Influence of Temperature on Polarization and Depolarization Current of Oil-Paper Insulation
Ma Zhiqin1,2, Liao Ruijin2, Hao Jian3, Zhao Xiaoping4, Wang Yaolong4, Yang Lijun2
1.Electric Power Research Institute of Guangdong Power Grid Corporation, Guangzhou 510080 China; 2.State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing University, Chongqing 400044 China; 3.State Grid Chongqing Electric Power Co., Chongqing Electric Power Research Institute, Chongqing 401123 China; 4.Yunnan Electric Power Research Institute(Group)Co., Ltd., Kunming 650051 China
Abstract:Temperature is one of the most crucial factors that influence the field measurement results of dielectric response method. For research the influence of temperature on polarization and depolarization current, oil paper samples are made according to the structure of transformer winding. Polarization and depolarization currents of oil paper samples are measured at different temperatures. A new method is put forward to eliminate the influence of temperature. Results show that both the polarization and depolarization current increase with temperature. Polarization and depolarization current decrease with time and become constant finally. An inflection point appears in the depolarization current and the time of inflection point shifts to lower with temperature increasing. A master curve can be formed by shifting the polarization and depolarization currents measured at different temperatures, and the temperature impact on the polarization and depolarization current can be solved by using the time-shift factor and amplitude-shift factor. Both the time-shift factor and amplitude-shift factor meet the Arrhenius equation, and the activation energy of oil paper samples solved by these two factors are almost the same, approximate 61kJ/mol.
马志钦, 廖瑞金, 郝建, 赵小平, 王耀龙, 杨丽君. 温度对油纸绝缘极化去极化电流的影响[J]. 电工技术学报, 2014, 29(4): 290-297.
Ma Zhiqin, Liao Ruijin, Hao Jian, Zhao Xiaoping, Wang Yaolong, Yang Lijun. Influence of Temperature on Polarization and Depolarization Current of Oil-Paper Insulation. Transactions of China Electrotechnical Society, 2014, 29(4): 290-297.
[1] 廖瑞金, 杨丽君, 孙才新, 等. 基于局部放电主成分因子向量的油纸绝缘老化状态统计分析[J]. 中国电机工程学报, 2006, 26(14): 114-119. Liao Ruijin, Yang Lijun, Sun Caixin, et al. Aging condition assessment of oil-paper based on principal component and factor analysis of partial discharge[J]. Proceedings of the CSEE, 2006, 26(14): 114-119. [2] 岂小梅. 变压器绕组变形的综合判断及经验总结[J]. 电网技术, 2006, 30(增刊): 220-222. Qi Xiaomei. Synthetic diagnosis and experience about winding deformation of transformer[J]. Power System Technology, 2006, 30(Sup.): 220-222. [3] 速水敏幸. 电力设备的绝缘诊断[M]. 北京: 科学出版社, 2003. [4] 廖瑞金, 梁帅伟, 周天春, 等. 天然酯-纸绝缘热老化速度减缓及其原因分析[J]. 电工技术学报, 2008, 23(9): 32-37. Liao Ruijin, Liang Shuaiwei, Zhou Tianchun, et al. Comparison for the mineral oil-paper and the nature ester-paper insulation degradation and cause analysis[J]. Transactions of China Electrotechnical Society, 2008, 23(9): 32-37. [5] 路长柏. 电力变压器绝缘技术[M]. 黑龙江: 哈尔滨工业大学出版社, 1997. [6] Sans J R, Bilgin K M, Kelly J, et al. Large scale survey of frantic compounds in operating transformers and implications for estimating service life[C]. IEEE International Symposium on Electrical Insulation, Arlington, USA, 1998: 232-239. [7] Hill D J, T T Le, Darveniza M, et al. A study of degradation of cellulosic insulation materials in a power transformer, part 2. Tensile strength of cellulose insulation paper[J]. Polymer Degradation and Stability, 1995, 49(3): 429-435. [8] 杨丽君, 廖瑞金, 孙会刚, 等. 变压器油纸绝缘热老化特性及特征量研究[J]. 电工技术学报, 2009, 24(8): 27-33. Yang Lijun, Liao Ruijin, Sun Huigang, et al. Investigation on properties and characteristics of oil-paper insulation in transformer during thermal degradation process[J]. Transactions of China Electrotechnical Society, 2009, 24(8): 27-33. [9] Ekanayake Chandima, Stanislaw M. Application of dielectric spectroscopy measurements for estimating moisture content in power transformers[J]. KIEE International Transactions on Electrophysics and Application, 2004, 4-C(3) : 81-90. [10] Kuang Y C, Chen G, Jarmm P. Recovery voltage measurement on oil-paper insulation with simple geometry and controlled environment[C]. IEEE International Conference on Solid Dielectrics, Toulouse, France, 2004: 1-9. [11] Saha T K, Purkait P. Investigation of polarization and depolarization current measurements for the assessment of oil-paper insulation of aged transformers[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2004, 11(1): 144-154. [12] Yew J H, Pradhan M K, Saha T K. Effects of moisture and temperature on the frequency domain spectroscopy analysis of power transformer insulation[C]. IEEE Power Engineering Society General Meeting, Pittsburgh, USA, 2008: 42-48. [13] Yew J H, Saha T K, Thomas A J. Impact of temperature on the frequency domain dielectric spectroscopy for the diagnosis of power transformer insulation[C]. IEEE Power Engineering Society General Meeting, Montreal, Canada, 2006: 209-231. [14] Wolny Stefan. The Influence of temperature and dampness on the value of the main time constant of paper-oil insulation determined by using Deby’s model[J]. Physics and Chemistry Solid State, 2006, 7(3): 572-576. [15] Saha T K, Purkait P. Investigations of temperature effects on the dielectric response measurements of transformer oil-paper insulation system[J]. IEEE Transactions on Power Delivery, 2008, 23(1): 252-260. [16] Koch Maik, Tenbohlen Stefan. Diagnostics of oil paper insulations using relaxation currents[C]. Proceedings of the 14th International Symposium on High Voltage Engineering, Beijing, China, 2005: 112-121. [17] Fofana I, Hemmatjou H, Meghnefi F. Effect of thermal transient on the polarization and depolarization current measurements of oil-paper insulation[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2011, 18(2): 513-520. [18] Seytashmehr A, Fofana I, Eichler C, et al. Dielectric spectroscopic measurements on transformer oil-paper insulation under controlled laboratory conditions[J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2008, 15(4): 1100-1111. [19] Saha T K, Purkait P. Understanding the impacts of moisture and thermal ageing on transformer’s insulation by dielectric response and molecular weight measurements[J]. IEEE Transaction on Dielectrics and Electrical Insulation, 2008, 15(2): 568-582. [20] Provencher H, Noirhomme B, David E. Effect of aging on the dielectric properties of insulation paper of power transformers[C]. IEEE Electrical Insulation Conference, Montreal, Canada, 2009: 473-477. [21] Saha T K, Purkait P. Understanding the impacts of moisture and thermal ageing on transformer’s insulation by dielectric response and molecular weight measurements[J]. IEEE Transactions on Dielectric and Electrical Insulation, 2008, 15(2): 568-582. [22] Ekanayake Chandima. Diagnosis of moisture in transformer insulation-application of frequency domain spectroscopy[D]. Sweden: Chalmers University of Technology, 2006. [23] CIGRÉ Task Force 15. 01. 09. Dielectric response methods for diagnostics of power transformers[J]. IEEE Electrical Insulation Magazine, 2003, 19(3): 12-18. [24] Saha T K, Purkait P, Müller F. Deriving an equivalent circuit of transformers insulation for understanding the dielectric response measurements[J]. IEEE Transactions on Power Delivery, 2005, 20(1): 149-157. [25] Jonscher A K. Dielectirc relaxation in solids[M]. London, U. K. : Chelsea Dielectrics Press Limited, 1996. [26] Ohlen Matz, Werelius Peter. Dielectric frequency response and temperature dependence of power factor [C]. IEEE International Symposium on Electrical Insulation, San Diego, USA, 2010: 55-62.