直流电缆用交联聚乙烯绝缘的击穿概率及其尺度效应仿真

doi:10.19595/j.cnki.1000-6753.tces.222098

摘要
图/表
参考文献
相关文章 (15)

全文: PDF (1449 KB)
输出: BibTeX | EndNote (RIS)

摘要

电力电缆在远距离大容量电力传输和海上风电并网中起着极其重要的作用。受直流电场影响,交联聚乙烯（cross-linked polyethylene, XLPE）电缆存在着空间电荷积聚和电荷能量积累现象,导致绝缘材料被击穿而引发故障。该文建立了电荷输运与分子链位移击穿模型,对XLPE介质中载流子输运和能量积累过程进行了仿真,得到了XLPE特征击穿场强-试样厚度依赖特性以及击穿概率分布。仿真结果表明,XLPE直流击穿场强受尺度效应影响明显,击穿场强随着试样厚度增加而减少,且击穿强度概率计算结果服从威布尔分布。建立了电荷输运随机变量参数分散性与击穿概率分布的定量关系。随着试样厚度的增加,绝缘材料内部的缺陷分散性增加,电荷输运随机变量参数高斯分布中的方差增加,击穿威布尔分布形状参数减小。陷阱能级是影响击穿威布尔分布形状参数的最关键因素。该研究为电力电缆的优化设计和可靠性评估提供了仿真技术支撑。

	服务

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	朱敏慧
	闵道敏
	高梓巍
	武庆周

关键词 ：交联聚乙烯, 空间电荷, 威布尔分布, 尺度效应, 陷阱能级

Abstract：

Power cables play an extremely important role in long-distance high-capacity power transmission and offshore wind power grid connection. Affected by DC electric field, cross-linked polyethylene (XLPE) cables are subject to space charge accumulation and charge energy accumulation phenomena, leading to breakdown of insulation materials and causing faults. According to the solid dielectric scale effect principle, increasing the thickness or area of the specimen will result in an increase in volume and an increase in the probability of local defects, causing the breakdown field strength to decrease. However, the relationship between the variation of microscopic defect parameters of insulation materials with specimen thickness and its quantitative relationship on the breakdown probability has not been clarified. To address these issues, this paper proposes a charge transport and molecular displacement modulated model (CTMD), which investigates the relationship between the characteristic breakdown field and specimen thickness dependence of XLPE and the probability distribution of breakdown field by investigating the carrier transport and energy accumulation processes in the dielectrics.
The electrodes inject holes and electrons into the bulk of materials when a ramp voltage is applied to the insulating materials. Under the influence of the electric field, these carriers move into the insulating materials. Deep traps are formed at the interfaces of the crystalline/amorphous zone, the interface between spherical crystals, and by the polar groups in XLPE. The deep traps trap holes and electrons, causing distortions in the electric field due to space charge accumulation. Also, as the trapped charges are being affected by Coulomb forces, the expansion of the free volume due to molecular chain displacement raises the charge energy that is travelling inside it. The local current surges and the insulating material is broken through when the charge energy builds up to the point where it can cross the trap potential barrier. The findings demonstrate that the scale effect has a substantial impact on the DC breakdown field of XLPE. The breakdown field decreases with increasing specimen thickness, and the results of the breakdown strength probability calculation follow the Weibull distribution. Additionally, the breakdown probability distribution of XLPE can be modelled by adding random variables to CTMD. Altering the variance of the charge transport random variable controls the breakdown Weibull distribution's shape parameter. The shape parameter of the breakdown Weibull distribution decreases to 10.12, 5.76, 5.49, 5.36, and 4.34, as the specimen thickness increases from 50 μm to 250 μm. The Weibull distribution is most significantly influenced by the trap level, as seen by the fact that the value of the shape distribution parameter varies the fastest with the variation of the trap level.
The following conclusions are obtained from the simulations: (1) A correlation is established between the long-range motion of molecular chains under the action of Coulomb forces and the thickness dependence of the breakdown field of XLPE. The molecular chains containing trap charges have more time to undergo long-range motion under the electric field as the specimen thickens, and the free volume increases. At a lower electric field, the charges gain enough energy in the free volume to cause insulation material breakdown. (2) In the CTMD model, the probability distribution of the breakdown field obtained from the simulation obeys the Weibull distribution. Comparing the variation of the dispersion of different parameters with the thickness of the insulation material, it is found that the trap level is the most critical influencing factor of the shape parameter of the breakdown Weibull distribution. (3) As the specimen thickness increases, the variance in the Gaussian distribution of the charge transport random variable parameters gradually increases, the shape parameter of the breakdown Weibull distribution gradually becomes smaller, and the dispersion of defects inside the insulating material increases substantially.

Key words： XLPE space charge Weibull distribution size effect trap level

收稿日期: 2022-11-06

PACS:

TM85

基金资助:

国家自然科学基金面上项目（52077162）和国家自然科学基金委员会与中国工程物理研究院联合基金项目（U1830131）,以及电力设备电气绝缘国家重点实验室项目（EIPE22301）资助

通讯作者: 闵道敏男,1985年生,副教授,博士生导师,研究方向为先进绝缘材料与技术,高储能密度复合电介质,多物理场高效计算,局部放电、击穿、沿面闪络建模仿真与性能提升方法。E-mail：forrestmin@xjtu.edu.cn

作者简介: 朱敏慧女,1999年生,硕士研究生,研究方向为纳米复合电介质的介电、击穿性能,纳米复合电介质的多物理仿真方面。E-mail：zzzminhui@stu.xjtu.edu.cn

引用本文:

朱敏慧, 闵道敏, 高梓巍, 武庆周. 直流电缆用交联聚乙烯绝缘的击穿概率及其尺度效应仿真[J]. 电工技术学报, 0, (): 122-122. Zhu Minhui, Min Daomin, Gao Ziwei, Wu Qingzhou. Breakdown Probability and Size Effect Simulation of XLPE Insulation for DC Power Cables. Transactions of China Electrotechnical Society, 0, (): 122-122.

链接本文:

https://dgjsxb.ces-transaction.com/CN/10.19595/j.cnki.1000-6753.tces.222098 https://dgjsxb.ces-transaction.com/CN/Y0/V/I/122

[1] 杜伯学, 李忠磊, 杨卓然, 等. 高压直流交联聚乙烯电缆应用与研究进展[J]. 高电压技术,2017, 43(02): 344-354.
Du Boxue, Li Zhonglei, Yang Zhuoran,et al.Application and Research Progress of HVDC XLPE Cables[J]. High Voltage Engineering,2017, 43(02): 344-354.
[2] 邵森安, 马勰, 丰如男, 等. 海底电缆国内外研究综述[J]. 南方电网技术,2020, 14(11): 81-88.
Shao Sen'an, Ma Xie, Feng Runan,et al. Review of Researches on Submarine Cables at Home and Abroad[J]. Southern Power System Technology,2020, 14(11): 81-88.
[3] 王昊月, 李成榕, 王伟, 等. 高压频域介电谱诊断XLPE电缆局部绝缘老化缺陷的研究[J]. 电工技术学报,2022, 37(06): 1542-1553.
Wang Haoyue, Li Chengrong, Wang Wei,et al.Local Aging Diagnosis of XLPE Cables Using High Voltage Frequency Domain Dielectric Spectroscopy[J]. Transactions of China Electrotechnical Society,2022, 37(06): 1542-1553.
[4] 杜伯学, 韩晨磊, 李进, 等. 高压直流电缆聚乙烯绝缘材料研究现状[J]. 电工技术学报,2019, 34(01): 179-191.
Du Boxue, Han Chenlei, Li Jin,et al.Research status of polyethylene insulation material for HVDC cable[J]. Transactions of China Electrotechnical Society,2019, 34(01): 179-191.
[5] 刘云鹏, 刘贺晨, 高丽娟, 等. 电声脉冲法研究热老化对160kV直流电缆绝缘材料陷阱特性的影响[J]. 电工技术学报,2016, 31(24): 105-112.
Liu Yunpeng, Liu Hechen, Gao Lijuan,et al.Influence of Thermal Stress on the Traps Energy Properties of 160kV HVDC Cable Insulation Material Based on Pulsed Electro-Acoustic Method[J]. Transactions of China Electrotechnical Society,2016, 31(24): 105-112.
[6] 李国倡, 王家兴, 魏艳慧, 等. 高压直流电缆附件XLPE/SIR材料特性及界面电荷积聚对电场分布的影响[J]. 电工技术学报,2021, 36(14): 3081-3089.
Li Guochang, Wang Jiaxing, Wei Yanhui,et al.Effect of Material Properties of XLPE/SIR and Interface Charge Accumulation on Electric Field Distribution of HVDC Cable Accessory[J]. Transactions of China Electrotechnical Society,2021, 36(14): 3081-3089.
[7] 钱恺羽. 柔性直流输电用直流电缆绝缘击穿场强的尺寸效应研究[D]. 上海: 上海交通大学, 2018.
[8] Min Daomin, Yan Chenyu, Mi Rui,et al.Carrier Transport and Molecular Displacement Modulated dc Electrical Breakdown of Polypropylene Nanocomposites[J]. Polymers, 2018, 10(11):1207.
[9] Min Daomin, Li Shengtao, Ohki Yoshimichi.Numerical simulation on molecular displacement and DC breakdown of LDPE[J]. IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION, 2016, 23(1):507-516.
[10] Min Daomin, Li Yuwei, Yan Chenyu,et al.Thickness-Dependent DC Electrical Breakdown of Polyimide Modulated by Charge Transport and Molecular Displacement[J]. Polymers, 2018, 10(9).
[11] Ma Zhipeng, Yang Lijun, Bhutta M.S.,et al. Effect of Thickness on the Space Charge Behavior and DC Breakdown Strength of Cross-Linked Polyethylene Insulation[J]. IEEE Access, 2020, 8:85552-85566.
[12] Bhutta M.S., Yang Lijun, Ma Zhipeng,et al. Simulation of thickness controlled DC breakdown of XLPE regulated by space charge & molecular chain movement[J]. IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION, 2020, 27(4):1143-1151.
[13] 刘英, 王乐, 王磊, 等. 从缺陷影响看高压XLPE电缆绝缘减薄的必要性[J]. 高电压技术,2006,(07): 29-32.
Liu Ying, Wang Le, Wang Lei,et al. Necessity of Reducing the Insulati on Thickness of HV XLPE Cables from the Defect Point of View[J].2006,07): 29-32.
[14] 蔡姝娆, 高梓巍, 纪民尊, 等. 聚丙烯载流子输运与能量积累调制直流击穿威布尔分布特性仿真研究[J]. 电气工程学报,2021, 16(02): 50-59.
Cai Shurao, Gao Ziwei, Ji Minzun,et al.Simulation of Carrier Transport and Energy Accumulation Modulated DC Breakdown Weibull Distribution in Polypropylene[J]. Journal of Electrical Engineering,2021, 16(02): 50-59.
[15] Hoang A.T., Serdyuk Y. V., Gubanski S. M. Charge Transport in LDPE Nanocomposites Part II-Computational Approach[J]. Polymers, 2016, 8(4).
[16] Kuik M., Koster L.J. A., Wetzelaer G. A. H.,et al. Trap-Assisted Recombination in Disordered Organic Semiconductors[J]. PHYSICAL REVIEW LETTERS, 2011, 107(25).
[17] Le Roy S., Segur P., Teyssedre G.,et al.Description of bipolar charge transport in polyethylene using a fluid model with a constant mobility: model prediction[J]. JOURNAL OF PHYSICS D-APPLIED PHYSICS, 2004, 37(2):298-305.
[18] Shockley W., Read WT.Statistics of the Recombinations of Holes and Electrons[J]. Physical Review, 1952, 87(5):835-842.
[19] van der Holst J. J. M., van Oost F. W. A., Coehoorn R.,et al. Electron-hole recombination in disordered organic semiconductors: Validity of the Langevin formula[J]. PHYSICAL REVIEW B, 2009, 80(23).
[20] Kuik M., Koster L.J. A., Dijkstra A. G.,et al. Non-radiative recombination losses in polymer light-emitting diodes[J]. ORGANIC ELECTRONICS, 2012, 13(6):969-974.
[21] 陈季丹等. 电介质物理学[M]. 机械工业出版社, 1982.
[22] 苏鹏飞. 高压直流电缆用XLPE的直流击穿机理的实验研究[D]. 上海: 上海交通大学, 2020.