基于介质损耗谱结构不敏感频率点的油纸绝缘受潮状态评估方法

doi:10.19595/j.cnki.1000-6753.tces.242093

Abstract
Figure/Table
References
Related Citation (15)

Download: PDF (5077 KB) HTML (1 KB)
Export: BibTeX | EndNote (RIS)

Abstract The moisture condition of oil-paper insulation significantly impacts the safe operation of oil-immersed electrical equipment. Accurately assessing the internal insulation moisture content is essential for ensuring the normal operation of such equipment. Dielectric response technology plays a critical role in the on-site, non-destructive evaluation of transformer insulation moisture conditions. However, existing evaluation models require input of typical parameter information representing insulation structures such as transformer oil and spacers, limiting the field application of this technology. This paper aims to explore a frequency-domain spectral feature independent of insulation structure differences and to develop a transformer moisture condition evaluation method that does not rely on insulation structure parameters.
Firstly, an experimental model simulating structures comprising insulating oil, spacers, and paperboard was used to measure the loss spectra of the overall oil-paper insulation structure and the oil-immersed insulating paper. Experimental results revealed that when structural parameter values deviate from actual values, the inversion results of the oil-impregnated insulation paper loss spectrum show significant deviations from the measured values. Loss spectra calculated using different X and Y values intersect at the same frequency point, while the moisture level only affects the position of this frequency point. This frequency point is defined in this paper as the “structure-insensitive characteristic frequency point”, denoted as the f₀ point, and its existence was validated for rationality. At the frequency point f₀, the voltages applied to each dielectric have the same phase angle, and the current in each dielectric has the same phase angle as its voltage. Under this specific condition, variations in X and Y only affect the magnitudes of voltage and current, without influencing the dielectric loss angle. Conversely, when the voltage frequency deviates from f₀, changes in the structural parameters X and Y alter the magnitudes and phases of voltage, and current in each part. Finally, based on a dielectric spectrum database of insulating paperboards constructed in the laboratory, this study compared the errors between the actual values and the overall oil-paper insulation loss spectra at the structure-insensitive characteristic frequency point for different moisture contents. The minimum error was used to determine the moisture content evaluation results. The evaluated moisture content of oil-paper insulation samples was very close to the actual measurements obtained through the Karl Fischer method. For equivalent main insulation models and actual oil-immersed electrical equipment, the evaluation results were reasonable and consistent with those of commercial equipment.
The experimental results lead to the following conclusions: (1) A frequency point f₀ exists in the loss spectrum of oil-paper insulation, satisfying the relationship tanδ_tot(f₀)=tanδ_paper(f₀)=tanδ_oil(f₀), independent of insulation structure parameters X and Y. This frequency point is defined as the “structure-insensitive characteristic frequency point”. Changes in moisture levels do not affect the existence of this point but only influence its specific value f₀. A moisture condition evaluation method based on the structure-insensitive characteristic frequency point f₀ was proposed. This method enables quantitative evaluation of the moisture content in oil-paper insulation without requiring insulation structure parameter information. Initial validation of this method’s effectiveness was demonstrated using a transformer main insulation equivalent physical model and oil-immersed electrical equipment.

Key words： Oil-paper insulation loss spectrum structure-insensitive frequency point moisture content

Received: 21 November 2024

PACS:

TM855

	Service

	E-mail this article
	Add to my bookshelf
	Add to citation manager
	E-mail Alert
	RSS
	Articles by authors
	Peng Yu
	Yang Lijun
	Li Jiajun
	Wang Jianyi
	Zhang Xiaoqin

Cite this article:

Peng Yu,Yang Lijun,Li Jiajun等. Evaluation Method of Oil-paper Insulation Damp State Based on the Structure-Insensitive Frequency Point of Loss Spectrum[J]. Transactions of China Electrotechnical Society, 2025, 40(23): 7737-7750.

URL:

https://dgjsxb.ces-transaction.com/EN/10.19595/j.cnki.1000-6753.tces.242093 OR https://dgjsxb.ces-transaction.com/EN/Y2025/V40/I23/7737

[1] 刘刚, 胡万君, 刘云鹏, 等. 降阶技术与监测点数据融合驱动的油浸式变压器绕组瞬态温升快速计算方法[J]. 电工技术学报, 2024, 39(19): 6162-6174.
Liu Gang, Hu Wanjun, Liu Yunpeng, et al.A fast calculation method for transient temperature rise of oil immersed transformer windings driven by fusion of order reduction technology and monitoring point data[J]. Transactions of China Electrotechnical Society, 2024, 39(19): 6162-6174.
[2] 江军, 张文乾, 李波, 等. 电力变压器油中溶解气体离群值识别和数据重构[J]. 电工技术学报, 2024, 39(17): 5521-5533.
Jiang Jun, Zhang Wenqian, Li Bo, et al.Outlier detection and data reconstruction of dissolved gas in oil for power transformers[J]. Transactions of China Electrotechnical Society, 2024, 39(17): 5521-5533.
[3] 邹阳, 林锦煌, 何津, 等. 基于频谱解构法的油纸绝缘扩展德拜模型参数辨识[J]. 电工技术学报, 2023, 38(3): 622-632.
Zou Yang, Lin Jinhuang, He Jin, et al.Parameter identification of oil paper insulation extended Debye model based on spectrum deconstruction method[J]. Transactions of China Electrotechnical Society, 2023, 38(3): 622-632.
[4] 吴明, 张大宁, 邵先军, 等. 基于微带环谐振器的油纸绝缘介电响应特性与受潮评估[J]. 电工技术学报, 2023, 38(3): 633-647.
Wu Ming, Zhang Daning, Shao Xianjun, et al.Dielectric response properties and moisture assess-ment of oil-paper insulation based on micro-strip ring resonator[J]. Transactions of China Electrotechnical Society, 2023, 38(3): 633-647.
[5] 杨定乾, 王进, 宋通, 等. 基于频域介电响应的油浸纸套管受潮缺陷诊断分析[J]. 高压电器, 2022, 58(6): 77-86.
Yang Dingqian, Wang Jin, Song Tong, et al.Diagnosis and analysis of moisture defect of oil-paper insulated bushing based on frequency domain dielectric response[J]. High Voltage Apparatus, 2022, 58(6): 77-86.
[6] 姚欢民, 穆海宝, 张大宁, 等. 时变温度下油纸绝缘频域介电谱曲线校正方法研究[J]. 电工技术学报, 2023, 38(1): 246-257.
Yao Huanmin, Mu Haibao, Zhang Daning, et al.Study on the frequency domain spectroscopy curves correction method of oil-paper insulation at time-varying temperature[J]. Transactions of China Electrotechnical Society, 2023, 38(1): 246-257.
[7] 夏源, 杨丽君, 吕晓露, 等. 基于介质响应电流频变特性的油纸绝缘受潮状态评估方法[J]. 电工技术学报, 2024, 39(11): 3444-3456.
Xia Yuan, Yang Lijun, Lü Xiaolu, et al.Evaluation method of oil-paper insulation damp state based on the frequency-dependent characteristics of dielectric response current[J]. Transactions of China Electro-technical Society, 2024, 39(11): 3444-3456.
[8] 张明泽, 刘骥, 齐朋帅, 等. 基于介电响应技术的变压器油纸绝缘含水率数值评估方法[J]. 电工技术学报, 2018, 33(18): 4397-4407.
Zhang Mingze, Liu Ji, Qi Pengshuai, et al.Numerical evaluation method for moisture content of transformer oil-paper insulation based on dielectric response technique[J]. Transactions of China Electrotechnical Society, 2018, 33(18): 4397-4407.
[9] Hu Yizhuo, Dong Ming, Song Bo, et al.Parameters extraction and mechanism analysis of the moisture in oil-paper based on the spectral decomposition of dielectric response[J]. IEEE Transactions on Dielec-trics and Electrical Insulation, 2022, 29(4): 1441-1449.
[10] Cui Yi, Ma Hui, Saha Tapan, et al.Understanding moisture dynamics and its effect on the dielectric response of transformer insulation[J]. IEEE Trans-actions on Power Delivery, 2015, 30(5): 2195-2204.
[11] 董明, 刘媛, 任明, 等. 油纸绝缘频域介电谱解释方法研究[J]. 中国电机工程学报, 2015, 35(4): 1002-1008.
Dong Ming, Liu Yuan, Ren Ming, et al.Explanation study of frequency-domain dielectric spectroscopy for oil-paper insulation system[J]. Proceedings of the CSEE, 2015, 35(4): 1002-1008.
[12] 张明泽, 孟繁昊, 刘骥, 等. 变压器油纸绝缘频域介电响应非线性特性研究[J]. 中国电机工程学报, 2023, 43(2): 831-843.
Zhang Mingze, Meng Fanhao, Liu Ji, et al.Research on nonlinear characteristics for frequency domain dielectric response of transformer oil-paper insulation[J]. Proceedings of the CSEE, 2023, 43(2): 831-843.
[13] 张大宁, 刘孝为, 詹江杨, 等. 变压器油纸绝缘频域介电谱的虚部分析[J]. 电工技术学报, 2019, 34(4): 847-854.
Zhang Daning, Liu Xiaowei, Zhan Jiangyang, et al.Analysis of imaginary part of frequency domain spectroscopy for oil-paper insulation transformer[J]. Transactions of China Electrotechnical Society, 2019, 34(4): 847-854.
[14] Shi Shilin, Hao Jian, Zeng Qian, et al.Moisture and aging degree evaluation method for oil-paper insulation based on HV-FDS characteristics analysis[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2024, 31(5): 2520-2530.
[15] 杜林, 冉鹂蔓, 蔚超, 等. 基于扩展德拜模型的油纸绝缘受潮频域特征量研究[J]. 电工技术学报, 2018, 33(13): 3051-3058.
Du Lin, Ran Liman, Wei Chao, et al.Study on frequency domain characteristics of moisture in oil-paper insulation based on extended Debye model[J]. Transactions of China Electrotechnical Society, 2018, 33(13): 3051-3058.
[16] 杨峰, 唐超, 周渠, 等. 基于等效电路的油纸绝缘系统受潮状态分析[J]. 电工技术学报, 2020, 35(21): 4586-4596.
Yang Feng, Tang Chao, Zhou Qu, et al.Analyzing the moisture state of oil-paper insulation system using an equivalent circuital model[J]. Transactions of China Electrotechnical Society, 2020, 35(21): 4586-4596.
[17] 黄猛, 李怡然, 吴延宇, 等. 计及界面电荷和极性效应的油纸复合绝缘非线性电路等效模型[J]. 电工技术学报, 2024, 39(11): 3422-3432.
Huang Meng, Li Yiran, Wu Yanyu, et al.Equivalent nonlinear circuit model with interface charge and polarity effect for oil-paper composite insulation[J]. Transactions of China Electrotechnical Society, 2024, 39(11): 3422-3432.
[18] Dong Ming, Ren Ming, Wen Fuxin, et al.Explanation and analysis of oil-paper insulation based on frequency-domain dielectric spectroscopy[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2015, 22(5): 2684-2693.
[19] 周利军, 李先浪, 王东阳, 等. 基于Havriliak-Negami介电弛豫模型的油纸绝缘状态评估[J]. 高电压技术, 2016, 42(1): 153-162.
Zhou Lijun, Li Xianlang, Wang Dongyang, et al.Status assessment of oil-paper insulation based on Havriliak Negami dielectric relaxation model[J]. High Voltage Engineering, 2016, 42(1): 153-162.
[20] Xu Qingchuan, Wang Shengkang, Lin Fuchang, et al.Moisture assessment of oil-immersed paper based on dynamic characteristics of frequency domain spectro-scopy[J]. IEEE Access, 2022, 10: 15183-15192.
[21] Tu Yalong, Wang Shengkang, Xu Qingchuan, et al.Study on XY model and its equivalent circuit of oil-paper insulation[J]. IEEJ Transactions on Electrical and Electronic Engineering, 2023, 18(4): 515-524.
[22] Fan Xianhao, Liu Jiefeng, Zhang Yiyi, et al.A modified XY model of transformer oil-paper insulation system including non-uniform aging and conductance effect[J]. IET Generation, Transmission & Distribu-tion, 2021, 15(13): 2008-2017.
[23] Blennow J, Ekanayake C, Walczak K, et al.Field experiences with measurements of dielectric response in frequency domain for power transformer diagnos-tics[J]. IEEE Transactions on Power Delivery, 2006, 21(2): 681-688.
[24] Gafvert U, Frimpong G, Fuhr J. Modeling of dielec-tric measurements on power transformers[C]//Proceedings of CIGRE, Paris, France, 1998: 15/103.
[25] Li Wei, Yang Lijun, Xia Yuan, et al.Assessment of the moisture content of oil-paper insulation based on the nonlinear coefficient of low-frequency-per-unit curve[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2022, 29(6): 2122-2130.
[26] 徐晴川, 王圣康, 林福昌, 等. 基于频谱二阶斜率方均根的变压器油浸绝缘纸频谱提取[J]. 电工技术学报, 2022, 37(19): 4989-5002.
Xu Qingchuan, Wang Shengkang, Lin Fuchang, et al.Frequency spectroscopy extraction of oil-immersed paper based on second-order gradient root mean square[J]. Transactions of China Electrotechnical Society, 2022, 37(19): 4989-5002.
[27] 邓映鑫, 杨丽君, 燕飞东, 等. 受潮油纸绝缘的非线性介电响应特性及H-W模型在时-频转换中的应用[J]. 电工技术学报, 2020, 35(21): 4609-4619.
Deng Yingxin, Yang Lijun, Yan Feidong, et al.Nonlinear dielectric response characteristics of damp oil-impregnated pressboard insulation and application of H-W model in time-frequency conversion[J]. Transactions of China Electrotechnical Society, 2020, 35(21): 4609-4619.
[28] 董明, 刘媛, 任明, 等. 油纸绝缘频域介电谱特征参数提取及绝缘状态相关性研究[J]. 中国电机工程学报, 2015, 35(23): 6246-6253.
Dong Ming, Liu Yuan, Ren Ming, et al.Study of characteristic parameter extraction and insulation condition correlation of frequency-domain dielectric spectroscopy for oil-paper insulation systems[J]. Proceedings of the CSEE, 2015, 35(23): 6246-6253.
[29] Xu Qingchuan, Wang Shengkang, Lin Fuchang, et al.Extracting frequency spectroscopy of oil-immersed paper based on havriliak-negami model without known insulation structure of transformer[J]. IEEE Transactions on Instrumentation Measurement, 2022, 71: 3181296.
[30] 杨丽君, 彭攀, 高竣, 等. 基于频域介电响应特征指纹的油纸绝缘受潮及老化状态区间识别[J]. 电工技术学报, 2018, 33(9): 2105-2114.
Yang Lijun, Peng Pan, Gao Jun, et al.The range recognition of moisture and aging status of oil-paper insulation based on frequency domain dielectric response characteristic fingerprint[J]. Transactions of China Electrotechnical Society, 2018, 33(9): 2105-2114.
[31] 范贤浩, 刘捷丰, 张镱议, 等. 融合频域介电谱及支持向量机的变压器油浸纸绝缘老化状态评估[J]. 电工技术学报, 2021, 36(10): 2161-2168.
Fan Xianhao, Liu Jiefeng, Zhang Yiyi, et al.Aging evaluation of transformer oil-immersed insulation combining frequency domain spectroscopy and support vector machine[J]. Transactions of China Electrotechnical Society, 2021, 36(10): 2161-2168.
[32] He Yuxin, Yang Lijun, Liu Xiong, et al.Moisture-diffusion behavior in oil-paper insulation based on terahertz time-frequency technology[J]. IEEE Trans-actions on Dielectrics and Electrical Insulation, 2024, 31(5): 2621-2631.