Aging Characteristics of Transformer Oil-paper Insulation Under Continuous Lightning Impulses

被引：0
|
作者：
Cheng X. [1 ]
Tao X. [2 ]
Ye G. [1 ]
Chen J. [1 ]
Chang H. [1 ]
Li T. [3 ]
机构：
[1] National Demonstration Center for Experimental Electrical and Electronic Education, Yangtze University, Jingzhou
[2] China Electric Power Research Institute, Wuhan
[3] Jingzhou Power Supply Company, State Grid Hubei Electric Power Company, Jingzhou
来源：
Gaodianya Jishu/High Voltage Engineering | 2023年 / 49卷 / 05期
关键词：
continuous lightning impulses; oil-paper insulation; polarization and depolarization current; tensile strength; trap;
D O I：
10.13336/j.1003-6520.hve.20220879
中图分类号：
学科分类号：
摘要：
As climate becomes increasely warm, extreme weather with thunderstorms occurs frequently. Transformers are threatened by continuous lightning impulse voltage, which damages the oil-paper insulation and impairs the safe operation of transformers. In order to simulate the operation of transformers in extreme thunderstorm environments, a experimental platform of lightning impulses was built. Lightning impulses were applied to the oil-paper insulation model in different time. The influence of continuous lightning impulses on the aging characteristics of oil-paper insulation was studied. The polarization and depolarization current tests were performed on the samples with different number of lightning impulses. The micromorphology changes of insulation paper were observed by scanning electron microscopy. The tensile strength of each paper and the moisture content of the oil were measured. Subsequently, the effect of fiber structure on the strain of insulation paper was analyzed. Finally, the depolarizing trap density spectrum was obtained through the id(t)t−lnt curve. The change rules of trap level and density with aging degree were discussed. The results indicate that, with the increase in the number of applied lightning impulses, the deterioration degree of the fiber structure will increase and the stress maximum will decrease. The polarization/depolarization current and the depolarizing trap density curves of oil-paper insulation move upward. The peak value of depolarizing trap density curve and its peak time will increase. In the macroscopic view, the deterioration of the fiber structure of the insulation paper can be reflected by the decrease of the stress peak value. Under the effect of lightning impulses, the peak of depolarizing trap density curve and its peak time can be used as the aging characteristic quantity of oil-paper insulation. © 2023 Science Press. All rights reserved.
引用
收藏
页码：1958 / 1966
页数：8
相关论文
共 29 条
  • [11] HILL D J T, LE T T, DARVENIZA M, Et al., A study of degradation of cellulosic insulation materials in a power transformer. part 2: tensile strength of cellulose insulation paper, Polymer Degradation and Stability, 49, 3, pp. 429-435, (1995)
  • [12] GHONEIM S S M, TAHA I B M., A new approach of DGA interpretation technique for transformer fault diagnosis, International Journal of Electrical Power & Energy Systems, 81, pp. 265-274, (2016)
  • [13] ZHANG Mingze, MENG Fanhao, LIU Ji, Et al., Research on nonlinear characteristics for frequency domain dielectric response of transformer oil-paper insulation, Proceedings of the CSEE, pp. 1-12, (2022)
  • [14] LIU Ji, CHENG Weichao, ZHANG Mingze, Et al., Dielectric response evaluation method for multi-factor aging of converter transformer oil-paper insulation, High Voltage Engineering, 48, 5, pp. 1684-1694, (2022)
  • [15] LI Junhao, SI Wenrong, YAO Xiu, Et al., Study of polarization and depolarization current measurements for assessment of aging state of oil-paper insulated transformers, Chinese Journal of Scientific Instrument, 30, 12, pp. 2605-2611, (2009)
  • [16] FOFANA I, HEMMATJOU H, FARZANEH M., Low temperature and moisture effects on polarization and depolarization currents of oil-paper insulation, Electric Power Systems Research, 80, 1, pp. 91-97, (2010)
  • [17] HAO Jian, Study on time/frequency domain dielectric spectroscopy and space charge characteristics of transformer oil-paper insulation thermal aging, (2012)
  • [18] CAI Jinding, CHEN Hancheng, Aging diagnosis of oil-paper insulation based on trap density spectrum, High Voltage Engineering, 43, 8, pp. 2574-2581, (2017)
  • [19] High voltage test techniques-part 3: definitions and requirements for on-site testing: GB/T 16927.3—2010, (2011)
  • [20] WANG Lin, ZHANG Meiyun, YANG Bin, Et al., Preparation and properties of thermally conductive aramid nanofibers based insulating paper with boron nitrides, Polymer Materials Science & Engineering, 36, 8, pp. 42-50, (2020)
123