TiO_2纳米粒子对变压器油绝缘和电荷输运特性的影响
|
摘要
随着我国百万伏特高压等级电网的建设,电压等级的升高,对变压器油的品质将提出更高的要求。为了进一步提高变压器的绝缘水平,缩小变压器的尺寸,有效保障超大规模输电系统的安全稳定运行,迫切需要开发高绝缘强度的新型变压器油。目前,已有研究者将纳米粒子添加到变压器油中改善其绝缘特性。
关于纳米改性变压器油的研究中存在着一些尚未解决的问题,其中包括：①纳米改性变压器油的长期稳定性；②纳米粒子对电荷输运过程的影响机理。
本文利用两步法制备了具有良好分散稳定性的TiO2纳米粒子改性变压器油,油样室温静置18个月后仍透明澄清、未出现团聚现象,且静置前后纳米粒子的粒径均在20nm左右、分散均匀。对获得的具有长期稳定性的纳米改性变压器油进行了工频击穿、雷电冲击击穿和局部放电特性的测试,发现纳米粒子不仅可以使变压器油的工频和雷电击穿电压提高至未改性前的1.2倍,而且在雷电冲击电压下纳米改性变压器油中流注传播速度降低到纯油的65%。除此以外,纳米改性变压器油的局部放电起始电压为纯油的1.1倍,且长时间耐局部放电特性明显改善。
研究了TiO2纳米粒子对劣化(高水分、老化)变压器油绝缘特性的影响,发现随着变压器油劣化程度的加深,纳米粒子改性效果更加明显,工频击穿电压提高至纯油的2倍以上,而且可以有效抑制油中局部放电现象,局部放电起始电压为纯油的1.2倍。
采用电声脉冲法测量技术,研究了纳米粒子对变压器油(新油、劣化油)中电荷积累、消散特性的影响。在电荷积累特性研究中发现,随着施加压时间的延长,纯油(新油、劣化油)中电场发生了一定程度的畸变,其最大场强为平均场强的1.74倍,而纳米改性油中电场分布则较为均匀。在电荷消散特性研究中发现,纳米粒子可以使变压器油中电荷消散速率提高34%。利用ICCD高速相机对雷电冲击电压下变压器油改性前后的流注发展变化规律进行了研究,观察了纳米粒子对变压器油中流注发展形态的影响。
利用热刺激电流法探索了纳米粒子对变压器油(新油、劣化油)中陷阱分布的重构作用,通过对变压器油陷阱特性的测量发现,TiO2纳米粒子的添加使得变压器油中的浅陷阱密度达到了纯油2倍以上。通过Zeta电位的测量证实了纳米粒子与变压器油两相界面结构的存在和其性质的变化对变压器油中陷阱特性和电荷输运特性的影响。
在此基础上,提出了纳米改性变压器油的电荷传导浅陷阱理论：纳米粒子具有很大的比表面积,通过固体纳米粒子和液体介质分子间的相互作用,可以形成不同于本体材料的两相界面,导致了变压器油内部浅陷阱密度显著增大。在高场强区电离产生的电荷通过在浅陷阱间被反复捕获和释放的过程迅速迁移,提高了局部电导率,减少了流注前端的净电荷密度,避免了电荷在变压器油中的积累与电场畸变,从而抑制了变压器油中流注的发展速度。除此之外,电子通过在浅陷阱间反复捕获和释放的过程降低了其自身的碰撞能量,削弱了其对变压器油分子的电离,最终提高了变压器油的绝缘特性。
Transmission and distribution transformers form a critical, highly loaded and expensive part of the electricity generation and distribution network. Electric transformers rely on the high dielectric strength properties of insulating oil to achieve normal operation. Developing new transformer oil with excellent insulation properties means a lot to improve the safe operation level of transformer, and it is also very helpful to decrease the size and weight of ultra-high voltage transformer. Recently, many researches have been focused on the nano-modified transformer oil.
In the investigation of nano-modified transformer oil, there are some problems to be solved, among which are the long time stability of nanofluids and the effect of nanoparticle on the charge transport in nano-modified transformer oil.
In this dissertation, we aim to develop a new type of nanoparticle modified transformer oil-based nanofluids by suspending semiconductive nanoparticles TiO2into transformer oil, investigate their stability and insulating properties. It reveals that the nanofluid presented high colloidal stability, exhibiting no sedimentation after18months at room temperature (average particle size20nm). Semiconductive nanoparticles can increase the ac and lightning impulse breakdown voltages of nanofluids up to more than1.2times compared with pure oils. Especially, the velocity of streamer in nanofluids is slowed down by65%of that in pure oil. Meanwhile, the partial discharge initiate voltage (PDIV) and resistance against PD of the modified oil was also dramatically improved.
In order to promote the practical application of nanofluids, the effect of nanoparticles on the insulation properties of transformer oil in the different humidity and aged conditions was investigated. It is shown that breakdown voltages of samples decrease significantly with deterioration increase. It is interesting to notice that the discrepancy of breakdown voltage between nanofluids and pure oil become more and more obvious with deterioration increase, indicating less reduction of electrical strength in nanofluids.
To understand breakdown phenomenon in the insulating materials, the distribution of space charge and the internal electric field has been considered as a key component, which can be assessed by the pulse electroacoustic technique (PEA). The effect of nanoparticles on charge accumulation, decay and transport processes in oil and nanofluid was investigated. The charges in oil are increasing with time and result in an increasing internal field, approximately174%of the applied field. However, the field in the nanofluids appears to be'evening out' and approximately the same as the applied field. It is found that the charge decay rate for nanofluids is much higher than that for pure oil after the voltage is removed. This rapid charge decay rate is mainly associated with TiO2nanoparticles in nanofluids and effectively prevents the distortion of electric field in the oil. The mode transition and the development of streamer were studied with an ICCD camera.
In order to investigate the relationship between charge transport and the trap characteristics, thermally stimulated current method (TSC) measurements were performed. It is believed that TSC measurements can be used to investigate the nature and origin of charge carrier traps in dielectrics, including the change of the number and energy of the trap sites. It is noted that shallower trap centers with higher trap density were formed in nanofluids. The trap density in nanofluid is almost2times compared with that in pure oil. According to the Electrophoresis measurements, it is verified that the internal interfaces between nanoparticles and oil induces alter local structure in the vicinity of the nanoparticles and give rise to altered trap characteristic.
Based on our measurement results, it is believed that the surface area in contact with the oil is dramatically increased and creates large interaction zones and the corresponding higher shallow trap density. The charge created at high field in the oil can be captured by the shallow traps and decay fast by the trapping and de-trapping process, which can reduce the the velocity and amplitude of electric field wave at the point of streamer. Meanwhile, facile charge movement induced by the trapping and de-trapping process can impair the ionization process caused by fast electrons and offer more uniform internal electric field and high dielectric strength of nanofluid.
关于纳米改性变压器油的研究中存在着一些尚未解决的问题,其中包括：①纳米改性变压器油的长期稳定性；②纳米粒子对电荷输运过程的影响机理。
本文利用两步法制备了具有良好分散稳定性的TiO2纳米粒子改性变压器油,油样室温静置18个月后仍透明澄清、未出现团聚现象,且静置前后纳米粒子的粒径均在20nm左右、分散均匀。对获得的具有长期稳定性的纳米改性变压器油进行了工频击穿、雷电冲击击穿和局部放电特性的测试,发现纳米粒子不仅可以使变压器油的工频和雷电击穿电压提高至未改性前的1.2倍,而且在雷电冲击电压下纳米改性变压器油中流注传播速度降低到纯油的65%。除此以外,纳米改性变压器油的局部放电起始电压为纯油的1.1倍,且长时间耐局部放电特性明显改善。
研究了TiO2纳米粒子对劣化(高水分、老化)变压器油绝缘特性的影响,发现随着变压器油劣化程度的加深,纳米粒子改性效果更加明显,工频击穿电压提高至纯油的2倍以上,而且可以有效抑制油中局部放电现象,局部放电起始电压为纯油的1.2倍。
采用电声脉冲法测量技术,研究了纳米粒子对变压器油(新油、劣化油)中电荷积累、消散特性的影响。在电荷积累特性研究中发现,随着施加压时间的延长,纯油(新油、劣化油)中电场发生了一定程度的畸变,其最大场强为平均场强的1.74倍,而纳米改性油中电场分布则较为均匀。在电荷消散特性研究中发现,纳米粒子可以使变压器油中电荷消散速率提高34%。利用ICCD高速相机对雷电冲击电压下变压器油改性前后的流注发展变化规律进行了研究,观察了纳米粒子对变压器油中流注发展形态的影响。
利用热刺激电流法探索了纳米粒子对变压器油(新油、劣化油)中陷阱分布的重构作用,通过对变压器油陷阱特性的测量发现,TiO2纳米粒子的添加使得变压器油中的浅陷阱密度达到了纯油2倍以上。通过Zeta电位的测量证实了纳米粒子与变压器油两相界面结构的存在和其性质的变化对变压器油中陷阱特性和电荷输运特性的影响。
在此基础上,提出了纳米改性变压器油的电荷传导浅陷阱理论：纳米粒子具有很大的比表面积,通过固体纳米粒子和液体介质分子间的相互作用,可以形成不同于本体材料的两相界面,导致了变压器油内部浅陷阱密度显著增大。在高场强区电离产生的电荷通过在浅陷阱间被反复捕获和释放的过程迅速迁移,提高了局部电导率,减少了流注前端的净电荷密度,避免了电荷在变压器油中的积累与电场畸变,从而抑制了变压器油中流注的发展速度。除此之外,电子通过在浅陷阱间反复捕获和释放的过程降低了其自身的碰撞能量,削弱了其对变压器油分子的电离,最终提高了变压器油的绝缘特性。
Transmission and distribution transformers form a critical, highly loaded and expensive part of the electricity generation and distribution network. Electric transformers rely on the high dielectric strength properties of insulating oil to achieve normal operation. Developing new transformer oil with excellent insulation properties means a lot to improve the safe operation level of transformer, and it is also very helpful to decrease the size and weight of ultra-high voltage transformer. Recently, many researches have been focused on the nano-modified transformer oil.
In the investigation of nano-modified transformer oil, there are some problems to be solved, among which are the long time stability of nanofluids and the effect of nanoparticle on the charge transport in nano-modified transformer oil.
In this dissertation, we aim to develop a new type of nanoparticle modified transformer oil-based nanofluids by suspending semiconductive nanoparticles TiO2into transformer oil, investigate their stability and insulating properties. It reveals that the nanofluid presented high colloidal stability, exhibiting no sedimentation after18months at room temperature (average particle size20nm). Semiconductive nanoparticles can increase the ac and lightning impulse breakdown voltages of nanofluids up to more than1.2times compared with pure oils. Especially, the velocity of streamer in nanofluids is slowed down by65%of that in pure oil. Meanwhile, the partial discharge initiate voltage (PDIV) and resistance against PD of the modified oil was also dramatically improved.
In order to promote the practical application of nanofluids, the effect of nanoparticles on the insulation properties of transformer oil in the different humidity and aged conditions was investigated. It is shown that breakdown voltages of samples decrease significantly with deterioration increase. It is interesting to notice that the discrepancy of breakdown voltage between nanofluids and pure oil become more and more obvious with deterioration increase, indicating less reduction of electrical strength in nanofluids.
To understand breakdown phenomenon in the insulating materials, the distribution of space charge and the internal electric field has been considered as a key component, which can be assessed by the pulse electroacoustic technique (PEA). The effect of nanoparticles on charge accumulation, decay and transport processes in oil and nanofluid was investigated. The charges in oil are increasing with time and result in an increasing internal field, approximately174%of the applied field. However, the field in the nanofluids appears to be'evening out' and approximately the same as the applied field. It is found that the charge decay rate for nanofluids is much higher than that for pure oil after the voltage is removed. This rapid charge decay rate is mainly associated with TiO2nanoparticles in nanofluids and effectively prevents the distortion of electric field in the oil. The mode transition and the development of streamer were studied with an ICCD camera.
In order to investigate the relationship between charge transport and the trap characteristics, thermally stimulated current method (TSC) measurements were performed. It is believed that TSC measurements can be used to investigate the nature and origin of charge carrier traps in dielectrics, including the change of the number and energy of the trap sites. It is noted that shallower trap centers with higher trap density were formed in nanofluids. The trap density in nanofluid is almost2times compared with that in pure oil. According to the Electrophoresis measurements, it is verified that the internal interfaces between nanoparticles and oil induces alter local structure in the vicinity of the nanoparticles and give rise to altered trap characteristic.
Based on our measurement results, it is believed that the surface area in contact with the oil is dramatically increased and creates large interaction zones and the corresponding higher shallow trap density. The charge created at high field in the oil can be captured by the shallow traps and decay fast by the trapping and de-trapping process, which can reduce the the velocity and amplitude of electric field wave at the point of streamer. Meanwhile, facile charge movement induced by the trapping and de-trapping process can impair the ionization process caused by fast electrons and offer more uniform internal electric field and high dielectric strength of nanofluid.
引文
[1]周春梅.论我国电力系统稳定运行[J].科技资讯,2008,1：246
[2]李睿,曹顺安,钱艺华等.变压器油中腐蚀性硫的研究现状[J].变压器,2009,46(2)：19-22
[3]王梦云.1995-1999年全国变压器类设备事故统计与分析[J].电力设备,2001,2(1)：11-19
[4]王梦云.2002-2003年国家电网公司系统变压器类设备事故统计与分析(一)[J].电力设备,2004,5(10)：20-26
[5]王梦云.110kV及以上变压器事故统计与分析[J].供用电,2005,22(2)：8-12
[6]邱信华.提高变压器油绝缘强度的途径[J].润滑油,2003,18(5)：16-19
[7]颜道容.变压器油现场过滤工艺[J].电工技术,2000,11：9
[8]宋国贵,汪志军,彭世建等.交流特高压变压器油全密封处理系统研究[J].湖北电力,2009,33(6)：8-10
[9]S. Abdi, A. Boubakeur, A. Haddad, et al. Influence of thermal aging on transformer oil properties [A]. IEEE International Conference on Dielectric Liquids[C]. Norway,2008:1-4
[10]S. Abdi, A. Boubakeur, A. Haddad, et al. Influence of artificial thermal aging on transformer oil properties[J]. Electric Power Components and Systems,2011, V39(15):1701-1711
[11]R. C. Smith, C. Liang, M. Landry, J. K. Nelson, and L. S. Schadler. The Mechanisms Leading to the Useful Electrical Properties of Polymer Nanodielectrics[J]. IEEE Trans. Dielectr. Electr. Insul.2008,V15:187-196
[12]K. Nelson and J. C. Fothergill. Internal charge behaviour of nanocomposites[J]. Nanotechnology,2004, V15:586-595
[13]Toshikatsu Tanaka and Masahiro Kozako. Proposal of a Multi-core Model for Polymer Nanocomposite Dielectrics[J], IEEE Trans. Dielectr. Electr. Insul. 2005,V12(4):669-681
[14]T. Tanaka. Dielectric Nanocomposites with Insulating Properties[J]. IEEE Trans. Dielectr. Electr. Insul,2005, V12(5):914-927
[15]U. S. Choi. Enhancing thermal conductivity of fluids with nanoparticles [A]. International mechanical engineering congress and exhibition [C]. San Francisco, 1995:99-103
[16]S. J. Kim, I. C. Bang, J. Buongiomo, et al. Effects of nanoparticle deposition on surface wettability influencing boiling heat transfer in nanofluids[J]. Applied Physics Letters,2006, V89:153107.1-3
[17]F. Herchl, P. Kopcansky, M. Timko, et al. Dielectric Properties of Magnetic Liquids in High Electric Fields[J]. ACTA Physica Polonica A,2008, V113(1): 569-572
[18]C. T. Nguyen, G. Roy, C. Gauthier, et al. Heat transfer enhancement using AbOs-water nanofluid for an electronic liquid cooling system[J]. Applied Thermal Engineering,2007, V27:1501-1506
[19]X. W. Wang, X. F. Xu,U. S. Choi. Thermal conductivity of nanoparticle-fluid mixture[J]. Journal of Thermophysics and Heat Transfer,1999, V13:474-480
[20]U. S. Choi. Enhancing thermal conductivity of fluids with containing oxide'nanoparticles[J]. Journal of Heat Transfer,1999, V2:280-289
[21]Z. H. Han, F. Y. Cao, B. Yang. Synthesis and thermal characterization of phase-changeable indium polyalphaolefin nanofluids[J]. Applied Physics Letters, 2008, V92:243041-243043
[22]H. Q. Xie, L. F. Chen. Adjustable thermal conductivity in carbon nanotube nanofluids[J]. Physics Letters A,2009, V373:1861-1864
[23]R. Walvekar, I. A. Paris, M. Khalid. Thermal conductivity of carbon nanotube nanofluid-Experimental and theoretical study [J]. Heat Transfer-Asina Research, 2012, V41(2):145-163
[24]B. Yang, Z. H. Han. Temperature-dependent thermal conductivity of nanorod-based nanofluids[J]. Applied Physics Letters,2006, V89:083111.1-3
[25]H. X. Wang, H. Zhao, S. Q. Liu. Preparation and Thermal Conductivity of Nanofluids Consisting of SiOs-Organic Composite Nanorods[J]. Journal of Inorganic and Organometallic Polymers and Materials,2011, V21(4):946-949
[26]G. J. Lee, C. K. Kim, M. K. Lee, et al. Thermal conductivity enhancement of ZnO nanofluid using one-stem physical method[J]. Thermochimica Acta,2012, V75934:1-4
[27]谢华清,陈立.纳米流体对流换热系数增大机理[J].物理学报,2009,58(4)：2513-2516
[28]Y. Hwang, J. K. Lee, C. H. Lee, et al. Stability and thermal conductivity characteristics of nanofluids[J]. Thermochimica Acta,2007,V455:70-74
[29]李艳娇,赵凯,罗志峰等.纳米流体的研究进展[J].材料导报,2008,22(11)：87-92
[30]H. T. Zhu, Y. S. Lin, Y. S. Yin. A novel one-step chemical method for preparation of copper nanofluids [J]. Journal of Colloid and Interface Science, 2004, V277(1):100-103
[31]王涛,赂仲泱,郭顺松等.可控纳米流体的制备及热导率研究[J].浙江大学学 报(工学版),2007,41(3)：514-518
[32]D. S. Wen, G. P. Lin, S. Vafaei, et al. Review of nanofluids for heat transfer applications[J]. Particuology,2009, V7(2):141-150
[33]凌智勇,张体峰,丁建宁等.Cu-水纳米流体的稳定性及其粘度的实验研究[J].功能材料,2011,42：481-483
[34]卢倩,向礼琴,黄景兴等.TiO2油基纳米流体的制备和流变性能[J].材料研究学报,2008,22(5)：500-504
[35]M. Jahanshahi, S. F. Hosseinizadeh, M. Alipanah, et al. Numerical simulation of free convection based on experimental measured conductivity in a square cavity using Water/SiCh nanofluid[J]. International Communications in Heat and Mass Transfer,2010,V37(6):687-694
[36]R. J. Goldstein, W. E. Ibele, S. V. Patankar, et al. Heat transfer-A review of 2004 literature[J]. International Journal of Heat and Mass Transfer,2010, V53: 4343-4396
[37]Y. J. Hwang, J. K. Lee, C. H. Lee, et al. Production and dispersion stability of nanoparticles in nanofluids [J]. Powder Technology,2008, V186(2):145-153
[38]Y. Q. Rao. Nanofluids:stability, phase diagram, rheology and applications [J]. Particuology,2010, V8(6):549-555
[39]R. Saidur, K. Y. Leong, H. A. Mohammad. A review on applications and challenges of nanofluids[J]. Renewable and Sustainable Energy Reviews,2009, V48(8):1646-1668
[40]R. Nasrin, S. Parvin. Investigation of buoyancy-driven flow and heat transfer in a trapezoida cavity filled with water-Cu nanofluid[J]. International Communications in Heat and Mass Transfer,2012, V39(2):270-274
[41]Q. Li, Y. M. Xuan, F. Yu. Experimental investigation of submerged single jet impingement using Cu-water nanofluid[J]. Applied Thermal Engineering,2012, V36:426-433
[42]G. A. Sheikhzadeh, A. Arefmanesh, M. H. Kheirkhah, et al. Natural convection of Cu-water nanofluid in a cavity with partially active side walls[J]. European Journal of Mechanics-B/FIuids,2011, V30(2):166-176
[43]H. J. Kim, I. C. Bang, J. Onoe. Characteristic stability of bare Au-mater nanofluids fabricated by pulsed laser ablation in liquids [J]. Optics and Lasers in Engineering,2009, V47(5):532-538
[44]乔峰.Ag、石墨烯纳米流体的制备及性能研究[D].青岛科技大学,2010
[45]Y. T. Yang, F. H. Lai. Numerical investigation of cooling performance with the use of Al2O3/water nanofluids in a radial flow system [J]. International Journal of Thermal Science,2011, V50(1):61-72
[46]S. Harikrishnan, S. Kalaiselvam. Preparation and thermal characteristics of CuO-oleic acid nanofluids as a phase change material[J]. Thermochimica Acta, 2012,V533:46-55
[47]L. S. Sundar, M. T. Naik, Sharma K. V et al. Experimental investigation of forced convection heat transfer and friction factor in a tube with FgjOa magnetic nanofluid[J]. Experimental Thermal and Fluid Science,2012, V37:65-71
[48]刘玉东,周跃国,童明伟等.Ti02-水纳米流体流变特性的实验研究[J].材料导报,2009,23(3)：14-16
[49]S. W. Lee, S. D. Park, S. Kang, et al. Investigation of viscosity and thermal conductivity of SiC nanofluids for heat transfer applications [J]. International Journal of Heat and Mass Transfer,2011, V54:433-438
[50]W. Yu, H. Q. Xie, Y. Li, et al. Experimental investigation on thermal conductivity and viscosity of aluminum nitride nanofluid[J]. Particuology,2011, V9(2):187-191
[51]王辉,骆仲泱,蔡洁聪等.Si02纳米流体透射率影响因素实验研究[J].浙江大学学报(工学版),2010,44(6)：1144-1148
[52]M. Moosavi, E. K. Goharshadei, A. Youssefi. Fabrication, characterization and measurement of some physicochemical properties of ZnO nanofluids [J]. International Journal of Heat and Fluid Flow,2010, V31:599-605
[53]V. Segal, A. Hjortsberg, A. Rabinovich, D. Nattrass, and K. Raj. AC(60Hz) and impulse breakdown strength of a colloidal fluid based on transformer oil and magnetite nanoparticles[A]. IEEE International Symposium on Electrical Insulation[C]. ISEI98,1998:619-622
[54]周泽存,沈其工,方瑜等.高电压技术[M].中国电力出版社,2007：103-115
[55]P. Kopcansky, L. Tomco, K. Marton, M. Koneracka, I. Potocova, M. Timko. The experimental study of the DC dielectric breakdown strength in magnetic fluids [J]. Journal of Magnetism and Magnetic Materials,2004, V272-276:2377-2378
[56]P. Kopcansky, L. Tomco, K. Marton, M. Koneracka, M. Timko, I. Potocova. The DC dielectric breakdown strength of magnetic fluids based on transformer oil [J]. Journal of Magnetism and Magnetic Materials,2005, V289:415-418
[57]P. P. C. Sartoratto, A. V. S. Neto, E. C. D. Lima. Preparation and electrical properties of oil-based magnetic fluids [J]. Journal of Applied Physics,2005, V97:10Q917
[58]Zhaotao Zhang, Jian Li, Pin Zou. Electrical properties of nano-modified insulating vegetable oil [A]. Annual Report Confence on Electrical Insulation Dielectric Phenomena[C], USA,2010:10.1109/CEIDP.2010.5724057
[59]Ping Zou, Jian Li, Zhaotao Zhang, and Ruijin Liao. Dielectric properties and electrodynamic process of natural ester-based insulating nanofluid[J]. Modern Physics Letters,2011, V25:2021-2031
[60]W.H.Lee, W.S.Lee, and J.C.Lee. Influence of magnetic nano particles on the breakdown voltage of transformer oil[A]. XVII International Symposium on High Voltage Engineering[C]. Germany,2011:22-26
[61]M. Chiesa, S. K. Das. Experimental investigation of the dielectric and cooling performance of colloidal suspensions in insulating media[J]. Colloids and Surfaces A:Physicochem. Eng. Aspects,2009, V335:88-97
[62]John A. Mergos, Maria D. Athanassopoulou, Theodore G. Argyropoulos, Constantine T. Dervos. Dielectric Properties of Nanopowder Dispersions in Paraffin Oil [J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2012,V19:1502-1507
[63]W.R.Viali, G.B.Alcantara, P. P. C. Sartoratto. Investigation of the molecular surface coating on the stability of insulating magnetic oil [J]. J. Phys. Chem. C 2010, V114:179-188
[64]李成榕,杜岳凡,吕玉珍.纳米粒子的添加对变压器油击穿性能的影响[A].香山科学会议第354次学术讨论会(纳米电介质的多层次结构及其宏观性能)文集[C],北京,2009：119-124
[65]周远翔.纳米改性变压器油的破坏特性[A].《2009中国电工技术学会年度专题论坛》学术会议论文集[C],泰州,2009
[66]沈谅平.纳米改性变压器油的制备及其特性研究[D].华中科技大学,2012
[67]Rongsheng Liu, Leif A.A. Pettersson, Tommaso Auletta, Olof Hjortstam. Fundamental Research on the Application of Nano Dielectrics to Transformers [A]. Electrical Insulation and Dielectric Phenomena (CEIDP)[C], USA,2011:423-427
[68]George J, Wang H, Francis O S, et al. Pettersson and Rongsheng Liu. Modeling of Streamer Propagation in Transformer Oil-Based Nano fluids [A]. Annual Report Conference on Electrical Insulation Dielectric Phenomena[C]. IEEE, 2008:361-366
[69]George J, Markus Z,Francis M, et al. Effects of nanoparticle charging on streamer development in transformer oil-based nanofluids[J]. Journal of Applied Physics,2010, V107:014310
[70]M. Meunier and N. Quirke. Molecular Modeling of Electron Trappin in Polymer Insulators [J]. J. Chem. Phys.,2000, V113:369-367
[71]M. Meunier, A. Aslanides and N. Quirke. Molecular Modeling of Electron Traps in Polymer Insulators:Chemical Defects and Impurities [J]. J. Chem. Phys., 2001,V115:2867-2881
[72]Tatsuo Takada, Yuji Hayase, Yasuhiro Tanaka. Space Charge Trapping in Electrical Potential Well Caused by Permanent and Induced Dipoles for LDPE/MgO Nanocomposite[J]. IEEE Transactions on Dielectrics and Electrical Insulation,2008, V15(1):152-160
[73]A.S. Ahuja. Augmentation of heat transport in laminar flow of polystyrene suspension.I:Experiments and result [J], J. Appl. Phys,1975,46
[74]L. Fedele, L. Colla, S. Bobbo, et al. Experimental stability analysis of different water-based nanofluids[J]. Nanoscale Research Letters,2011, V6:300.1-8
[75]M. Hasheminezhad, E. Ildstad, A. Nysveen Electrical breakdown strength of interfaces between solid insulation and transformer oil with variable water content[A].Annual Report Conference on Electrical Insulation and Dielectric Phenomena[C]. IEEE,2008:575-578
[76]Wang X, Wang Z D. Particle effect on breakdown voltage of mineral and ester based transformer oils [A].Annual Report Conference on Electrical Insulation and Dielectric Phenomena[C]. IEEE,2008:598-602
[77]C. Choi, H.S. Yoo, J.M. O. Preparation and heat transfer properties of nanoparticle-in-transformer oil dispersions as advanced energy-efficient coolants [J]. Current Applied Physics,2008, V8:710-712
[78]刘雪东,卓震.机械化学法粉体表面改性技术的发展与应用[J].江苏石油化工学院学报,2002,14(4)：32-35
[79]蒋阳,陈继贵.粉体工程[M].合肥工业大学出版社,2006：58-70
[80]王群.粉体颗粒分布常用检测方法[J].陶瓷,2011,6：38-39
[81]祁明缢.选矿粒度检测技术及其新进展[J].武汉科技大学学报(自然科学版),1987,32(3)：48-54
[82]李志慧,付乌有,许静等.单分散性Fe304纳米颗粒的制备及其表征[J].人工晶体学报,2008,37(4)：977-980
[83]李东东,李金凯,赵蔚琳.SiO2-水纳米流体稳定性及热导性能[J].济南大学学报,2010,24(3)：247-250
[84]Liu Q, Wang Z D. AC and lightning breakdown strength of mineral oil Nytro Gemini X and 10GBN [A]. International Electrical Insulation Conference[C]. INSUCON,2009:14-19
[85]Martin D, Wang Z D. Statistical analysis of the AC breakdown voltages of ester based transformer oils[J]. IEEE Transactions on Dielectrics and Electrical Insulation,2008, V15(4):1044-1050
[86]G. Chen, M. Fu, X. Z. Liu, L. S. Zhong. Ac aging and space-charge characteristics in low-density polyethylene polymeric insulation[J]. Journal of Applied Physics,2005, V110:104104
[87]J M Alison. A high field pulsed electro-acoustic apparatus for space charge and external circuit current measurement within solid insulators [J]. Meas. Sci. Technol.1998,V9:1737
[88]唐超.油纸绝缘介质的直流空间电荷特性研究[D].重庆：重庆大学,2009
[89]王云杉,周远翔,李光范.油纸绝缘介质的空间电荷积聚与消散特性[J].高电压技术,2010,34(5)：873-877
[90]Tian-chun Zhou,George Chen, Rui-jin Liao, and Zhiqiang Xu. Charge trapping and detrapping in polymeric materials:Trapping parameters [J]. Journal of Applied Physics,2011,V110:043724
[91]周凯,吴广宁,邓桃.纳米复合绝缘材料的热刺激电流测试研究[J].中国电机工程学报,2007,27(18)：76-82
[92]王力衡.介质的热刺激理论及其应用[M].科学出版社.1988：100-130
[93]Hino T. Thermally stimulated Characterstics in solid dielectrics[J]. IEEE Transactions on Electrical Insulation.1980,V15(8):301-311
[94]Sauer B B, Avakian P, Starkweather H W, Thermally stimulated current and dielectric studies of poly [J].1990,V23(24):5119-5126
[95]李成榕,丁立健,吕金壮等.氧化铝陶瓷绝缘子真空沿面闪络过程中的陷阱机制[J].中国电机工程学报,2007,27(9)：1-5
[96]R. Bartinikas, W. F. Schmidt, and E. O. Forster. Electrical Insulating Liquids [M]. ASTM Publication,1994:262-307
[97]Rongsheng Liu, Albert Jaksts. Moisture and space charge in oil-impregnated pressboard under HVDC[A]. IEEE International Conference on Conduction and Breakdown in Solid Dielectrics[C].Viistmh,1998:17-22
[98]H. Takahashi, R. Watanabe, Y. Miyauchi, and G. Mizutani, Discovery of deep and shallow trap states from step structures of rutile TiO2 vicinal surfaces by second harmonic and sum frequency generation spectroscopy [J]. J. Chem.Phys. 2011,V134:154704
[99]K.S.Suh,S.J.Hwang,J.S.Noh,T.Takada. Effects of constituents of XLPE on the formation of space charge [J]. IEEE Transactions on Dielectrics and Electrical Insulation,1994,V1(6):1077-1083
[100]梁英.高温硫化(HTV)硅橡胶电晕老化特性及机理的研究[D].华北电力大学,2008
[101]P.Morshuis, M.Jeroense. Space charge in HVDC cable insulation[A].IEEE Conference on Electrical Insulation and Dielectric Phenomena(CEIDP)[C]. Minneapolis,1997:28-31
[102]陈炯,尹毅,肖登明.电声脉冲法中脉冲对空间电荷分布测量的影响 [J].高电压技术,2006,32(5)：19-21
[103]廖瑞金,李伟,杨丽君等.变压器油纸绝缘介质在直流电场中的空间电荷输运特性[J].高电压技术,2011,37(5)：1057-1065
[104]廖瑞金,李伟,杨丽君等.不同热老化程度油纸绝缘介质在直流电场中的空间电荷特性[J].高电压技术,2011,37(9)：2197-2204
[105]Matsuoka Shingo,Sunaga Hiromi,Tanaka Ryuichi. Accμmulated Charge Profile in Polyethylene during Fast Electron Irradiations.Nuclear Science[J]. IEEE Transactions on DEI,1976,V23(5):1447-1452
[106]Tanaka Toshikatsu, Greenwood Allan. Effects of Charge Injection and Extraction on Tree Initiation in Polyethylene.Power Apparatus and Systems [J]. IEEE Transactions on DEI,1978,V97(5):1749-1759
[107]Olivier. Lesaint. "Streamers" in liquids:Relation with practical high voltage insulation and testing of liquids[A]. IEEE International Conference on Dielectric Liquids[C]. IEEE,2008:1-6
[108]Francis M O'Sullivan. A Model for the Initiation an Propagation of Electrical Streamers in Transformer Oil and Transformer Oil Based Nanofluids[D]. USA:MIT,2007
[109]Jouya Jadidian, Markus Zahn, Nils Lavesson, Ola Widlund, and Karl Borg. Impulse breakdown delay in liquid dielectrics[J]. Appl. Phys. Lett,2012, V100:192910
[110]R. Bartinikas, W. F. Schmidt, E. O. Forster, et al. Electrical Insulating Liquids, Philadelphia[M]. ASTM Publication,1994:262-307
[111]N. F. Mott, E. A. Davis. Electronic Processes in Non-Crystalline Materials[M]. Oxford,1979:152-200
[112]T.J.Lewis. Interfaces are the dominant feature of dielectrics at the nanometric level [J]. IEEE Trans. Dielectr. Electr. Insul,2004.V11:739-753
[113]D. L. Chapman. LI. A contribution to the theory of electrocapillarity [J]. Phil. Mag.1913,V25:475
[114]C. T. O'Konski. Electric properties of macromolecules. V. Theory of ionic polarization in polyelectrolytes [J]. Phys. Chem.1960, V64:605
[115]T. M. Truskett. The subtleties of water in small spaces [J]. PNAS,2003,100(18): 10139-10140
[116]E. M. Hizal, S. Diner. Breakdown time to lags and prebreakdown phenomena in transformer oil:effects of hydrostatic pressure [J]. J. Electrostatics,1982, V12: 333-343
[117]M. Krins, M. Reuter, H. Borsi, et al. Breakdown and flashover phenomena related to the presence of high absolute water contents in clean and carbonized transformer oil [A]. Annual Report Conference on Electrical Insulation and Dielectric Phenomena[C]. IEEE,2002:252-255
[118]H. Yamashita, H. Amano, A. Mori. Optical observation of pre-breakdown and breakdown phenomena in transformer oil [J]. J. Phys. D.,1977, V10: 1753-1760
[119]W. G. Chadband, J. H. Caldcrwood. The propagation of discharges in dielectric liquids[J]. J. Electrostatics,1979, V7:75-91
[120]P. P. Wong, E. O. Forster. The dynamics of electrical breakdown in liquid hydrocarbons [J]. IEEE Transactions on Electrical Insulation,1982, V17(3): 203-220
[121]H. Yamashita, H. Amano. Prebreakdown density change, current and light emission in transformer oil under non-uniform field [J]. J. Electrostatics,1982, V12:253-263
[122]K. C. Kao. New theory of electrical discharge and breakdown in low-mobility condensed insulators [J]. J. Appl. Phys.,1984, V55:752-755
[123]A. Navrotsky. Energetics of nanoparticle oxides:interplay between surface energy and polymorphism [J]. Geochemical Transactions,2003, V4(6):34-37
[124]Q. L. Zhang, L. C. Du, Y. X. Weng, L. Wang, H. Y. Chen, and J. Q. Li. Particle-size-dependent distribution of carboxylate adsorption sites on TiO2 nanoparticle surfaces:Insights into the surface modification of nanostructured TiO2 electrods [J]. J. Phys. Chem. B,2004, V108:15077-15083
[125]A.Minoda, M.Nagao, M.Kosaki. DC Short circuit Treeing Phenomenon and Space Charge Effect in EPR at Cryogenic Temperature [A].Proceedings of the sth international conference on Properties and applications of dielectric materials[C].IEEE,1997:426-429
[2]李睿,曹顺安,钱艺华等.变压器油中腐蚀性硫的研究现状[J].变压器,2009,46(2)：19-22
[3]王梦云.1995-1999年全国变压器类设备事故统计与分析[J].电力设备,2001,2(1)：11-19
[4]王梦云.2002-2003年国家电网公司系统变压器类设备事故统计与分析(一)[J].电力设备,2004,5(10)：20-26
[5]王梦云.110kV及以上变压器事故统计与分析[J].供用电,2005,22(2)：8-12
[6]邱信华.提高变压器油绝缘强度的途径[J].润滑油,2003,18(5)：16-19
[7]颜道容.变压器油现场过滤工艺[J].电工技术,2000,11：9
[8]宋国贵,汪志军,彭世建等.交流特高压变压器油全密封处理系统研究[J].湖北电力,2009,33(6)：8-10
[9]S. Abdi, A. Boubakeur, A. Haddad, et al. Influence of thermal aging on transformer oil properties [A]. IEEE International Conference on Dielectric Liquids[C]. Norway,2008:1-4
[10]S. Abdi, A. Boubakeur, A. Haddad, et al. Influence of artificial thermal aging on transformer oil properties[J]. Electric Power Components and Systems,2011, V39(15):1701-1711
[11]R. C. Smith, C. Liang, M. Landry, J. K. Nelson, and L. S. Schadler. The Mechanisms Leading to the Useful Electrical Properties of Polymer Nanodielectrics[J]. IEEE Trans. Dielectr. Electr. Insul.2008,V15:187-196
[12]K. Nelson and J. C. Fothergill. Internal charge behaviour of nanocomposites[J]. Nanotechnology,2004, V15:586-595
[13]Toshikatsu Tanaka and Masahiro Kozako. Proposal of a Multi-core Model for Polymer Nanocomposite Dielectrics[J], IEEE Trans. Dielectr. Electr. Insul. 2005,V12(4):669-681
[14]T. Tanaka. Dielectric Nanocomposites with Insulating Properties[J]. IEEE Trans. Dielectr. Electr. Insul,2005, V12(5):914-927
[15]U. S. Choi. Enhancing thermal conductivity of fluids with nanoparticles [A]. International mechanical engineering congress and exhibition [C]. San Francisco, 1995:99-103
[16]S. J. Kim, I. C. Bang, J. Buongiomo, et al. Effects of nanoparticle deposition on surface wettability influencing boiling heat transfer in nanofluids[J]. Applied Physics Letters,2006, V89:153107.1-3
[17]F. Herchl, P. Kopcansky, M. Timko, et al. Dielectric Properties of Magnetic Liquids in High Electric Fields[J]. ACTA Physica Polonica A,2008, V113(1): 569-572
[18]C. T. Nguyen, G. Roy, C. Gauthier, et al. Heat transfer enhancement using AbOs-water nanofluid for an electronic liquid cooling system[J]. Applied Thermal Engineering,2007, V27:1501-1506
[19]X. W. Wang, X. F. Xu,U. S. Choi. Thermal conductivity of nanoparticle-fluid mixture[J]. Journal of Thermophysics and Heat Transfer,1999, V13:474-480
[20]U. S. Choi. Enhancing thermal conductivity of fluids with containing oxide'nanoparticles[J]. Journal of Heat Transfer,1999, V2:280-289
[21]Z. H. Han, F. Y. Cao, B. Yang. Synthesis and thermal characterization of phase-changeable indium polyalphaolefin nanofluids[J]. Applied Physics Letters, 2008, V92:243041-243043
[22]H. Q. Xie, L. F. Chen. Adjustable thermal conductivity in carbon nanotube nanofluids[J]. Physics Letters A,2009, V373:1861-1864
[23]R. Walvekar, I. A. Paris, M. Khalid. Thermal conductivity of carbon nanotube nanofluid-Experimental and theoretical study [J]. Heat Transfer-Asina Research, 2012, V41(2):145-163
[24]B. Yang, Z. H. Han. Temperature-dependent thermal conductivity of nanorod-based nanofluids[J]. Applied Physics Letters,2006, V89:083111.1-3
[25]H. X. Wang, H. Zhao, S. Q. Liu. Preparation and Thermal Conductivity of Nanofluids Consisting of SiOs-Organic Composite Nanorods[J]. Journal of Inorganic and Organometallic Polymers and Materials,2011, V21(4):946-949
[26]G. J. Lee, C. K. Kim, M. K. Lee, et al. Thermal conductivity enhancement of ZnO nanofluid using one-stem physical method[J]. Thermochimica Acta,2012, V75934:1-4
[27]谢华清,陈立.纳米流体对流换热系数增大机理[J].物理学报,2009,58(4)：2513-2516
[28]Y. Hwang, J. K. Lee, C. H. Lee, et al. Stability and thermal conductivity characteristics of nanofluids[J]. Thermochimica Acta,2007,V455:70-74
[29]李艳娇,赵凯,罗志峰等.纳米流体的研究进展[J].材料导报,2008,22(11)：87-92
[30]H. T. Zhu, Y. S. Lin, Y. S. Yin. A novel one-step chemical method for preparation of copper nanofluids [J]. Journal of Colloid and Interface Science, 2004, V277(1):100-103
[31]王涛,赂仲泱,郭顺松等.可控纳米流体的制备及热导率研究[J].浙江大学学 报(工学版),2007,41(3)：514-518
[32]D. S. Wen, G. P. Lin, S. Vafaei, et al. Review of nanofluids for heat transfer applications[J]. Particuology,2009, V7(2):141-150
[33]凌智勇,张体峰,丁建宁等.Cu-水纳米流体的稳定性及其粘度的实验研究[J].功能材料,2011,42：481-483
[34]卢倩,向礼琴,黄景兴等.TiO2油基纳米流体的制备和流变性能[J].材料研究学报,2008,22(5)：500-504
[35]M. Jahanshahi, S. F. Hosseinizadeh, M. Alipanah, et al. Numerical simulation of free convection based on experimental measured conductivity in a square cavity using Water/SiCh nanofluid[J]. International Communications in Heat and Mass Transfer,2010,V37(6):687-694
[36]R. J. Goldstein, W. E. Ibele, S. V. Patankar, et al. Heat transfer-A review of 2004 literature[J]. International Journal of Heat and Mass Transfer,2010, V53: 4343-4396
[37]Y. J. Hwang, J. K. Lee, C. H. Lee, et al. Production and dispersion stability of nanoparticles in nanofluids [J]. Powder Technology,2008, V186(2):145-153
[38]Y. Q. Rao. Nanofluids:stability, phase diagram, rheology and applications [J]. Particuology,2010, V8(6):549-555
[39]R. Saidur, K. Y. Leong, H. A. Mohammad. A review on applications and challenges of nanofluids[J]. Renewable and Sustainable Energy Reviews,2009, V48(8):1646-1668
[40]R. Nasrin, S. Parvin. Investigation of buoyancy-driven flow and heat transfer in a trapezoida cavity filled with water-Cu nanofluid[J]. International Communications in Heat and Mass Transfer,2012, V39(2):270-274
[41]Q. Li, Y. M. Xuan, F. Yu. Experimental investigation of submerged single jet impingement using Cu-water nanofluid[J]. Applied Thermal Engineering,2012, V36:426-433
[42]G. A. Sheikhzadeh, A. Arefmanesh, M. H. Kheirkhah, et al. Natural convection of Cu-water nanofluid in a cavity with partially active side walls[J]. European Journal of Mechanics-B/FIuids,2011, V30(2):166-176
[43]H. J. Kim, I. C. Bang, J. Onoe. Characteristic stability of bare Au-mater nanofluids fabricated by pulsed laser ablation in liquids [J]. Optics and Lasers in Engineering,2009, V47(5):532-538
[44]乔峰.Ag、石墨烯纳米流体的制备及性能研究[D].青岛科技大学,2010
[45]Y. T. Yang, F. H. Lai. Numerical investigation of cooling performance with the use of Al2O3/water nanofluids in a radial flow system [J]. International Journal of Thermal Science,2011, V50(1):61-72
[46]S. Harikrishnan, S. Kalaiselvam. Preparation and thermal characteristics of CuO-oleic acid nanofluids as a phase change material[J]. Thermochimica Acta, 2012,V533:46-55
[47]L. S. Sundar, M. T. Naik, Sharma K. V et al. Experimental investigation of forced convection heat transfer and friction factor in a tube with FgjOa magnetic nanofluid[J]. Experimental Thermal and Fluid Science,2012, V37:65-71
[48]刘玉东,周跃国,童明伟等.Ti02-水纳米流体流变特性的实验研究[J].材料导报,2009,23(3)：14-16
[49]S. W. Lee, S. D. Park, S. Kang, et al. Investigation of viscosity and thermal conductivity of SiC nanofluids for heat transfer applications [J]. International Journal of Heat and Mass Transfer,2011, V54:433-438
[50]W. Yu, H. Q. Xie, Y. Li, et al. Experimental investigation on thermal conductivity and viscosity of aluminum nitride nanofluid[J]. Particuology,2011, V9(2):187-191
[51]王辉,骆仲泱,蔡洁聪等.Si02纳米流体透射率影响因素实验研究[J].浙江大学学报(工学版),2010,44(6)：1144-1148
[52]M. Moosavi, E. K. Goharshadei, A. Youssefi. Fabrication, characterization and measurement of some physicochemical properties of ZnO nanofluids [J]. International Journal of Heat and Fluid Flow,2010, V31:599-605
[53]V. Segal, A. Hjortsberg, A. Rabinovich, D. Nattrass, and K. Raj. AC(60Hz) and impulse breakdown strength of a colloidal fluid based on transformer oil and magnetite nanoparticles[A]. IEEE International Symposium on Electrical Insulation[C]. ISEI98,1998:619-622
[54]周泽存,沈其工,方瑜等.高电压技术[M].中国电力出版社,2007：103-115
[55]P. Kopcansky, L. Tomco, K. Marton, M. Koneracka, I. Potocova, M. Timko. The experimental study of the DC dielectric breakdown strength in magnetic fluids [J]. Journal of Magnetism and Magnetic Materials,2004, V272-276:2377-2378
[56]P. Kopcansky, L. Tomco, K. Marton, M. Koneracka, M. Timko, I. Potocova. The DC dielectric breakdown strength of magnetic fluids based on transformer oil [J]. Journal of Magnetism and Magnetic Materials,2005, V289:415-418
[57]P. P. C. Sartoratto, A. V. S. Neto, E. C. D. Lima. Preparation and electrical properties of oil-based magnetic fluids [J]. Journal of Applied Physics,2005, V97:10Q917
[58]Zhaotao Zhang, Jian Li, Pin Zou. Electrical properties of nano-modified insulating vegetable oil [A]. Annual Report Confence on Electrical Insulation Dielectric Phenomena[C], USA,2010:10.1109/CEIDP.2010.5724057
[59]Ping Zou, Jian Li, Zhaotao Zhang, and Ruijin Liao. Dielectric properties and electrodynamic process of natural ester-based insulating nanofluid[J]. Modern Physics Letters,2011, V25:2021-2031
[60]W.H.Lee, W.S.Lee, and J.C.Lee. Influence of magnetic nano particles on the breakdown voltage of transformer oil[A]. XVII International Symposium on High Voltage Engineering[C]. Germany,2011:22-26
[61]M. Chiesa, S. K. Das. Experimental investigation of the dielectric and cooling performance of colloidal suspensions in insulating media[J]. Colloids and Surfaces A:Physicochem. Eng. Aspects,2009, V335:88-97
[62]John A. Mergos, Maria D. Athanassopoulou, Theodore G. Argyropoulos, Constantine T. Dervos. Dielectric Properties of Nanopowder Dispersions in Paraffin Oil [J]. IEEE Transactions on Dielectrics and Electrical Insulation, 2012,V19:1502-1507
[63]W.R.Viali, G.B.Alcantara, P. P. C. Sartoratto. Investigation of the molecular surface coating on the stability of insulating magnetic oil [J]. J. Phys. Chem. C 2010, V114:179-188
[64]李成榕,杜岳凡,吕玉珍.纳米粒子的添加对变压器油击穿性能的影响[A].香山科学会议第354次学术讨论会(纳米电介质的多层次结构及其宏观性能)文集[C],北京,2009：119-124
[65]周远翔.纳米改性变压器油的破坏特性[A].《2009中国电工技术学会年度专题论坛》学术会议论文集[C],泰州,2009
[66]沈谅平.纳米改性变压器油的制备及其特性研究[D].华中科技大学,2012
[67]Rongsheng Liu, Leif A.A. Pettersson, Tommaso Auletta, Olof Hjortstam. Fundamental Research on the Application of Nano Dielectrics to Transformers [A]. Electrical Insulation and Dielectric Phenomena (CEIDP)[C], USA,2011:423-427
[68]George J, Wang H, Francis O S, et al. Pettersson and Rongsheng Liu. Modeling of Streamer Propagation in Transformer Oil-Based Nano fluids [A]. Annual Report Conference on Electrical Insulation Dielectric Phenomena[C]. IEEE, 2008:361-366
[69]George J, Markus Z,Francis M, et al. Effects of nanoparticle charging on streamer development in transformer oil-based nanofluids[J]. Journal of Applied Physics,2010, V107:014310
[70]M. Meunier and N. Quirke. Molecular Modeling of Electron Trappin in Polymer Insulators [J]. J. Chem. Phys.,2000, V113:369-367
[71]M. Meunier, A. Aslanides and N. Quirke. Molecular Modeling of Electron Traps in Polymer Insulators:Chemical Defects and Impurities [J]. J. Chem. Phys., 2001,V115:2867-2881
[72]Tatsuo Takada, Yuji Hayase, Yasuhiro Tanaka. Space Charge Trapping in Electrical Potential Well Caused by Permanent and Induced Dipoles for LDPE/MgO Nanocomposite[J]. IEEE Transactions on Dielectrics and Electrical Insulation,2008, V15(1):152-160
[73]A.S. Ahuja. Augmentation of heat transport in laminar flow of polystyrene suspension.I:Experiments and result [J], J. Appl. Phys,1975,46
[74]L. Fedele, L. Colla, S. Bobbo, et al. Experimental stability analysis of different water-based nanofluids[J]. Nanoscale Research Letters,2011, V6:300.1-8
[75]M. Hasheminezhad, E. Ildstad, A. Nysveen Electrical breakdown strength of interfaces between solid insulation and transformer oil with variable water content[A].Annual Report Conference on Electrical Insulation and Dielectric Phenomena[C]. IEEE,2008:575-578
[76]Wang X, Wang Z D. Particle effect on breakdown voltage of mineral and ester based transformer oils [A].Annual Report Conference on Electrical Insulation and Dielectric Phenomena[C]. IEEE,2008:598-602
[77]C. Choi, H.S. Yoo, J.M. O. Preparation and heat transfer properties of nanoparticle-in-transformer oil dispersions as advanced energy-efficient coolants [J]. Current Applied Physics,2008, V8:710-712
[78]刘雪东,卓震.机械化学法粉体表面改性技术的发展与应用[J].江苏石油化工学院学报,2002,14(4)：32-35
[79]蒋阳,陈继贵.粉体工程[M].合肥工业大学出版社,2006：58-70
[80]王群.粉体颗粒分布常用检测方法[J].陶瓷,2011,6：38-39
[81]祁明缢.选矿粒度检测技术及其新进展[J].武汉科技大学学报(自然科学版),1987,32(3)：48-54
[82]李志慧,付乌有,许静等.单分散性Fe304纳米颗粒的制备及其表征[J].人工晶体学报,2008,37(4)：977-980
[83]李东东,李金凯,赵蔚琳.SiO2-水纳米流体稳定性及热导性能[J].济南大学学报,2010,24(3)：247-250
[84]Liu Q, Wang Z D. AC and lightning breakdown strength of mineral oil Nytro Gemini X and 10GBN [A]. International Electrical Insulation Conference[C]. INSUCON,2009:14-19
[85]Martin D, Wang Z D. Statistical analysis of the AC breakdown voltages of ester based transformer oils[J]. IEEE Transactions on Dielectrics and Electrical Insulation,2008, V15(4):1044-1050
[86]G. Chen, M. Fu, X. Z. Liu, L. S. Zhong. Ac aging and space-charge characteristics in low-density polyethylene polymeric insulation[J]. Journal of Applied Physics,2005, V110:104104
[87]J M Alison. A high field pulsed electro-acoustic apparatus for space charge and external circuit current measurement within solid insulators [J]. Meas. Sci. Technol.1998,V9:1737
[88]唐超.油纸绝缘介质的直流空间电荷特性研究[D].重庆：重庆大学,2009
[89]王云杉,周远翔,李光范.油纸绝缘介质的空间电荷积聚与消散特性[J].高电压技术,2010,34(5)：873-877
[90]Tian-chun Zhou,George Chen, Rui-jin Liao, and Zhiqiang Xu. Charge trapping and detrapping in polymeric materials:Trapping parameters [J]. Journal of Applied Physics,2011,V110:043724
[91]周凯,吴广宁,邓桃.纳米复合绝缘材料的热刺激电流测试研究[J].中国电机工程学报,2007,27(18)：76-82
[92]王力衡.介质的热刺激理论及其应用[M].科学出版社.1988：100-130
[93]Hino T. Thermally stimulated Characterstics in solid dielectrics[J]. IEEE Transactions on Electrical Insulation.1980,V15(8):301-311
[94]Sauer B B, Avakian P, Starkweather H W, Thermally stimulated current and dielectric studies of poly [J].1990,V23(24):5119-5126
[95]李成榕,丁立健,吕金壮等.氧化铝陶瓷绝缘子真空沿面闪络过程中的陷阱机制[J].中国电机工程学报,2007,27(9)：1-5
[96]R. Bartinikas, W. F. Schmidt, and E. O. Forster. Electrical Insulating Liquids [M]. ASTM Publication,1994:262-307
[97]Rongsheng Liu, Albert Jaksts. Moisture and space charge in oil-impregnated pressboard under HVDC[A]. IEEE International Conference on Conduction and Breakdown in Solid Dielectrics[C].Viistmh,1998:17-22
[98]H. Takahashi, R. Watanabe, Y. Miyauchi, and G. Mizutani, Discovery of deep and shallow trap states from step structures of rutile TiO2 vicinal surfaces by second harmonic and sum frequency generation spectroscopy [J]. J. Chem.Phys. 2011,V134:154704
[99]K.S.Suh,S.J.Hwang,J.S.Noh,T.Takada. Effects of constituents of XLPE on the formation of space charge [J]. IEEE Transactions on Dielectrics and Electrical Insulation,1994,V1(6):1077-1083
[100]梁英.高温硫化(HTV)硅橡胶电晕老化特性及机理的研究[D].华北电力大学,2008
[101]P.Morshuis, M.Jeroense. Space charge in HVDC cable insulation[A].IEEE Conference on Electrical Insulation and Dielectric Phenomena(CEIDP)[C]. Minneapolis,1997:28-31
[102]陈炯,尹毅,肖登明.电声脉冲法中脉冲对空间电荷分布测量的影响 [J].高电压技术,2006,32(5)：19-21
[103]廖瑞金,李伟,杨丽君等.变压器油纸绝缘介质在直流电场中的空间电荷输运特性[J].高电压技术,2011,37(5)：1057-1065
[104]廖瑞金,李伟,杨丽君等.不同热老化程度油纸绝缘介质在直流电场中的空间电荷特性[J].高电压技术,2011,37(9)：2197-2204
[105]Matsuoka Shingo,Sunaga Hiromi,Tanaka Ryuichi. Accμmulated Charge Profile in Polyethylene during Fast Electron Irradiations.Nuclear Science[J]. IEEE Transactions on DEI,1976,V23(5):1447-1452
[106]Tanaka Toshikatsu, Greenwood Allan. Effects of Charge Injection and Extraction on Tree Initiation in Polyethylene.Power Apparatus and Systems [J]. IEEE Transactions on DEI,1978,V97(5):1749-1759
[107]Olivier. Lesaint. "Streamers" in liquids:Relation with practical high voltage insulation and testing of liquids[A]. IEEE International Conference on Dielectric Liquids[C]. IEEE,2008:1-6
[108]Francis M O'Sullivan. A Model for the Initiation an Propagation of Electrical Streamers in Transformer Oil and Transformer Oil Based Nanofluids[D]. USA:MIT,2007
[109]Jouya Jadidian, Markus Zahn, Nils Lavesson, Ola Widlund, and Karl Borg. Impulse breakdown delay in liquid dielectrics[J]. Appl. Phys. Lett,2012, V100:192910
[110]R. Bartinikas, W. F. Schmidt, E. O. Forster, et al. Electrical Insulating Liquids, Philadelphia[M]. ASTM Publication,1994:262-307
[111]N. F. Mott, E. A. Davis. Electronic Processes in Non-Crystalline Materials[M]. Oxford,1979:152-200
[112]T.J.Lewis. Interfaces are the dominant feature of dielectrics at the nanometric level [J]. IEEE Trans. Dielectr. Electr. Insul,2004.V11:739-753
[113]D. L. Chapman. LI. A contribution to the theory of electrocapillarity [J]. Phil. Mag.1913,V25:475
[114]C. T. O'Konski. Electric properties of macromolecules. V. Theory of ionic polarization in polyelectrolytes [J]. Phys. Chem.1960, V64:605
[115]T. M. Truskett. The subtleties of water in small spaces [J]. PNAS,2003,100(18): 10139-10140
[116]E. M. Hizal, S. Diner. Breakdown time to lags and prebreakdown phenomena in transformer oil:effects of hydrostatic pressure [J]. J. Electrostatics,1982, V12: 333-343
[117]M. Krins, M. Reuter, H. Borsi, et al. Breakdown and flashover phenomena related to the presence of high absolute water contents in clean and carbonized transformer oil [A]. Annual Report Conference on Electrical Insulation and Dielectric Phenomena[C]. IEEE,2002:252-255
[118]H. Yamashita, H. Amano, A. Mori. Optical observation of pre-breakdown and breakdown phenomena in transformer oil [J]. J. Phys. D.,1977, V10: 1753-1760
[119]W. G. Chadband, J. H. Caldcrwood. The propagation of discharges in dielectric liquids[J]. J. Electrostatics,1979, V7:75-91
[120]P. P. Wong, E. O. Forster. The dynamics of electrical breakdown in liquid hydrocarbons [J]. IEEE Transactions on Electrical Insulation,1982, V17(3): 203-220
[121]H. Yamashita, H. Amano. Prebreakdown density change, current and light emission in transformer oil under non-uniform field [J]. J. Electrostatics,1982, V12:253-263
[122]K. C. Kao. New theory of electrical discharge and breakdown in low-mobility condensed insulators [J]. J. Appl. Phys.,1984, V55:752-755
[123]A. Navrotsky. Energetics of nanoparticle oxides:interplay between surface energy and polymorphism [J]. Geochemical Transactions,2003, V4(6):34-37
[124]Q. L. Zhang, L. C. Du, Y. X. Weng, L. Wang, H. Y. Chen, and J. Q. Li. Particle-size-dependent distribution of carboxylate adsorption sites on TiO2 nanoparticle surfaces:Insights into the surface modification of nanostructured TiO2 electrods [J]. J. Phys. Chem. B,2004, V108:15077-15083
[125]A.Minoda, M.Nagao, M.Kosaki. DC Short circuit Treeing Phenomenon and Space Charge Effect in EPR at Cryogenic Temperature [A].Proceedings of the sth international conference on Properties and applications of dielectric materials[C].IEEE,1997:426-429