EMC 测试

IntroductiontoEMCDecember2008电磁兼容(EMC)介绍IntroductionToEMC电磁兼容EMC(ElectromagneticCompatibility)的定义：装置能在身处的电磁环境中正常工作而本身产生的电磁干扰不影响环境中其他装置的正常工作。EMCstandsforElectro-MagneticCompatibility.Itistheabilityofasystemorproducttofunctionproperlyinitselectromagneticenvironment,withoutintroducingintolerableelectromagneticdisturbancestoanythinginthatenvironment.EMC包括电磁干扰（EMI）和抗电磁干扰（EMS）两个部分。ItcoversbothElectro-MagneticInterference(EMI)andElectro-MagneticSusceptibility(EMS).什么是EMCWhatisEMC?电磁兼容发射干扰抗扰传导发射辐射发射传导抗扰辐射抗扰什么是EMCWhatisEMC?EMC(ElectroMagneticCompatibility)EMS(Immunity)(ElectroMagneticSusceptibility)EMI(ElectroMagneticInterference)ConductedImmunityRadiatedImmunityConductedEmissionRadiatedEmission主题TOPICS1.发射干扰Emission2.抗扰Immunity3.10m半波暗室10mSAC4.屏蔽室LocalShieldedRoom发射干扰是指产品或系统沿着电力线传输或通过空间传输的射频电磁能量，并对其所处的电磁环境造成干扰或污染。Emissionistheradiofrequencyenergyofaproductorsystembeingtransmittedalongthepowercordorthroughspaceasunwantedelectromagneticpollution/interferences.发射干扰可以分为两部分：Emissionrequirementscanbedividedintotwocategories:传导发射-传导发射标准的限值规定了150KHz到30MHz的频率范围内通过与系统连接的电缆（电源线、信号线等）耦合的传导干扰。ConductedEmissions-Conductedemissionsstandardslimittheconducteddisturbancesinthe150KHzto30MHzfrequencyrange.Thislimitstheemissionscoupledthroughcable(mains,signalcables)connectingtothesystem.辐射发射-辐射发射的限值是在30MHz到1GHz频率范围内规定的，它保证了设备不会干扰到附近运行的系统。RadiatedEmission-Radiatedemissionsstandardsimposelimitsontheradiateddisturbancesinthe30MHzto1GHzfrequencyrange.Thisensuresthattheequipmentwillnotinterferewiththeoperationofsystemsinitsvicinity.1.发射干扰Emission1.1传导发射测试ConductedEmissionTest(Conducted)1.2辐射发射测试RadiatedEmissionTest(Radiated)1.3干扰功率测试PowerInterferenceTest(Radiated)1.4非连续干扰测试DiscontinuousDisturbancesTest(Conducted)1.5电流谐波测试HarmonicsCurrentTest(Conducted)1.6电压闪爍测试FlickerTest(Conducted)1.发射干扰Emission这项测试检测产生于EUT(待测物)内部并且通过I/O线，控制线或电源线传输的干扰。要求EUT产生的传导发射干扰小于如CISPR22orEN55022等国际标准所规定的限值。AtestistomeasurethepotentialinterferencegeneratedinsideanEUTandcarriedthroughtheI/Olines,thecontrolleads,orpowerlines.ThistestisrequiredtoensurethattheconductedemissionofthetestedEUTmeetspre-definedlimitsassetbyvariousnationalandinternationalstandardse.g.CISPR22orEN55022.EUT0.8mLISNbundledto40mm0.4m0.8mMainsexcessleadHorizontalGroundPlaneVerticalGroundPlaneSupplyMainsReceiver1.1传导发射测试ConductedEmissionTest限值线LimitLines1.1传导发射测试ConductedEmissionTest1.1传导发射测试ConductedEmissionTestPeakdetectorCreatetableoffrequenciesResultAvg.limit?ResultQPlimit?QPdetectorResultQPlimit?ResultAvg.limit?ResultAvg.limit?Avg.detectorFailPassNNNNNYYYYY以峰值检坡器测量时使用的决策树。Decisiontreeforpeakdetectormeasurement.应用EN55022标准的波形示例SampleplotforEN550221.1传导发射测试ConductedEmissionTestEquipmentListEquipmentCapabilityManufacturerEMIReceiver-SCR3052CFrequencyRange:9kHzto2.75GHzSchaffnerRFSwitch–NS4901DualChannelToyoSpectrumAnalyzer–R3131AFrequencyRange:9kHzto3GHzAdvantestLISN–NNB42CImpedance:50ohmsSchaffnerSpectrumAnalyzerEMIReceiverRFSwitchLISN(LineImpedanceStabilizingNetwork)1.1传导发射测试ConductedEmissionTest这项测试检测EUT产生的通过空间传播的干扰信号,这些信号由天线接收，由接收机测量，从而保证能符合例如CISPR22等相关EMC标准。天线放置在离EUT10米远的地方，在1米到4米间的高度上测量水平和垂直两个方向。放置在转台桌子上的EUT随着桌子做360度的旋转。AtestthatlooksfordisturbancesignalsthataretransmittedbytheEUTthroughspace.ThesesignalsarethenreceivedbytheantennaandmeasuredwithareceivertoensurethattheyarebelowtheacceptablelimitssetbytherelevantEMCstandard,e.g.CISPR22.Theantennaispositioned10mfromtheEUTandisorientedinbothhorizontalandverticalpolarizationforaheightfrom1mto4m.TheEUTwillberotatedin360degreeontheturntable.1.2辐射发射测试RadiatedEmissionTestEUT0.8mTurntablemains1mto4mGroundPlaneMeasurementDistance=10m1.2辐射发射测试RadiatedEmissionTestPeakdetectorCreatetableoffrequenciesResultQPlimit-XQPdetectorResultQPlimit?FailPassMaximizeateachfrequencyNYNY以峰值检坡器测量时使用的决策树。Decisiontreeforpeakdetectormeasurement.EquipmentListEquipmentCapabilityManufacturerEMIReceiver-SCR3512FrequencyRange:9kHzto2.75GHzSchaffnerRFSwitch–NS4901DualChannelToyoSpectrumAnalyzer–R3132AFrequencyRange:9kHzto3GHzAdvantestPre-amplifier–8447DFrequencyRange:100kHzto1.3GHzAgilentBilogAntenna–CBL6112BFrequencyRange:30MHzto2GHzSchaffnerAttenuationClamp–CMAD10-3FrequencyRange:30MHzto1GHzSchaffnerAntennaEMIReceiverSpectrumAnalyzerRFSwitchPre-amplifierAttenuationClamp1.2辐射发射测试RadiatedEmissionTest此项测试使用吸收钳来测量连接线上的干扰功率。连续干扰可能是宽带干扰，由机械开关、换向器、或半导体整流管等开关设备产生。也可能是窄带干扰，由单片机等电子控制装置等产生。Ameasurementofdisturbancespoweronconnectedcables,usinganabsorbingclamp.Continuousdisturbancemaybeeitherbroadband,causedbyswitchingdevicessuchasmechanicalswitches,commutatorsorsemiconductorregulators,ormaybenarrowband,causedbyelectroniccontroldevicessuchasmicroprocessors.1.3干扰功率测试PowerInterferenceTestCISPR14-1或EN55014-1标准所涉及的家用电器，电动工具以及类似设备需要进行此项测试。Thistestisapplicabletohouseholdappliances,electrictoolsandsimilarapparatustomeettheemissionstandardCISPR14-1orEN55014-1.EUT0.8mMeasurementDistance=5mTospectrumanalyzerortestreceiverAbsorbingClampAuxiliaryClampToMainsSupplyEquipmentListEquipmentCapabilityManufacturerEMIReceiver-HP8542EFrequencyrange:9kHzto2.9GHzHPAbsorbingClamp–AMZ41CFrequencyrange: