学科分类
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3 个结果
  • 简介:Radiointerference(RI),asanaftereffectofcoronadischarge,isanimportantresearchtopicinthefieldofelectromagneticcompatibility,whereexcitationfunctionisappliedbroadlytothepredictionofRIlevel.ThispaperpresentsthetheoryofexcitationfunctionmethodusedintheRIlevelprediction.Then,somepracticalproblemsrelatedtothismethodarediscussed.Thepropagationprocedureofcoronacurrentissolvedbythephase-modaltransformation,andtheimpedancematrixofmultitransmissionlinesiscalculatedbyadoublelogarithmicapproximatemodelofCarson'sGround-Returnimpedance.Atthesametime,inordertocalculatetheRIlevelwhentotallinecoronaisassumed,ananalyticalformulaisdeducedforintegraloperation.Basedontheabovesolutions,analgorithmispresentedandappliedtothepredictionofRIlevelofapracticaloverheadtransmissionline.Comparisonofpredictionandmeasurementresultsindicatesthatthealgorithmproposedinthispaperiseffectiveandfeasible.

  • 标签: 电晕放电 预测 激励 应用 架空输电线路
  • 简介:Ionopticsisacriticalcomponentofionthrusters.Atwo-dimensionalaxisymmetricmodelisdevelopedtostudythecharacteristicsofthree-gridelectroncyclotronresonanceionthrusteroptics.Thecodeisbasedonaparticle-in-cellcombinedwiththeMonteCarlocollisionmethodtosimulateiondynamicsandcharge-exchangeprocessesinthegridregion.Thesimulationresultsshowthatthemodecangiveareasonableestimateofthephysicscharacteristicsoftheionoptics.Thedesignoftheionopticssatisfiestherequirementofpreventingelectronbackstreaming.Charge-exchangeionscancausedamagetothegrids,especiallytotheacceleratorgrid.'Barrel'erosioncanincreasetheacceleratorgridapertureradiusatarateof1.91×10~(-11)m/s,whilethedeceleratorgridplaysanimportantroleinreducing'pits-and-grooves'erosion.

  • 标签: 离子推进器 侵蚀预报 离子光学 粒子模拟 ECR 电子回旋共振
  • 简介:Thispaperproposesanewmethodtopredictthecoronaonsetvoltageforarodplaneairgap,basedonthesupportvectormachine(SVM).BecausetheSVMisnotlimitedbythesize,dimensionandnonlinearityofthesamples,thismethodcanrealizeaccuratepredictionwithfewtrainingdata.Onlyelectricfieldfeaturesarechosenastheinput;nogeometricparameterisincluded.Therefore,theexperimentdataofonekindofelectrodecanbeusedtopredictthecoronaonsetvoltagesofotherelectrodeswithdifferentsizes.Withtheexperimentaldataobtainedbyozonedetectiontechnology,andexperimentaldataprovidedbythereference,theefficiencyoftheproposedmethodisvalidated.Accuratepredictedresultswithanaveragerelativelessthan3%areobtainedwithonly6experimentaldata.

  • 标签: 支持向量机 起始电压 直流电晕 预测 实验数据 气隙