Analysis of Inductor Model Sufficiency in High-Frequency Power Electronics

This paper presents a comprehensive analysis and optimization framework for power inductor models used in power electronics applications. A methodology is proposed to identify inductor models with the minimum number of elements sufficient to accurately reproduce current waveforms and power losses, for various core and winding configurations, based on current-waveform and power-loss fitting errors, explicitly highlighting the performance benefits of the selected models. The analysis focuses on inductor models, omitting the parasitic capacitance and the effect of core saturation. The evaluated inductor models are systematically classified and characterized using a rigorous analytical approach, which is illustrated through circuit simulations. To illustrate the practical feasibility of the proposed approach, experimental tests were carried out across widely used power electronics inductors. The models were identified and evaluated on the same measured waveforms; the reported errors are therefore fitting errors evaluated on the identification data. The results show that the selected models reproduce the measured current waveforms and power losses with low fitting errors and reproduce the measured division of losses between the core and the winding.