Electric Field Characteristics and Charge Motion Model in Transformer Oil Under Impulse Voltage

被引：0
|
作者：
Qi B. [1 ]
Zhao X. [2 ]
Zhang S. [2 ]
Yuan Q. [1 ]
Gao C. [1 ]
Li C. [1 ]
机构：
[1] State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources (North China Electric Power University), Changping District, Beijing
[2] China Electric Power Research Institute, Haidian District, Beijing
来源：
| 1600年 / Chinese Society for Electrical Engineering卷 / 37期
关键词：
Charge motion mode; Electrode material; Impulse voltage; Kerr effect; Spatial position; Transform oil; Voltage amplitude; Wave head time;
D O I：
10.13334/j.0258-8013.pcsee.171148
中图分类号：
学科分类号：
摘要：
The design of the insulation structure of the transformers under impulse voltage mainly relies on the simulating analyzation but lacks the experimental verification to value the effect of charge on electric field. The characteristics of electric field in transformer oil under impulse voltage were carried out from 4 aspects, including electrode material, voltage amplitude, wave head time and space distribution. The results show that the aluminum electrode has the largest amount of charge injection, followed by stainless steel and the smallest one belongs to brass electrode, which is caused by the different work function of Al, Fe and Cu. With the increase of the voltage amplitude, the effect of space charge on the electric field in the oil gap is enhanced first, then weakened and then enhanced; As the wave head time prolongs, the electric field peak value in oil decreases gradually, a 17.6% reduction occurs from 500ns to 40μs, which is probably due to the larger charge injection quantity and the corresponding stronger weakening effect. In the process of impulse voltage, there exists a dynamic process for charges, namely the different effect of charges on electric field caused by the charge position varying with time. The time for the negative charges to move from the cathode to anode is 278ns, and the average velocity is 1.1×10-3m2/(V⋅s), requiring at least 2μs to reach the relatively stable state. On the basis of experimental results, a charge motion model in transformer oil under impulse voltage was proposed, in that the field emission theory and ionization theory were applied to elucidate the sources and motion mechanisms for positive and negative charges. © 2017 Chin. Soc. for Elec. Eng.
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页码：218 / 229
页数：11
相关论文
共 20 条
  • [1] Liu Z., Guo X., Insulation Structure of UHV Power Transformer, High Voltage Engineering, 36, 1, pp. 7-12, (2010)
  • [2] Liu D., Zhang H., Zhao L., Et al., Homemade core technology of 750kV transformer outlet device, Transactions of China Electrotechnical Society, 26, 2, pp. 88-93, (2011)
  • [3] Li G., Wang X., Li P., Et al., Insulation level and test technology of 1000kV power transformers, Power System Technology, 32, 3, (2008)
  • [4] Cassidy E.C., Hebner R.E., Zahn M., Et al., Kerr-effect studies of an insulating liquid under varied high-voltage conditions, IEEE Transactions on Electrical Insulation, EI-9, 2, pp. 43-56, (1974)
  • [5] Zahn M., Ohki Y., Rhoads K., Et al., Electro-optic charge injection and tramsport measurements in highly purified water and water/ethylene glycol mixtures, IEEE Transactions on Electrical Insulation, 20, 2, pp. 199-211, (1985)
  • [6] Helgeson A., Zahn M., Kerr electro-optic measurements of space charge effects in HV pulsed propylene carbonate, IEEE Transactions on Dielectrics and Electrical Insulation, 9, 5, pp. 838-844, (2002)
  • [7] O'Sullivan F., Modeling the effect of ionic dissociation on charge transport in transformer oil, 2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena, pp. 756-759, (2006)
  • [8] Sima W., Shi J., Yang Q., Et al., Space charge injection and transport in propylene carbonate under switching impulse voltage, Proceedings of the CSEE, 34, 36, pp. 6568-6577, (2014)
  • [9] Qi B., Zhao X., Li C., Methods to reduce errors for DC electric field measurement in oil-pressboard insulation based on Kerr-effect, IEEE Transactions on Dielectrics and Electrical Insulation, 23, 3, pp. 1675-1682, (2016)
  • [10] Qi B., Zhao X., Li C., Et al., Electric field distribution in oil-pressboard insulation under AC-DC combined voltages, IEEE Transactions on Dielectrics and Electrical Insulation, 23, 4, pp. 1935-1941, (2016)
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