高频利兹线变压器漏感快速计算方法

doi:10.19595/j.cnki.1000-6753.tces.240527

Abstract
Figure/Table
References
Related Citation (15)

Download: PDF (10955 KB) HTML (1 KB)
Export: BibTeX | EndNote (RIS)

Abstract As an important parameter in power electronic converters, the leakage inductance of high-frequency transformers is of great significance in improving the operating mode and power transmission characteristics of isolated DC-DC converters. Compared with the solid round wire, the Litz wire can reduce eddy current losses in high-frequency magnetic components. However, the complicated structure of the Litz-wire windings poses a serious challenge to predicting leakage inductance in high-frequency transformers. On the one hand, it is difficult to precisely extract the magnetic field energy in various regions of the core window. On the other hand, it is hard to accurately characterize the multi-stranded and twisting structures of the Litz wires. Therefore, this paper presents a fast calculation method of leakage inductance in the high-frequency transformer with Litz-wire winding.
Firstly, a homogenized equivalent process for Litz wire is proposed to enhance the flexibility of modeling and the efficiency of computation. The magnetic field energy variation with frequency inside the Litz-wire conductors are analyzed. Then, the 2-D magnetic field energy inside the core window is extracted based on the method of images to eliminate the impact of the edge effect. The internal and external magnetic fields at different locations in the winding are accurately characterized by introducing the meshing into the method of images, and a coordinate transformation method is proposed to consider the twisting structure of the Litz wires. Finally, two high-frequency transformer prototypes with different structures are designed and fabricated. Compared with the measurement results and two existing methods, the accuracy and efficiency of the proposed approach are verified.
The following conclusions can be drawn. (1) A homogenized equivalent model of the Litz-wire twisting structure is developed by introducing the relative complex permeability, which simplifies the model building and reduces the computational cost. The variation of the magnetic field energy in the Litz wires with frequency is analyzed, and the magnetic field energy stored in the Litz wires gradually decreases with the frequency increase. (2) The meshing process is introduced into the method of images, and the coordinate transformation method is proposed to characterize the twisting structure of the Litz wire. It can counteract a part of the external magnetic field and reduce the magnetic field energy in the conductors. (3) Considering the twisting characteristics of the Litz wire and the high-frequency effect, a leakage inductance prediction model is developed based on the magnetic field energy variation with frequency. (4) The accuracy and efficiency of the proposed method are verified compared with the measurement and the current two analytical methods. The maximum error does not exceed 4% throughout the measurement frequency range, and the calculation time is about 20 seconds. Moreover, the proposed method can be effectively applied to fast iterative calculations in the optimal design of high-frequency transformers.

Key words： High-frequency transformer leakage inductance the method of images Litz-wire windings frequency-dependent characteristic

Received: 02 April 2024

PACS:

TM433

	Service

	E-mail this article
	Add to my bookshelf
	Add to citation manager
	E-mail Alert
	RSS
	Articles by authors
	Chen Tianyuan
	Zhao Zhigang
	Zheng Yuxuan
	Wang Kai

Cite this article:

Chen Tianyuan,Zhao Zhigang,Zheng Yuxuan等. Fast Calculation Method of Leakage Inductance in High-Frequency Transformer with Litz-Wire Winding[J]. Transactions of China Electrotechnical Society, 2025, 40(8): 2353-2364.

URL:

https://dgjsxb.ces-transaction.com/EN/10.19595/j.cnki.1000-6753.tces.240527 OR https://dgjsxb.ces-transaction.com/EN/Y2025/V40/I8/2353

[1] 陈润田, 李楚杉, 姚文熙, 等. 基于等效励磁电感的SiC串联器件型中压双有源桥变换器的软开关技术[J]. 电工技术学报, 2024, 39(12): 3732-3745.
Chen Runtian, Li Chushan, Yao Wenxi, et al.Soft-switching technique for medium voltage dual active bridge converter with series-connected SiC devices based on equivalent magnetizing inductance[J]. Transactions of China Electrotechnical Society, 2024, 39(12): 3732-3745.
[2] 胡钰杰, 李子欣, 罗龙, 等. 串联谐振间接矩阵型电力电子变压器高频电流特性分析及开关频率设计[J]. 电工技术学报, 2022, 37(6): 1442-1454.
Hu Yujie, Li Zixin, Luo Long, et al.Characteristic analysis of high-frequency-link current of series resonant indirect matrix type power electronics transformer and switching frequency design[J]. Transactions of China Electrotechnical Society, 2022, 37(6): 1442-1454.
[3] 蔡瑶, 卢志刚, 潘尧, 等. 计及多重差异的交直流混合多能微网多时间尺度优化调度[J]. 电工技术学报, 2024, 39(11): 3392-3410.
Cai Yao, Lu Zhigang, Pan Yao, et al.Multi-time-scale optimal scheduling of AC-DC hybrid multi-energy microgrid considering multiple differences[J]. Transactions of China Electrotechnical Society, 2024, 39(11): 3392-3410.
[4] 赵志刚, 白若南, 陈天缘, 等. 基于智能优化算法的高频变压器电磁结构优化设计[J]. 电工技术学报, 2024, 39(17): 5610-5625.
Zhao Zhigang, Bai Ruonan, Chen Tianyuan et al. Optimization design of electromagnetic structure of high frequency transformer based on intelligent optimization algorithm[J]. Transactions of China Electrotechnical Society, 2024, 39(17): 5610-5625.
[5] 汪涛, 骆仁松, 文继峰, 等. 基于辅助绕组的高频变压器绕组损耗测量方法[J]. 电工技术学报, 2022, 37(10): 2622-2630, 2655.
Wang Tao, Luo Rensong, Wen Jifeng, et al.A measurement method of winding loss for high-frequency transformer based on auxiliary winding[J]. Transactions of China Electrotechnical Society, 2022, 37(10): 2622-2630, 2655.
[6] Yin Hao, Lai Jidong, Ren Sheng, et al.An accurate calculation method of leakage inductance of high-frequency transformer with Litz wire winding considering irregular region[J]. IEEE Journal of Emerging and Selected Topics in Power Electronics, 2022, 10(6): 7441-7451.
[7] Dowell P L.Effects of eddy currents in transformer windings[J]. Proceedings of the Institution of Electrical Engineers, 1966, 113(8): 1387.
[8] 律方成, 郭云翔, 李鹏. 大功率中频变压器漏感计算及其校正方法[J]. 高电压技术, 2016, 42(6): 1702-1707.
Lü Fangcheng, Guo Yunxiang, Li Peng.Calculation and correction method for leakage inductance of high-power medium-frequency transformer[J]. High Voltage Engineering, 2016, 42(6): 1702-1707.
[9] 尹浩, 苏建徽, 赖纪东, 等. 中频圆导线变压器漏感的精确解析计算[J]. 电工技术学报, 2021, 36(15): 3211-3220.
Yin Hao, Su Jianhui, Lai Jidong, et al.Accurate analytical calculation of leakage inductance of round conductor transformer under the medium frequency[J]. Transactions of China Electrotechnical Society, 2021, 36(15): 3211-3220.
[10] Chen Bin.Analysis of effect of winding interleaving on leakage inductance and winding loss of high frequency transformers[J]. Journal of Electrical Engineering & Technology, 2019, 14(3): 1211-1221.
[11] Wu Y H, Shigematsu K, Omoto Y, et al.An investigation and proposal for accurate leakage inductance modeling based on dowell model[C]//2022 International Power Electronics Conference (IPEC-Himeji 2022-ECCE Asia), Himeji, Japan, 2022: 1964-1969.
[12] Ouyang Ziwei, Zhang Jun, Hurley W G.Calculation of leakage inductance for high-frequency trans-formers[J]. IEEE Transactions on Power Electronics, 2015, 30(10): 5769-5775.
[13] Bahmani M A, Thiringer T.Accurate evaluation of leakage inductance in high-frequency transformers using an improved frequency-dependent expression[J]. IEEE Transactions on Power Electronics, 2015, 30(10): 5738-5745.
[14] Mogorovic M, Dujic D.Medium frequency trans-former leakage inductance modeling and experimental verification[C]//2017 IEEE Energy Conversion Congress and Exposition (ECCE), Cincinnati, OH, USA, 2017: 419-424.
[15] Zhang Ke, Chen Wu, Cao Xiaopeng, et al.Accurate calculation and sensitivity analysis of leakage inductance of high-frequency transformer with Litz wire winding[J]. IEEE Transactions on Power Electronics, 2020, 35(4): 3951-3962.
[16] Tourkhani F, Viarouge P.Accurate analytical model of winding losses in round Litz wire windings[J]. IEEE Transactions on Magnetics, 2001, 37(1): 538-543.
[17] 刘星亮, 邱祁, 王若宇, 等. 基于有限元仿真的高频高压变压器分段绕组漏感设计方法[J]. 高电压技术, 2020, 46(2): 610-617.
Liu Xingliang, Qiu Qi, Wang Ruoyu, et al.Design method for leakage inductance of high-frequency high-voltage transformer with winding segmented based on finite element simulation[J]. High Voltage Engineering, 2020, 46(2): 610-617.
[18] Li Xinyang, Huang Weican, Cui Bin, et al.Inductance characteristics of the high-frequency transformer in dual active bridge converters[C]//2019 22nd Inter-national Conference on Electrical Machines and Systems (ICEMS), Harbin, China, 2019: 1-5.
[19] Shen Zhan, Wang Huai.Parasitics of orthocyclic windings in inductors and transformers[J]. IEEE Transactions on Power Electronics, 2021, 36(2): 1994-2008.
[20] Hoke A F, Sullivan C R.An improved two-dimensional numerical modeling method for E-core transformers[C]//Seventeenth Annual IEEE Applied Power Electronics Conference and Exposition, Dallas, TX, USA, 2002: 151-157.
[21] Igarashi H.Semi-analytical approach for finite-element analysis of multi-turn coil considering skin and proximity effects[J]. IEEE Transactions on Magnetics, 2017, 53(1): 7400107.
[22] Ollendorff F.Magnetostatik der massekerne[J]. Archiv Für Elektrotechnik, 1931, 25(6): 436-447.
[23] 张惠娟, 杨文荣, 李玲玲. 工程电磁场与电磁波基础[M]. 北京: 机械工程出版社, 2010.
[24] Eslamian M, Vahidi B.New methods for computation of the inductance matrix of transformer windings for very fast transients studies[J]. IEEE Transactions on Power Delivery, 2012, 27(4): 2326-2333.