微动磨损架空输电导线电晕特性分析-analysis of corona characteristics of fretting worn overhead transmission conductors.docx

内容摘要架空输电导线在风力作用下会产生高频振动，导致导线内线股与线股之间的接触区发生极小的相对运动，从而造成导线接触区的磨损，伴随着磨损会存在磨屑外溢现象，这些磨屑能引起周围空间场强的畸变而产生局部场强集中，降低导线的起晕电压，增加导线的放电强度。本文以35KV输电线路中常用的LGJ150/25型钢芯铝绞线为研究对象，利用自制的架空输电导线微振模拟实验装置进行了不同试验条件下微动磨损试验，制备微动磨损导线试样，并对其进行磨损量测量及电晕特性测试；建立了含微动磨损磨屑导线的二维模型，利用ANSYS有限元分析软件分析磨屑大小、尖端曲率半径及分布对导线周围空间场强分布的影响；可以得出如下结论：在试验设定的条件范围内，随着振动循环周次、激振频率、加载张力的增加，导线线股间的磨损量呈增加趋势，且靠近线夹处导线磨损量较大；酸性溶液在微振初期对导线线股间的摩擦具有润滑作用，微振后期，酸性的腐蚀作用渐渐明显使得磨损程度较干燥条件严重，随着振动循环周次、激振频率、加载张力的增加，导线电晕放电产生的光子数呈增加趋势，且靠近线夹处导线放电强度较大，酸性溶液能增加导线表面粗糙度，促进电晕放电；随着振动循环周次、激振频率、加载张力的增加，导线的起晕电压呈减小趋势，微动磨损后导线在较小的加载电压下即能产生电晕放电；仿真分析补充说明了线股间的磨屑的大小、形状和分布对导线周围空间场强分布的影响规律。上述研究结果对减少高压输电导线因电晕现象而引起的线损方面具有十分重要的理论意义和应用价值。关键词：架空输电导线磨损量电晕AbstractOverheadtransmissionlinesareoftenunderhigh-frequencyvibrationstatewhenthereiswind.Theminusculeamplituderelativemotionwouldoccurinoverheadlineamongstrandedwiresandbetweenstrandedwiresandlinehardwares.Itresultsinwearinthecontactareaofstrandedwires.Withwearthereisabrasivedustspillover.Forhigh-voltagetransmissionconductor,theweardebriscancausearoundthespacefieldintensityofdistortionandlocalfieldindensityconcentration,andreduceconductorcoronavoltage,increasethedischargecurrentstrengthoftheconductor.Inthispaper,LGJ150/25typealuminumcablesteelreinforced(ACSR)whichiswidelyusedin35KVtransmissionlinesisresearched.Wearwiresampleismadebyusingself-manufacturedoverheadlineAeolianVibrationsimulationtester,andthendothewearingcapacitymeasurementandcoronacharacteristictestonthesample.Two-dimensionalmodelofthewirewithmicro-motionabrasionweardebrisisestablished,ANSYS,whichisfiniteelementanalysissoftware,isusedanalyzingtheinfluenceofsize,tipradiusofcurvatureandthedistributionofweardebrisonthefieldintensitydistributionaroundtheconductorspace.Analysisresultsareasfollows:withtheincreaseinthevibrationcycleindex,theexcitationfrequencyandloadtension,wearingcapacityofwirestendtoincrease,andwearingcapacityofwiresclosetothewireholderislarger.Inearlyfrettingwear,acidicsolutionhaslubricationonthefrictionbetweenthewirestrands,whileinlatefrettingwear,