Modelling dynamic hysteresis loops and iron losses by the use of equivalent circuits

摘要

Purpose - The aim of the paper is the formulation of a simple hysteresis model entirely based on generally accepted concepts. Design/methodological/approach - According to this, the modelling of loops has been achieved by the application of the Langevin-Weiss law of magnetization to transformer equivalent circuits. The loops are generated by the change of the phase of current, introduced by the resistance modelling iron loss. Differential circuit equations have been solved with the help of standard Mathcad procedures. Findings - In spite of the simplicity of such approach, the accuracy of hysteresis loops and iron loss approximations is better than in PSpice simulations and the model can be easily extended to dynamic loops. Research limitations/implications - The application of the model is limited to lower frequencies, where the rise of frequency leads to the widening of the loops without the radical change of their shapes. Practical implications - Presented approach may be useful in simplified analysis of low frequency transformer circuits and in the primary explanation of hysteresis phenomena for teaching purposes. What is original/value of paper - Contrary to other models based on saturation curves, the dynamic hysteresis loops presented in this paper are obtained with the use of basic laws and concepts, without the introduction of any additional assumptions and the separate treatment of the lower and upper branches of the loops.