Calculation Model and Conductivity Calculation Method for Iron Core Loss of Ferromagnetic Materials for Ultra-Low Temperature Working Conditions
Yang Zhifei1, Ge Baojun1, Dong Chuanyou1, Wang Likun1, Li Guanglin2
1. National and Local Joint Engineering Research Center of Large Electric Machines and Heat Transfer Technology Harbin University of Science and Technology Harbin 150080 China; 2. Shougang Zhixin Electromagnetic Materials Research and Development (Beijing) Co. Ltd Qian’an 064404 China;
Abstract：The High-speed permanent magnet motors used for transporting liquefied natural gas (LNG) operate in ultra-low temperature environments below -161℃. If the temperature rise of the motor is too high, it can easily cause LNG to vaporize, and the iron loss of the motor is the main factor affecting its temperature rise. Accurately calculating the loss characteristics of iron core materials in ultra-low temperature environments can help analyze the iron loss of the motor. Electric motors usually use silicon steel sheets as the iron core material. Their iron core losses will inevitably differ between ultra-low and normal temperatures, and their conductivity is challenging to measure in ultra-low temperatures. This paper studies the influence of ultra-low temperatures on the loss characteristics of silicon steel sheets, establishes a calculation model for iron core loss of ferromagnetic materials, and proposes a calculation method for the equivalent conductivity of ferromagnetic materials. Firstly, the SY-8258 magnetic property measurement system is used to measure the losses of silicon steel sheets at room and ultra-low temperatures. Then, a calculation model for iron core loss of ferromagnetic materials is established, and the shortcomings of the traditional model are explained. Furthermore, an improvement is made by introducing the relative loss coefficient and temperature coefficient correction factors. The loss values calculated by this model are compared with the measured values. Secondly, a method for calculating the equivalent conductivity of silicon steel sheets is proposed, and its effectiveness is verified by comparing the calculated and actual conductivity values of silicon steel sheets. This method is applicable to ultra-low temperature conditions and can also calculate the equivalent conductivity of silicon steel sheets at any ambient temperature. It should be noted that the following conditions are to be met: (1) the temperature inside and outside the silicon steel sheet has been kept constant; (2) obtain accurate iron consumption measurement results of silicon steel sheets at the ambient temperature. The following conclusions are drawn from the results. (1) Under ultra-low temperature conditions, the loss value of silicon steel sheets increases compared to room temperature. (2) The proposed loss calculation model has higher accuracy than traditional loss calculation models, which can calculate the loss of ferromagnetic materials in ultra-low temperature environments. (3) The proposed equivalent conductivity method calculates the equivalent conductivity of silicon steel sheets at room temperature. The results show that the percentage errors between the calculated and actual values are 4.4% and 6.6%, respectively.
杨志飞, 戈宝军, 董传友, 王立坤, 李广林. 面向超低温工况需求的铁磁材料铁心损耗计算模型与电导率计算方法[J]. 电工技术学报, 2025, 40(18): 5776-5785.
Yang Zhifei, Ge Baojun, Dong Chuanyou, Wang Likun, Li Guanglin. Calculation Model and Conductivity Calculation Method for Iron Core Loss of Ferromagnetic Materials for Ultra-Low Temperature Working Conditions. Transactions of China Electrotechnical Society, 2025, 40(18): 5776-5785.
[1] 戈宝军, 温亚垒, 王立坤, 等. LNG泵用低温高速永磁电机转子摩擦损耗研究[J]. 电机与控制学报, 2021, 25(10): 31-38. Ge Baojun, Wen Yalei, Wang Likun, et al.Research on rotor friction loss of cryogenic high-speed permanent magnet motor for LNG pump[J]. Electric Machines and Control, 2021, 25(10): 31-38. [2] 艾程柳, 黄元峰, 王海峰, 等. 潜液式LNG泵低温电机及其关键技术发展综述[J]. 中国电机工程学报, 2014, 34(15): 2396-2405. Ai Chengliu, Huang Yuanfeng, Wang Haifeng, et al.Development of the cryogenic electrical motor for the submerged liquid natural gas pump and its key technologies[J]. Proceedings of the CSEE, 2014, 34(15): 2396-2405. [3] 李佳欣, 鲍晓华, 狄冲, 等. 充水式潜水电机温度场仿真分析[J]. 电气工程学报, 2024, 19(1): 141-149. Li Jiaxin, Bao Xiaohua, Di Chong, et al.Simulation analysis of temperature field of the water-filled submersible motor[J]. Journal of Electrical Engin-eering, 2024, 19(1): 141-149. [4] 马伟明. 关于电工学科前沿技术发展的若干思考[J]. 电工技术学报, 2021, 36(22): 4627-4636. Ma Weiming.Thoughts on the development of frontier technology in electrical engineering[J]. Transactions of China Electrotechnical Society, 2021, 36(22): 4627-4636. [5] 马伟明, 王东, 程思为, 等. 高性能电机系统的共性基础科学问题与技术发展前沿[J]. 中国电机工程学报, 2016, 36(8): 2025-2035. Ma Weiming, Wang Dong, Cheng Siwei, et al.Common basic scientific problems and development of leading-edge technology of high performance motor system[J]. Proceedings of the CSEE, 2016, 36(8): 2025-2035. [6] Steinmetz C P.On the law of hysteresis[J]. Transactions of the American Institute of Electrical Engineers, 1892(9): 3-64. [7] Bertotti G.Physical interpretation of eddy current losses in ferromagnetic materials. I. theoretical considerations[J]. Journal of Applied Physics, 1985, 57(6): 2110-2117. [8] Bertotti G.Physical interpretation of eddy current losses in ferromagnetic materials. II. analysis of experimental results[J]. Journal of Applied Physics, 1985, 57(6): 2118-2126. [9] Bertotti G.General properties of power losses in soft ferromagnetic materials[J]. IEEE Transactions on Magnetics, 1988, 24(1): 621-630. [10] Kowal D, Sergeant P, Dupré L, et al.Comparison of iron loss models for electrical machines with different frequency domain and time domain methods for excess loss prediction[J]. IEEE Transactions on Magnetics, 2015, 51(1): 6300110. [11] 郭柏龄, 迟青光, 陈吉超. 实际工况下机车牵引变压器铁心损耗模型建立与验证[J]. 电工电能新技术, 2024, 43(2): 39-46. Guo Bailing, Chi Qingguang, Chen Jichao.Esta-blishment and verification of core loss model of locomotive traction transformer under actual working conditions[J]. Advanced Technology of Electrical Engineering and Energy, 2024, 43(2): 39-46. [12] 马阳阳, 李永建, 孙鹤, 等. 基于深度置信网络算法的面向铁磁材料旋转磁滞损耗的矢量磁滞模型[J]. 电工技术学报, 2023, 38(15): 4063-4075. Ma Yangyang, Li Yongjian, Sun He, et al.Vector hysteresis model for rotational hysteresis loss of ferromagnetic materials based on deep belief network algorithm[J]. Transactions of China Electrotechnical Society, 2023, 38(15): 4063-4075. [13] 赵志刚, 贾慧杰, 刘朝阳, 等. 考虑PWM波形特征的纳米晶磁心损耗模型的研究及验证[J]. 电工技术学报, 2024, 39(6): 1602-1612. Zhao Zhigang, Jia Huijie, Liu Zhaoyang, et al.Research and verification of nanocrystalline core loss model considering PWM waveform characteristics[J]. Transactions of China Electrotechnical Society, 2024, 39(6): 1602-1612. [14] 代岭均, 邹亮, 郭凯航, 等. 纳米晶合金晶粒尺寸与体积分数对高频磁损耗特性影响分析[J]. 电工技术学报, 2023, 38(18): 4853-4863. Dai Lingjun, Zou Liang, Guo Kaihang, et al.Analysis of grain size and volume fraction of nanocrystalline alloy on high frequency magnetic loss characteri-stics[J]. Transactions of China Electrotechnical Society, 2023, 38(18): 4853-4863. [15] Zhang Yu, Pillay P, Ibrahim M, et al.Magnetic characteristics and core losses in machine laminations: high-frequency loss prediction from low-frequency measurements[J]. IEEE Transactions on Industry Applications, 2012, 48(2): 623-629. [16] 赵志刚, 赵安琪, 王丽美, 等. 计及饱和磁化的铁磁材料EEL损耗模型研究[J]. 电工电能新技术, 2023, 42(12): 1-9. Zhao Zhigang, Zhao Anqi, Wang Limei, et al.Study on EEL loss model of ferromagnetic materials including saturation magnetization[J]. Advanced Technology of Electrical Engineering and Energy, 2023, 42(12): 1-9. [17] 林希, 张浩民, 刘振祥. 基于收缩因子改进PSO算法的J-A磁滞模型参数辨识[J]. 电气工程学报, 2024, 19(1): 187-195. Lin Xi, Zhang Haomin, Liu Zhenxiang.Parameter identification of J-A dynamic hysteresis model based on an improved constriction factor PSO algorithm[J]. Journal of Electrical Engineering, 2024, 19(1): 187-195. [18] 陈彬, 王川源, 刘洋, 等. 基于磁导-电容类比法和解析Preisach模型的铁心动态磁滞建模方法[J]. 电工技术学报, 2024, 39(18): 5576-5587. Chen Bin, Wang Chuanyuan, Liu Yang, et al.Dynamic hysteresis modeling method for iron core based on permeance-capacitance analogy and analytic preisach model[J]. Transactions of China Electro-technical Society, 2024, 39(18): 5576-5587. [19] 陈昊, 李琳, 刘洋. 基于Energetic模型的机械应力作用下电工钢片磁滞特性模拟[J]. 电工技术学报, 2023, 38(12): 3101-3111. Chen Hao, Li Lin, Liu Yang.Simulation of magnetic hysteresis characteristics of electrical steel sheet under mechanical stress based on Energetic model[J]. Transactions of China Electrotechnical Society, 2023, 38(12): 3101-3111. [20] 王书恒, 赵世伟, 景弋洋, 等. 高速永磁电机铁耗精确计算两项式模型[J]. 微电机, 2024, 57(5): 1-6, 22. Wang Shuheng, Zhao Shiwei, Jing Yiyang, et al.A two-term model for accurate calculation on iron losses of high-speed permanent magnet motors[J]. Micromotors, 2024, 57(5): 1-6, 22.
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