Analysis and Calculation of High-frequency Loss of Incompletely-twisted Litz Wire

被引：0
|
作者：
Chen B. [1 ,2 ]
Tao X. [1 ,2 ]
Wan N. [3 ]
Fang C. [1 ,2 ]
Tang B. [1 ,2 ]
机构：
[1] Hubei Provincial Engineering Technology Research Center for Power Transmission Line, Yichang
[2] College of Electrical Engineering & New Energy, China Three Gorges University, Yichang
[3] Yichang Electric Company, State Grid Hubei Electric Power Company, Yichang
来源：
Gaodianya Jishu/High Voltage Engineering | 2023年 / 49卷 / 05期
基金：
中国国家自然科学基金;
关键词：
finite element method; high-frequency loss; incompletely-twisted structure; Litz wire; segmented equivalent circuit method;
D O I：
10.13336/j.1003-6520.hve.20211960
中图分类号：
学科分类号：
摘要：
The existing loss calculation model of Litz wire is generally based on the assumption that each insulated conductor flows through the same current. The model is derived from the one-dimensional and two-dimensional current density and eddy current field function of copper foil and round solid conductor, in which the influence of incompletely twisted structure on the current distribution between strands is ignored, thus it has a low calculation accuracy. In order to solve the accurate mathematical representation of the high-frequency losses of the Litz wire, we first systematically analyzed the magnetic field distribution, current density distribution, and the characteristics of the twisted structure of the Litz wire under the high-frequency condition. Then, based on the structure of the Litz wire strands, the accurate loss calculation method of Litz wire was established through the segmented equivalent circuit method and the finite element method (FEM). The Litz wire in the complete twisting pitch was segmented and equivalent to the inductance cell of the linear structure. The impedance matrix between the strands was calculated by the 2D FEM, and then the strand current vector was solved according to the system equation. Finally, the new method, the traditional analytical method, and the three-dimensional finite element method were compared and analyzed from the point of view of calculation accuracy and calculation amount for three typical Litz wire twisted structures. The results show that the new method can be adoped to quickly and accurately calculate the high-frequency loss resistance of different twisted Litz wires, and the maximum relative deviation is less than 2.34%. With the help of the new method, the influence of the twisted structure and frequency on the high frequency loss resistance and current flow mode of Litz wire is clarified. © 2023 Science Press. All rights reserved.
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页码：2180 / 2193
页数：13
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