- and high-frequency domains, and proposing the energetic model to calculate the hysteresis loss component analytically under the framework of STL. Using such model, a few measured data are required, and the solving of the coupled nonlinear diffusion problem for high-frequency loss is thereby circumvented. The simulation and experimental results confirm the accuracy and efficiency of the proposed method.