尖刺缺陷对SF_6气体间隙冲击放电特性的影响
|
摘要
为了了解母线尖刺缺陷对SF_6气体间隙冲击放电特性的影响,以不锈钢针模拟尖刺缺陷,研究了双指数冲击电压作用下气压、波前时间和电场不均匀度对其50%击穿电压U50以及伏秒特性的影响。首先,改变实验腔体内气压p,当波前时间很短时,间隙50%击穿电压几乎不随气压升高而变化,随着波前时间增加,U50-p曲线逐渐呈驼峰状;而不同双指数冲击电压作用下,气压对间隙伏秒特性无明显影响。改变双指数冲击电压的波前时间,间隙50%击穿电压随波前时间增加而升高,上升趋势先慢后快;外施电压波前时间较短(0.08～0.9μs)时,伏秒特性曲线斜率为负,外施电压波前时间较长(8～15μs)时,伏秒特性曲线斜率为正,并提出了一种新的方法来拟合长波前冲击电压作用下的伏秒特性曲线。最后,研究了电场不均匀度对放电特性的影响。研究发现,电场不均匀系数(f)增大,50%击穿电压几乎呈线性降低。绘制了不同f间隙的下凹盆状曲线带,发现f增大,曲线带的分散性减小,且平坦区变大。实验结果对完善现场GIS母线尖刺缺陷的检测手段有一定指导意义。
In order to research the impact breakdown characteristics of SF_6 gas gap on the condition that there exists a spike defect on the bus of GIS, a stainless steel needle is imitated as a spike defect, so as to study the influences of pressure, wavefront time and electric field non-uniformity on its 50% breakdown voltage(U50) and voltage-time(V-t)characteristics under double exponential impulse voltage. First of all, changing SF_6 pressure in experimental chamber,when the wavefront time is very short, the 50% breakdown voltage of the gap hardly changes with pressure. However,when the wavefront time increases, the U50-p curve has a hump shape. In the range of experimental settings, pressure has no significant effect on voltage-time characteristics. Secondly, influence of wavefront time of double exponential impulse voltage is studied. It is frond that the 50% breakdown voltage of the gap increases quickly with the increase of the wavefront time and with a trend of the slow rate first to the fast rate later. When the wavefront time of applied voltage is short(0.08～0.9 μs), voltage-time characteristics curve has a negative slope; when the wavefront time becomes longer(8～15 μs),the slope of voltage-time characteristics curve turns to be positive. What is more, a new method to calculate these voltage-time characteristics curves under impulse voltage with a longer wavefront time is put forward. Finally, the influence of non-uniformity on discharge characteristics is studied. It is found that the electric field non-uniform factor(f) increases,and the 50% breakdown voltage decreases almost in a linear trend. Voltage-time characteristics cluster with a concave basin shape is drawn at different f. When f increases, dispersion of voltage-time characteristics cluster is reduced and the flat region becomes larger. These experimental results have certain guiding significance to improve the field detection means of spike defects in GIS.
In order to research the impact breakdown characteristics of SF_6 gas gap on the condition that there exists a spike defect on the bus of GIS, a stainless steel needle is imitated as a spike defect, so as to study the influences of pressure, wavefront time and electric field non-uniformity on its 50% breakdown voltage(U50) and voltage-time(V-t)characteristics under double exponential impulse voltage. First of all, changing SF_6 pressure in experimental chamber,when the wavefront time is very short, the 50% breakdown voltage of the gap hardly changes with pressure. However,when the wavefront time increases, the U50-p curve has a hump shape. In the range of experimental settings, pressure has no significant effect on voltage-time characteristics. Secondly, influence of wavefront time of double exponential impulse voltage is studied. It is frond that the 50% breakdown voltage of the gap increases quickly with the increase of the wavefront time and with a trend of the slow rate first to the fast rate later. When the wavefront time of applied voltage is short(0.08～0.9 μs), voltage-time characteristics curve has a negative slope; when the wavefront time becomes longer(8～15 μs),the slope of voltage-time characteristics curve turns to be positive. What is more, a new method to calculate these voltage-time characteristics curves under impulse voltage with a longer wavefront time is put forward. Finally, the influence of non-uniformity on discharge characteristics is studied. It is found that the electric field non-uniform factor(f) increases,and the 50% breakdown voltage decreases almost in a linear trend. Voltage-time characteristics cluster with a concave basin shape is drawn at different f. When f increases, dispersion of voltage-time characteristics cluster is reduced and the flat region becomes larger. These experimental results have certain guiding significance to improve the field detection means of spike defects in GIS.
引文
[1]施围,邱毓昌,张乔根.高电压工程基础[M].北京:机械工业出版社,2006.SHI Wei, QIU Yuchang, ZHANG Qiaogen. Fundamental of high voltage engineering[M]. Beijing, China:China Machine Press, 2006.
[2]陈飞. GIS设备的发展和应用研究[D].杭州:浙江大学,2007.CHENFei.InvestigationofGISdevelopmentandapplication[D].Hangzhou, China:Zhejiang University, 2007.
[3]张璐.特快速暂态过电压下GIS典型绝缘结构放电特性研究[D].西安:西安交通大学,2014.ZHANGLu.Studyofdischargecharactersfortypicalinsulation structure of GIS under very fast transient overvoltage[D]. Xi’an, China:Xi’an Jiaotong University, 2014.
[4]严璋,朱德恒.高电压绝缘技术[M].北京:中国电力出版社,2007.YANZhang,ZHUDeheng.Highvoltageinsulationengineering[M].Beijing, China:China Electric Power Press, 2007.
[5]LIY,SHANGY,ZHANGL,etal.Analysisofveryfasttransient overvoltages(VFTO)fromonsitemeasurementson800k VGIS[J].IEEETransactionsonDielectricsandElectricalInsulation,2012,19(6):2102-2110.
[6]SRIVASTAVA K, MORCOS M. A review of some critical aspects of insulation design of GIS/GIL systems[C]∥Proceedings of 2001 IEEE PESTransmissionandDistributionConferenceandExposition.Atlanta, Georgia, USA:IEEE, 2001:787-792.
[7]康钧,徐世山,李军,等.800kVGIS设备现场冲击试验技术探讨[J].青海电力,2011,30(增刊2):1-2.KANGJun,XUShishan,LIJun,etal.Technicalresearchforfield impact test of 800kV GIS equipment[J]. Qinghai Electric Power, 2011,30(supplement 2):1-2.
[8]张璐,黄国强,张乔根,等.冲击电压下SF6间隙临界半径现象形成机理[J].高电压技术,2018,44(3):796-803.ZHANG Lu, HUANG Guoqiang, ZHANG Qiaogen, et al. Mechanism ofcriticalradiusphenomenaforSF6gapunderimpulsevoltages[J].High Voltage Engineering, 2018, 44(3):796-803.
[9]OKUBOH,BEROUALA.Recenttrendandfutureperspectivesin electrical insulation techniques in relation to sulfur hexafluoride(SF6)substitutesforhighvoltageelectricpowerequipment[J].IEEE Electrical Insulation Magazine, 2011, 27(2):34-42.
[10]WEN T, ZHANG Q G, MA J T, et al. Discharge characteristics of long SF6 gas gap with and without insulator in GIS under VFTO and LI[J].CSEE Journal of Power and Energy Systems, 2015, 3(1):16-22.
[11]张璐,张乔根,殷禹,等.特快速暂态过电压和雷电冲击下SF6长间隙伏秒特性[J].高电压技术,2013,39(6):1396-1401.ZHANGLu,ZHANGQiaogen,YINYu,etal.Voltage-time characteristics of long SF6 gap under VFTO and lightning impulse[J].High Voltage Engineering, 2013, 39(6):1396-1401.
[12]文韬,张乔根,马径坦,等.冲击电压波形参数对SF6稍不均匀电场棒-板间隙放电电压的影响[J].高电压技术,2016,42(3):936-942.WEN Tao, ZHANG Qiaogen, MA Jingtan, et al. Influence of impulse waveformparametersonbreakdownvoltageinSF6quasi-uniform electricfieldofrod-plategap[J].HighVoltageEngineering,2016,42(3):936-942.
[13]KRITHIKAG,USAS.V-tcharacteristicsusingextendeddisruptive effect model for impulses of varying front times[J]. IEEE Transactions on Dielectrics&Electrical Insulation, 2015, 22(4):2191-2195.
[14]TEKLETSADIK K, CAMPBELL L. SF6 breakdown in GIS[J]. IEEE Proceedings on Science, Measurement and Technology, 1996, 143(5):270-276.
[15]PINNEKAMP F, NIEMEYER L. Qualitative model of breakdown in SF6 in inhomogeneous gaps[J]. Journal of Physics D:Applied Physics,1983, 16:1293-1302.
[16]顾温国,邱敏昌.冲击电压下极不均匀场中SF6气体的击穿机理[J].高压电器,1997,40(1):36-40.GUWenguo,QIUYuchang.BreakdownmechanismofSF6gasin extremely inhomogeneous field under impact voltage[J]. High Voltage Apparatus, 1997,40(1):36-40.
[17]张乔根,王沛,顾温国,等.冲击电压上升率对SF6放电由流注向先导转变的影响[J].西安交通大学学报,1998,32(12):1-4.ZHANGQiaogen,WANGPei,GUWenguo,etal.Influenceof impulserisingrateonthestreamertoleadertransitioninSF6[J].Journal of Xi’an Jiaotong University, 1998, 32(12):1-4.
[18]顾温国,邱毓昌.SF6气体极不均匀场间隙伏秒特性的计算方法[J].电工技术学报,1999,14(6):39-42.GUWenguo,QIUYuchang.AmethodtocalculatetheU-tcurveof SF6 gas in nonuniform gaps[J]. Transactions of China Electrotechnical Society, 1999, 14(6):39-42.
[19]谈克雄.六氟化硫绝缘伏秒特性的理论计算[J].高电压技术,1987,13(1):3-10.TAN Kexiong. Theoretical calculation of voltage-time characteristics of SF6 insulation[J]. High Voltage Engineering, 1987, 13(1):3-10.
[20]SHARATHB,USAS.Predictionofimpulsevoltage-time characteristicsofairandoilinsulationfordifferentwavefronts[J].IEEE Transactions on Dielectrics&Electrical Insulation, 2009, 16(6):1693-1697.
[2]陈飞. GIS设备的发展和应用研究[D].杭州:浙江大学,2007.CHENFei.InvestigationofGISdevelopmentandapplication[D].Hangzhou, China:Zhejiang University, 2007.
[3]张璐.特快速暂态过电压下GIS典型绝缘结构放电特性研究[D].西安:西安交通大学,2014.ZHANGLu.Studyofdischargecharactersfortypicalinsulation structure of GIS under very fast transient overvoltage[D]. Xi’an, China:Xi’an Jiaotong University, 2014.
[4]严璋,朱德恒.高电压绝缘技术[M].北京:中国电力出版社,2007.YANZhang,ZHUDeheng.Highvoltageinsulationengineering[M].Beijing, China:China Electric Power Press, 2007.
[5]LIY,SHANGY,ZHANGL,etal.Analysisofveryfasttransient overvoltages(VFTO)fromonsitemeasurementson800k VGIS[J].IEEETransactionsonDielectricsandElectricalInsulation,2012,19(6):2102-2110.
[6]SRIVASTAVA K, MORCOS M. A review of some critical aspects of insulation design of GIS/GIL systems[C]∥Proceedings of 2001 IEEE PESTransmissionandDistributionConferenceandExposition.Atlanta, Georgia, USA:IEEE, 2001:787-792.
[7]康钧,徐世山,李军,等.800kVGIS设备现场冲击试验技术探讨[J].青海电力,2011,30(增刊2):1-2.KANGJun,XUShishan,LIJun,etal.Technicalresearchforfield impact test of 800kV GIS equipment[J]. Qinghai Electric Power, 2011,30(supplement 2):1-2.
[8]张璐,黄国强,张乔根,等.冲击电压下SF6间隙临界半径现象形成机理[J].高电压技术,2018,44(3):796-803.ZHANG Lu, HUANG Guoqiang, ZHANG Qiaogen, et al. Mechanism ofcriticalradiusphenomenaforSF6gapunderimpulsevoltages[J].High Voltage Engineering, 2018, 44(3):796-803.
[9]OKUBOH,BEROUALA.Recenttrendandfutureperspectivesin electrical insulation techniques in relation to sulfur hexafluoride(SF6)substitutesforhighvoltageelectricpowerequipment[J].IEEE Electrical Insulation Magazine, 2011, 27(2):34-42.
[10]WEN T, ZHANG Q G, MA J T, et al. Discharge characteristics of long SF6 gas gap with and without insulator in GIS under VFTO and LI[J].CSEE Journal of Power and Energy Systems, 2015, 3(1):16-22.
[11]张璐,张乔根,殷禹,等.特快速暂态过电压和雷电冲击下SF6长间隙伏秒特性[J].高电压技术,2013,39(6):1396-1401.ZHANGLu,ZHANGQiaogen,YINYu,etal.Voltage-time characteristics of long SF6 gap under VFTO and lightning impulse[J].High Voltage Engineering, 2013, 39(6):1396-1401.
[12]文韬,张乔根,马径坦,等.冲击电压波形参数对SF6稍不均匀电场棒-板间隙放电电压的影响[J].高电压技术,2016,42(3):936-942.WEN Tao, ZHANG Qiaogen, MA Jingtan, et al. Influence of impulse waveformparametersonbreakdownvoltageinSF6quasi-uniform electricfieldofrod-plategap[J].HighVoltageEngineering,2016,42(3):936-942.
[13]KRITHIKAG,USAS.V-tcharacteristicsusingextendeddisruptive effect model for impulses of varying front times[J]. IEEE Transactions on Dielectrics&Electrical Insulation, 2015, 22(4):2191-2195.
[14]TEKLETSADIK K, CAMPBELL L. SF6 breakdown in GIS[J]. IEEE Proceedings on Science, Measurement and Technology, 1996, 143(5):270-276.
[15]PINNEKAMP F, NIEMEYER L. Qualitative model of breakdown in SF6 in inhomogeneous gaps[J]. Journal of Physics D:Applied Physics,1983, 16:1293-1302.
[16]顾温国,邱敏昌.冲击电压下极不均匀场中SF6气体的击穿机理[J].高压电器,1997,40(1):36-40.GUWenguo,QIUYuchang.BreakdownmechanismofSF6gasin extremely inhomogeneous field under impact voltage[J]. High Voltage Apparatus, 1997,40(1):36-40.
[17]张乔根,王沛,顾温国,等.冲击电压上升率对SF6放电由流注向先导转变的影响[J].西安交通大学学报,1998,32(12):1-4.ZHANGQiaogen,WANGPei,GUWenguo,etal.Influenceof impulserisingrateonthestreamertoleadertransitioninSF6[J].Journal of Xi’an Jiaotong University, 1998, 32(12):1-4.
[18]顾温国,邱毓昌.SF6气体极不均匀场间隙伏秒特性的计算方法[J].电工技术学报,1999,14(6):39-42.GUWenguo,QIUYuchang.AmethodtocalculatetheU-tcurveof SF6 gas in nonuniform gaps[J]. Transactions of China Electrotechnical Society, 1999, 14(6):39-42.
[19]谈克雄.六氟化硫绝缘伏秒特性的理论计算[J].高电压技术,1987,13(1):3-10.TAN Kexiong. Theoretical calculation of voltage-time characteristics of SF6 insulation[J]. High Voltage Engineering, 1987, 13(1):3-10.
[20]SHARATHB,USAS.Predictionofimpulsevoltage-time characteristicsofairandoilinsulationfordifferentwavefronts[J].IEEE Transactions on Dielectrics&Electrical Insulation, 2009, 16(6):1693-1697.