An Improved Eddy Current Loss Model Over Broadband Frequency Range

Abstract

I IntroductionAccurate iron loss prediction is of great significance to the optimal design of electrical equipment[1]. At present, the application of silicon steel lamination in complex excitation greatly increases the difficulty of accurately predicting iron loss, especially eddy current loss. To solve the above problems, various eddy current loss prediction methods have been proposed[2]-[3], but these methods lack the physical background. A physical-based improved parametric magneto-dynamics (IPMD) model is proposed. For the sake of calculating the eddy current loss more accurately, the Tellinen (TLN) hysteresis model is used in the implementation of the IPMD model.II Improved Parametric Magneto-Dynamic ModelTo solve the problem of inaccurate calculation caused by nonuniform magnetic field distribution of silicon steel lamination at high frequency, the IPMD model based on one-dimensional Maxwell diffusion equation is proposed in this paper. In the IPMD model, the influence of hysteresis on magnetic field distribution is considered by coupling the TLN model, and the influence of skin effect at high frequency is considered by using the nonlinear segmentation method. The segmentation method divides the analysis area of silicon steel lamination into several slices and realizes the uniform expression of the magnetic field on a single slice. According to the characteristics of slow change of magnetic field of inner slice and fast change of magnetic field of outer slice, the thickness of outer slice is appropriately reduced and the thickness of inner slice is appropriately increased, as shown in Fig.1. By using the piecewise constant function to approximate the magnetic field distribution of silicon steel lamination, the eddy current loss can be accurately predicted by the IPMD model, as shown in Fig.2.III ConclusionThe IPMD model proposed in this paper can accurately predict the eddy current loss in a wide frequency range while considering the physical background, which has practical significance for the study of eddy current loss characteristics of soft magnetic materials.   An Improved Eddy Current Loss Model Over Broadband Frequency Range