Discharge Development and Characteristics of Oil-immersed Pressboard Surface with Different Moisture Contents
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摘要: 电力变压器内部水分增加将严重影响油纸绝缘性能，导致绝缘纸板表面更容易出现沿面放电故障. 为了研究交流电压下不同水分含量绝缘纸板的沿面放电特性，建立了典型的针板沿面放电模型. 基于脉冲电流法实时测量沿面放电模型的放电特征图谱，同时采用高速相机记录绝缘纸板上白斑形成和发展过程. 分析了不同水分含量纸板起始放电电压和闪络电压的变化趋势，以及沿面放电特征参数变化趋势. 分析结果表明：纸板含水量的增加导致起始放电电压显著降低；不同水分含量纸板的沿面放电和白斑形成发展过程均可划分为4个阶段，沿面放电过程和白斑形成发展的4个阶段存在一一对应关系；通过观察分析绝缘纸板微观结构，发现试验后的纸板纤维严重断裂，且纸板中水分含量越高，纸板表面受损害越严重，纸板含水量从小于0.5%增加到3.8%时，起始放电电压下降了61.3%.Abstract: The increase of moisture content in power transformer will seriously affect the insulation performance of oil-paper, more easily resulting in the surface discharge fault of insulated pressboard. In order to study the discharge characteristics of insulated pressboard with different moisture contents under AC condition, a typical model of needle board surface discharge was established. Based on the pulse current method, the characteristic charts of the surface discharge model were measured in real time, and a high-speed camera was used to record the formation and development of white mark on insulated pressboard. The variation trend of initial discharge voltage and flashover voltage under different moisture contents of pressboard was analyzed, and then that of the related discharge characteristic parameters was analyzed. The results show that the increase of moisture content in pressboard significantly reduces the onset voltage. The process of surface discharge and white mark formation and development on pressboard with different moisture contents can be divided into four stages. There is a one-to-one relationship between the four stages of surface discharge and white mark formation and development. By observing and analyzing the microstructure of insulated pressboard, it is found that the fibers of the pressboard were severely broken after tests. The higher the moisture content of the pressboard before tests, the more serious the damage to the surface of the pressboard. When the moisture content of pressboard increases from less than 0.5% to 3.8%, the initial discharge voltage decreases by 61.3%.
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Key words:
- surface discharge /
- moisture content /
- discharge characteristics /
- white mark /
- microstructure
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图 2 针板沿面放电模型结构图和实物图
Figure 2. Structure diagram and physical picture of needle board model
图 3 局部放电特征参数随电压变化情况
Figure 3. Relationship between partial discharge characteristics and supply voltage
图 4 针板沿面放电模型的局部放电四个阶段的PRPD图谱
Figure 4. PRPD patterns for four stages in needle board discharge model
图 5 绝缘纸板上白斑形成发展过程
Figure 5. Formation and development of white mark on pressboard surface
图 6 不同水分含量纸板试验后表面微观形貌（1 000倍放大）
Figure 6. Surface micrograph of pressboard with different water contents after tests (1 000 times)
表 1 处理后变压器油各项参数
Table 1. Parameters of transformer oil after filtering
属性 指标 实测值 试验标准 水分含量/
×10−6≤ 30 14 GB/T 7600—2014 击穿电压/kV ≥ 30 71 GB/T 507—2002 介质损耗 ≤ 0.005 0 0.000 8 GB/T 5654—2007 界面张力/
（mN•m−1）≥ 40 46 GB/T 6541—1986 酸值/（mg•g−1） ≤ 0.010 0 0.007 NB/SH/T 0836—2010 
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表 2 纸板水分含量对起始放电电压和闪络电压的影响
Table 2. Effect of moisture content in pressboard on initial discharge voltage and flashover voltage
水分含量/% 起始放电电压/kV 闪络电压/kV 平均值 标准差 平均值 标准差 < 0.5 31 1.91 63 0.48 1.1 28 1.41 61 0.98 1.5 23 2.33 59 0.33 1.9 17 1.77 58 0.47 2.4 14 1.64 57 0.28 3.8 12 2.63 57 0.44
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表 3 不同电压下纸板中水分含量对放电功率的影响
Table 3. Effect of moisture content in pressboard on discharge power under different voltages
电压/kV 水分含量/% 放电功率/nW 15 < 0.5 0 1.1 0 1.5 0 1.9 0 2.4 0 3.8 467 25 < 0.5 0 1.1 0 1.5 0 1.9 1 221 2.4 1 954 3.8 2 650 35 < 0.5 10 412 1.1 12 530 1.5 15 460 1.9 17 235 2.4 20 645 3.8 21 930
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YI X, WANG Z D. Surface tracking on pressboard in natural and synthetic transformer liquids under ac stress[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2013, 20(5): 1625-1634. doi: 10.1109/TDEI.2013.6633692 潘臻,牛炜. 变压器油纸绝缘老化光谱分析新特征量研究[J]. 电气技术,2014(9): 16-23. doi: 10.3969/j.issn.1673-3800.2014.09.004PAN Zhen, NIU Wei. Study on new characteristic quantities of spectral analysis of transformer oil paper insulation aging[J]. Electrical Technology, 2014(9): 16-23. doi: 10.3969/j.issn.1673-3800.2014.09.004 郭洪英. 基于回复电压极化谱小波包变换的变压器绝缘老化诊断方法[J]. 电力系统保护与控制,2016,44(24): 170-175. doi: 10.7667/PSPC160836GUO Hongying. Diagnostic method of transformer insulation aging based on wavelet packet transform of polarization spectrum of voltage response[J]. Protection and control of power system, 2016, 44(24): 170-175. doi: 10.7667/PSPC160836 吴广宁,夏国强,宋臻杰,等. 基于小波分析和时域介电谱的变压器油纸绝缘老化状态评估[J]. 高电压技术,2018,44(1): 226-233.WU Guangning, XIA Guoqiang, SONG Zhenjie, et al. Status assessment of aging condition of transformer oil-paper insulation based on time domain dielectric spectroscopy and wavelet analysis[J]. High Voltage Engineering, 2018, 44(1): 226-233. DAI J, WANG Z D, JARMAN P. Creepage discharge on insulation barriers in aged power transformers[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2010, 17(4): 1327-1335. doi: 10.1109/TDEI.2010.5539705 LUNDGAARD L, LINHJELL D, BERG G, et al. Propagation of positive and negative streamers in oil with and without pressboard interfaces[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 1998, 5(3): 388-395. doi: 10.1109/94.689428 NAKAO Y, NARUSE M, SUZUKI Y, et al. Influence of insulating barrier on the creepage discharge in transformer oil[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 1997, 4(6): 775-779. doi: 10.1109/94.654703 高敏华,伍志荣,付锡年,等. 含水量对换流变压器绝缘性能的影响[J]. 变压器,2014,51(10): 21-25.GAO Minhua, WU Zhirong, FU Xinian, et al. Effect of water content on insulation performance of converter transformer[J]. Transformer, 2014, 51(10): 21-25. 刘海丽. 含水率对复合电场下油纸绝缘介电性能影响的研究[D]. 哈尔滨: 哈尔滨理工大学, 2014. 李群,赵宇民,金元,等. 基于水分含量的油纸绝缘气隙缺陷放电特性研究[J]. 变压器,2018,55(12): 58-62.LI Qun, ZHAO Yumin, JIN Yuan, et al. Study on discharge characteristics of air gap defects in oil-paper insulation based on moisture content[J]. Transformer, 2018, 55(12): 58-62. 李熙宁,汲胜昌,崔彦捷,等. 水分对交直流复合电压下油纸绝缘沿面放电特性影响研究[J]. 高压电器,2018,54(11): 184-193.LI Xining, JI Shengchang, CUI Yanjie, et al. Study on the effect of water on the discharge characteristics along oil-paper insulation under AC/DC composite voltage[J]. High Voltage Electrical Appliances, 2018, 54(11): 184-193. 刘青松,邓军,池明赫,等. 水分对复合电场下油纸绝缘局部放电特性的影响[J]. 哈尔滨理工大学学报,2018,23(6): 82-87.LIU Qingsong, DENG Jun, CHI Minghe, et al. Effects of water on partial discharge characteristics of oil-paper insulation under composite electric field[J]. Journal of Harbin University of Technology, 2018, 23(6): 82-87. 陈庆国,池明赫,王刚,等. 含水率对复合电场下油纸绝缘电场分布的影响[J]. 电机与控制学报,2013,17(7): 54-60. doi: 10.3969/j.issn.1007-449X.2013.07.009CHEN Qingguo, CHI Minghe, WANG Gang, et al. Effect of water content on electric field distribution of oil-paper insulation under composite electric field[J]. Journal of Electrical Machinery and Control, 2013, 17(7): 54-60. doi: 10.3969/j.issn.1007-449X.2013.07.009 NAKAO Y, MOURI A, ITOOKA T, et al. Propagation of creepage discharge on solid insulator in insulating oil[C]//Proceedings of 1999 IEEE 13th International Conference on Dielectric Liquids. Nara: IEEE, 1999: 257-260. RUSHALL R T. Dielectric properties of oil-Soaked pressboard as affected by water[J]. Proceedings of the IEE-Part I:Insulating Materials, 1953, 100(3): 81-88. doi: 10.1049/pi-2a.1953.0014 KRAUSE C H, BRUPBACHER P, FEHLMANN A, et al. Moisture effects on the electric strength of oil/pressboard insulation used in power transformers[C]//IEEE International Conference on Dielectric Liquids, 2005. Coimbra: IEEE, 2005: 369-372. 中华人民共和国国家质量监督检验检疫总局. 局部放电测量: GB/T 7354—2003[S]. 北京: 中国标准出版社, 2004. 王伟,周冰,徐剑峰,等. 油纸绝缘系统中含高水分绝缘纸板的沿面爬电特性[J]. 高电压技术,2011,37(8): 1924-1929.WANG Wei, ZHOU Bing, XU Jianfeng, et al. Surface creep characteristics of high moisture insulated cardboard in oil-paper insulation system[J]. High Voltage Technology, 2011, 37(8): 1924-1929. ARALKELLIAN V G, FOFANA I. Water in oil-filled,high-voltage equipment,part I:states,aolubility,and equilibrium in insulating materials[J]. IEEE Electr. Insul. Mag., 2007, 23(4): 15-27. doi: 10.1109/MEI.2007.386480 USHAKOV V Y, KLIMKIN V F, KOROBEYNIKOV S M. Impulse breakdown of liquids[M]. Berlin: Springer, 2007. HARADA M, OHGA Y, WATANABE I, et al. Ionization energies for solvated polycyclic aromatic hydrocarbons[J]. Chemical Physics Letters, 1999, 303: 489-492. doi: 10.1016/S0009-2614(99)00277-8 李斯盟,李清泉,刘洪顺,等. 基于雷达谱图的交直流复合电压下油纸针板模型局放阶段识别[J]. 中国电机工程学报,2018,38(19): 5897-5908,5948.LI Simeng, LI Qingquan, LIU Hongshun, et al. Partial discharge phase recognition of oil-paper needle-board model under AC/DC compound voltage based on radar spectrogram[J]. Journal of Electrical Engineering of China, 2018, 38(19): 5897-5908,5948. 崔彦捷,彭平,曹沛,等. 针板电极下局部放电对油浸绝缘纸板表面的影响[J]. 西安交通大学学报,2017,51(4): 37-44.CUI Yanjie, PENG Ping, CAO Pei, et al. The effect of partial discharge under needle plate electrode on the surface of oil-immersed insulated cardboard[J]. Journal of Xi’an Jiaotong University, 2017, 51(4): 37-44. -
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