资源描述：
《基于线路雷电流波形特征的雷击故障定位与雷电参数反演分析》由会员上传分享，免费在线阅读，更多相关内容在行业资料-天天文库。
1、重庆大学硕士学位论文II英文摘要ABSTRACTTransmissionlinehasthelengthofthousandsofmilesandcomplicatedtopography.Accordingtothestatisticsdata,theproportionofthepoweroutagetimescausedbylightningstrokesaccountsfor40%-70%ofthetotalinChina,whichseriouslyaffectsthesafety,reliabilityandstabilityofoperatio
2、nforpowersystem.Thetraditionalwaytofindthelightningfaultspanartificiallyistime-consuming,whichwillcauseoutagesinsupplyandeconomiclosses.Atpresentthelightningprotectiondesignismainlybasedonthefixedlightningparameterswithoutconsideringtheinfluenceoflandform,towerstructureandothers,wh
3、ichcannotaccuratelyreflectitsperformance.Thusresearchonthetechniquesoflightninglocationfortransmissionline,thelightningpropagationandparametersinversion,canprovidetheoreticalbasisforthedifferentiatedlightningprotectiondesign,accidentquickfix,lightningwarningandothers.Consideringthe
4、specialmeasurementofthenon-contactlightningmonitoringsystemdesignedbyourresearchgroup,thetraditionalsingle-endanddouble-endmethodsareimprovedandanovellightninglocationmethodisputforward.Thelightningrangeandsourcesofreflectedwavescanbedeterminedaccordingtothearrivaltimeandthepolarit
5、yofthefirstwave.Byusingwavelettransformthecorrespondingarrivaltimecanbeextractedandthecorrespondingformulaischosenforcalculation.Thesimulationandfielddatashowthatthemethodwiththeerrorrateoflessthan0.5%ispreciserthanthetraditionalmethods.Theerrorrateoftheimproveddouble-endmethodissm
6、allerthanthatoftheimprovedsingle-endmethod.Theformerismoresuitablefortheapplication.Basedontheformerstudy,adistributedlightningfaultlocationmethodisproposed.Firstlyaccordingtothetransientcurrentwavepolaritydifferencesofthreephases,thetypesoflightningarerecognized,suchasshieldingfai
7、lure,lightningstroketothetowerandthegroundwire.Thenthelightningstrokerangeisdeterminedbycomparingthemodulusmaximaarrivaltimeandthepolarityofthesignals.Fortheshieldingfailure,whethertheflashoveroccursornotisjudgedbasedonthetime-windowenergyratioofthetravelingwaveandthesidesoflightni
8、ngandflashoveraredistingui
