Ghosh Mohendro Kumar, Gao Yanhui, Dozono Hiroshi, Muramatsu Kazuhiro, Guan Weimin, Yuan Jiaxin, Tian Cuihua, Chen Baichao
Department of Electrical and Electronic Engineering, Saga University, Saga 840-8502, Japan.
School of Electrical Engineering, Wuhan University, Wuhan 430072, PR China.
Heliyon. 2019 Aug 28;5(8):e02229. doi: 10.1016/j.heliyon.2019.e02229. eCollection 2019 Aug.
In the magnetic field analysis of magnetic devices using a ferrite core, such as a pulse transformer, the frequency-domain analysis is often carried out using the measured complex permeability under different frequency range. However, the nonlinear magnetic characteristics cannot be considered in the frequency-domain analysis because of the harmonics caused by it cannot be represented. The nonlinear magnetic characteristics can be considered in the time-domain analysis, but suitable constant conductivity and permittivity taking account of the microstructure of ferrite core, which can represent the measured complex permeability under different frequencies, needs to be investigated for the time-domain analysis. In this paper, the effective permeability of a toroidal ferrite core is tried to be demonstrated by using the linear ac steady state magnetic field analysis taking account eddy currents and displacement currents. It is shown that the measured permeability can be realized roughly by using the modified constant conductivity and permittivity. The nonlinear time-domain magnetic field analysis can be carried out using the modified constant conductivity and permittivity obtained from this paper.
在使用铁氧体磁芯的磁性器件（如脉冲变压器）的磁场分析中，频域分析通常是利用在不同频率范围内测量得到的复磁导率来进行的。然而，由于其产生的谐波无法被表示出来，频域分析中无法考虑非线性磁特性。非线性磁特性可以在时域分析中考虑，但对于时域分析而言，需要研究适合的、考虑铁氧体磁芯微观结构的恒定电导率和介电常数，其能够表示不同频率下测量得到的复磁导率。在本文中，尝试通过考虑涡流和位移电流的线性交流稳态磁场分析来证明环形铁氧体磁芯的有效磁导率。结果表明，使用修正后的恒定电导率和介电常数可以大致实现测量得到的磁导率。利用本文得到的修正后的恒定电导率和介电常数，可以进行非线性时域磁场分析。
