电热协同老化应力下环氧树脂复合材料沿面闪络特性与数值模拟

doi:10.19595/j.cnki.1000-6753.tces.240904

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Abstract Dry-type transformer is to high voltage level, high power density direction, long-term operation in the electro-thermal cooperative multi-stress complex working conditions such as epoxy resin casting insulation is more likely to induce along the surface flashover failure. In order to study the characteristics of epoxy resin along the surface flashover under the stress of electro-thermal cooperative aging, this paper builds a platform for flashover along the surface under AC stress, and it is found that when the aging temperature is 160℃, the flashover field strength of the epoxy resin specimen aged for 80 days is 2.11 kV/mm, which is a decrease of 25.7%. The steepest decrease in the field strength along the surface is found from 0 to 40 days, which is related to the rapid increase in the surface roughness of the specimen from 0 to 40 days.
A plasma model of epoxy resin flashover along the surface is established by combining the continuity equation of charged particles, the average electron energy equation and the interfacial reaction characterization equation, and the dynamic simulation of flashover along the surface at the working frequency is realized. According to the results of the aging experiment, a random function is introduced to change the surface roughness of the medium, and the dielectric constant after aging is combined to simulate the accurate electro-thermal aging behavior of the epoxy resin, and the temporal and spatial evolution laws of the tangential electric field strength, electron density and surface charge density of the epoxy resin in the process of flashover before and after aging are obtained. The simulation results show that the electron density and surface charge density increase during the flashover development of the aging epoxy resin, and the electric field strength at the head of the flow injection reaches 1.183 kV/mm at 12 ns, an increase of nearly 10.87%. With the aging specimen due to the roughness and dielectric constant increase, its surface charge density will occur surge phenomenon, compared with the aging specimen before the increase of 57.66%, so that the electron density quickly reached the threshold value of the electron collapse to flow injection, resulting in the development of the flashover becomes faster.
The mechanism of combined electro-thermal aging on the surface charge of epoxy resin specimens is explained by the trap effect, and the reason for the decrease in the flash field strength of the specimens is clarified. For the specimen aged for 80 days, the deep trap density and energy level increase to 2.56×10¹⁶ eV^-1·m^-3 and 1.06 eV, respectively, resulting in an increase in the probability of charge entry trapping, which leads to a large amount of surface charge accumulation, and the electric field distortion becomes more serious, thus decreasing the flash-coincidence field strength along the surface. The above findings provide theoretical and methodological basis for the fault operation and maintenance and life prediction of dry-type transformers.

Key words： Epoxy resin electrothermal joint aging flashover along the surface plasma surface traps

Received: 28 May 2024

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TM855

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	Li Sigeng
	Li Qingmin
	Wang Wei
	Jin Hu
	Li Ruihai

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Li Sigeng,Li Qingmin,Wang Wei等. Characterization and Numerical Simulation of Epoxy Resin Composites Flashed along the Surface under Electro-Thermal Co-Aging Stresses[J]. Transactions of China Electrotechnical Society, 2025, 40(13): 4045-4057.

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https://dgjsxb.ces-transaction.com/EN/10.19595/j.cnki.1000-6753.tces.240904 OR https://dgjsxb.ces-transaction.com/EN/Y2025/V40/I13/4045

[1] 李庆民, 刘伟杰, 韩帅, 等. 环氧树脂绝缘高频电热联合老化中局部放电特性分析[J]. 高电压技术, 2015, 41(2): 389-395.
Li Qingmin, Liu Weijie, Han Shuai, et al.Analysis on partial discharge characteristics of epoxy resin insulation during high-frequency electrical-thermal aging[J]. High Voltage Engineering, 2015, 41(2): 389-395.
[2] 谢珂, 卢森微, 邵春, 等. 等离子体梯度氟化提升非均匀电场下环氧树脂沿面闪络性能的研究[J]. 绝缘材料, 2023, 56(10): 75-83.
Xie Ke, Lu Senwei, Shao Chun, et al.Study on surface flashover performance of epoxy resin improved by plasma gradient fluorination under non-uniform electric fields[J]. Insulating Materials, 2023, 56(10): 75-83.
[3] 李泳霖, 黄世龙, 刘云鹏, 等. 考虑湿度气压影响的瓷绝缘子沿面类辉光放电仿真及其紫外光谱特性分析[J]. 电工技术学报, 2023, 38(7): 1956-1969.
Li Yonglin, Huang Shilong, Liu Yunpeng, et al.Simulation and ultraviolet spectral characteristics of glow-like discharge along the surface of porcelain insulators considering the influences of the humidity and atmospheric pressure[J]. Transactions of China Electrotechnical Society, 2023, 38(7): 1956-1969.
[4] 解曾祺, 韩耀萱, 李志辉, 等. 高导热氮化铝/环氧树脂复合材料的高频沿面放电特性[J]. 中国电机工程学报, 2024, 44(13): 5374-5386.
Xie Zengqi, Han Yaoxuan, Li Zhihui, et al.High frequency surface discharge characteristics of aluminum nitride/epoxy resin composites with high thermal conductivity[J]. Proceedings of the CSEE, 2024, 44(13): 5374-5386.
[5] 段玉兵, 韩明明, 王兆琛, 等. 不同热老化温度下高压电缆绝缘特性及失效机理[J]. 电工技术学报, 2024, 39(1): 45-54.
Duan Yubing, Han Mingming, Wang Zhaochen, et al.Insulation characteristics and failure mechanism of high-voltage cables under different thermal aging temperatures[J]. Transactions of China Electro-technical Society, 2024, 39(1): 45-54.
[6] 徐洋, 刘卫东, 高文胜. GIS绝缘子内部缝隙的局部放电特性和机理研究[J]. 高压电器, 2020, 56(7): 116-122.
Xu Yang, Liu Weidong, Gao Wensheng.Research on the characteristics and mechanism of partial discharge of internal crevice in GIS insulator[J]. High Voltage Apparatus, 2020, 56(7): 116-122.
[7] 常亚楠, 李庆民, 王健, 等. 交流GIS提上式微粒陷阱优化设计方法[J]. 高压电器, 2023, 59(3): 14-21.
Chang Yanan, Li Qingmin, Wang Jian, et al.Optimal design method of lifting particle trap in AC GIS[J]. High Voltage Apparatus, 2023, 59(3): 14-21.
[8] Bordeori M M, Gupta N.Electrochemical changes in epoxy resin due to thermal aging and their effect on electrical tree growth[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2022, 29(5): 1940-1947.
[9] Li Guochang, Hu Kai, Sun Weixin, et al.The influence of thermal aging on the surface trap characteristics and surface flashover of epoxy resin[J]. Journal of Solid State Science and Technology, 2023, 12(10): 103017.
[10] 黄炎光, 易鹭. 热老化对干式变压器环氧树脂介电性能的影响[J]. 绝缘材料, 2016, 49(9): 53-56, 60.
Huang Yanguang, Yi Lu.Effect of thermal ageing on dielectric property of epoxy resin for dry-type transformer[J]. Insulating Materials, 2016, 49(9): 53-56, 60.
[11] Bian Bo, Xia Guowei, Li Jingwei, et al.Thermal-aging characteristics of epoxy/glass fiber composite materials fordry-typeair-core reactors[J]. Polymer Composites, 2021, 42(8): 3773-3785.
[12] 梁英, 靳哲, 张君成. 硅橡胶在不同电晕老化阶段下的表面电荷对沿面闪络的影响[J]. 中国电机工程学报, 2016, 36(22): 6294-6302.
Liang Ying, Jin Zhe, Zhang Juncheng.Influence of surface charge on surface flashover of silicone rubber at different corona aging time[J]. Proceedings of the CSEE, 2016, 36(22): 6294-6302.
[13] 王有元, 刘玉, 王施又, 等. 电热老化对干式变压器中环氧树脂特性的影响[J]. 电工技术学报, 2018, 33(16): 3906-3916.
Wang Youyuan, Liu Yu, Wang Shiyou, et al.The effect of electrothermal aging on the properties of epoxy resin in dry-type transformer[J]. Transactions of China Electrotechnical Society, 2018, 33(16): 3906-3916.
[14] 梁虎成, 王雨帆, 杜伯学, 等. 表层非线性电导盆式绝缘子表面电荷分布与沿面放电特性[J]. 中国电机工程学报, 2022, 42(2): 835-844.
Liang Hucheng, Wang Yufan, Du Boxue, et al.Surface charge distribution and discharge behaviors of basin spacer with surface nonlinear conductivity[J]. Proceedings of the CSEE, 2022, 42(2): 835-844.
[15] 俞天波, 徐林峰, 潘必超. 干式变压器环氧树脂热老化特性分析[J]. 机械管理开发, 2023, 38(12): 56-57.
Yu Tianbo, Xu Linfeng, Pan Bichao.Analysis of thermal aging characteristics of epoxy resin for dry-type transformers[J]. Mechanical Management and Development, 2023, 38(12): 56-57.
[16] Yuan Ruijun, Li Han, Zhou Wenjun, et al.Study of compatibility between epoxy resin and C₄F₇N/CO₂ based on thermal ageing[J]. IEEE Access, 2020, 8: 119544-119553.
[17] Song Xinxin, Tan Zhenyu, Chen Bo.Study on the characteristics of atmospheric dielectric barrier discharges in He-N₂ admixture[J]. IEEE Transactions on Plasma Science, 2012, 40(12): 3471-3475.
[18] Bourdon A, Pasko V P, Liu N Y, et al.Efficient models for photoionization produced by non-thermal gas discharges in air based on radiative transfer and the Helmholtz equations[J]. Plasma Sources Science and Technology, 2007, 16(3): 656-678.
[19] Kulikovsky A A.Positive streamer between parallel plate electrodes in atmospheric pressure air[J]. Journal of Physics D Applied Physics, 1997, 30(3): 441-450.
[20] Fang Zhu, Fouracre R A, Farish O.Investigations of surface charging of DC insulator spacers[C]// Proceedings of Conference on Electrical Insulation and Dielectric Phenomena, Millbrae, CA, USA, 1996: 149-152.
[21] Kumara S, Alam S, Hoque I R, et al.DC flashover characteristics of a polymeric insulator in presence of surface charges[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2012, 19(3): 1084-1090.
[22] Blaise G, Le Gressus C.Charging and flashover induced by surface polarization relaxation process[J]. Journal of Applied Physics, 1991, 69(9): 6334-6339.
[23] Lu B X, Sun H Y.The role of photoionization in negative corona discharge[J]. AIP Advances, 2016, 6(9): 095111.
[24] Pillai A S, Hackam R.Surface flashover of solid dielectric in vacuum[J]. Journal of Applied Physics, 1982, 53(4): 2983-2987.
[25] Bilal Iqbal Ayubi, 张黎, 徐黄宽, 等. 高频电应力下聚酰亚胺沿面放电演化特性[J]. 电工技术学报, 2023, 38(5): 1177-1189.
Ayubi B I, Zhang Li, Xu Huangkuan, et al.Evolution characteristics of surface discharge along polyimide under high-frequency electric stress[J]. Transactions of China Electrotechnical Society, 2023, 38(5): 1177-1189.
[26] Plasma data exchange project[DB/OL]. (2019-01-23) [2024-04-30]. http://www.lxcat.laplace.univ-tlse.fr.
[27] Piquemal F, Kaja K, Chrétien P, et al.A multi-resistance wide-range calibration sample for conductive probe atomic force microscopy measurements[J]. Beilstein Journal of Nanotechnology, 2023, 14: 1141-1148.
[28] Dervos C, Bourkas P D, Kayafas E A, et al.Enhanced partial discharges due to temperature increase in the combined system of a solid-liquid dielectric[J]. IEEE Transactions on Electrical Insulation, 1990, 25(3): 469-474.
[29] 刘凯, 张鹏鹏, 高波, 等. ZnO@PS粒子分散特性及改性乙丙橡胶绝缘性能研究[J]. 电工技术学报, 2023, 38(8): 2265-2276.
Liu Kai, Zhang Pengpeng, Gao Bo, et al.Research on the dispersion characteristics of ZnO@PS particles and the insulation characteristics of modified ethylene propylene rubber[J]. Transactions of China Electro-technical Society, 2023, 38(8): 2265-2276.
[30] 宋岩泽, 梁贵书, 冉慧娟, 等. 等离子体处理调控表面电导率提高环氧树脂绝缘性能的研究[J]. 电工技术学报, 2023, 38(15): 3984-3998.
Song Yanze, Liang Guishu, Ran Huijuan, et al.Study on improving insulation properties of epoxy resin by regulating surface conductivity by plasma treatment[J]. Transactions of China Electrotechnical Society, 2023, 38(15): 3984-3998.
[31] 李光茂, 杜钢, 周鸿铃, 等. 环氧树脂在湿热环境中的老化特性与失效机理[J]. 高压电器, 2022, 58(6): 87-92.
Li Guangmao, Du Gang, Zhou Hongling, et al.Aging characteristics and failure mechanism of epoxy resin in humid and hot environment[J]. High Voltage Apparatus, 2022, 58(6): 87-92.
[32] 郑殿春. 气体放电数值仿真方法[M]. 北京: 科学出版社, 2016.
[33] 张镱议, 赵梓炜, 刘捷丰, 等. 耐电晕聚酰亚胺薄膜研究进展[J]. 电工技术学报, 2023, 38(5): 1190-1205.
Zhang Yiyi, Zhao Ziwei, Liu Jiefeng, et al.Research progress of corona resistant polyimide films[J]. Transactions of China Electrotechnical Society, 2023, 38(5): 1190-1205.
[34] 陈刚, 黄正勇, 段瑜, 等. 基于不同油纸介电常数配比的油纸沿面放电仿真[J]. 电工技术学报, 2020, 35(增刊2): 620-628.
Chen Gang, Huang Zhengyong, Duan Yu, et al.Simulation of surface discharge based on the different ratio of dielectric constants of oil and papers[J]. Transactions of China Electrotechnical Society, 2020, 35(S2): 620-628.
[35] 马云飞, 章程, 李传扬, 等. 重频脉冲放电等离子体处理聚合物材料加快表面电荷消散的实验研究[J]. 中国电机工程学报, 2016, 36(6): 1731-1738.
Ma Yunfei, Zhang Cheng, Li Chuanyang, et al.Experimental study of accelerating surface charge dissipation on polymer treated by repetitively pulsed discharge plasmas[J]. Proceedings of the CSEE, 2016, 36(6): 1731-1738.
[36] 高宇, 王小芳, 李楠, 等. 聚合物绝缘材料载流子陷阱的表征方法及陷阱对绝缘击穿影响的研究进展[J]. 高电压技术, 2019, 45(7): 2219-2230.
Gao Yu, Wang Xiaofang, Li Nan, et al.Charac-terization method for carrier trap and the effect on insulation breakdown within polymer insulating materials: a review[J]. High Voltage Engineering, 2019, 45(7): 2219-2230.