EMC中的两种接地技术

284河北工业科技Vol.28,No.420117HebeiJournalofIndustrialScienceandTechnologyJuly2011:10081534(2011)04027002EMC(漯河职业技术学院,河南漯河462002):电磁兼容接地设计有单点接地和多点接地2种基本方法,低频电路中要求用单点接地,高频电路中用多点接地,用多点接地设备如果不能通过EFT/B测试,可以尝试单点接地方法实验证明,对某些高频电路完全可以用单点接地方法满足EMC要求:接地技术;EMC;EFT/B:TM15:ACaseanalysisofEMCgroundingtechnologyGUOYahong(LuoheVocationalandTechnicalCollege,LuoheHenan462002,China)Abstract:TheEMCgroundingdesignconsistsofsinglepointgroundingandmultipointgrounding.Lowfrequencycircuitsrequiresinglepointgrounding,whilemultipointgroundingisusuallyusedforequipmentsofhighfrequencycircuits.However,whentheequipmentcannotpasstheEFT/Btest,singlepointgroundingcanbeusedinstead.ExperimentsprovethatsomehighfrequencycircuitscanusesinglepointgroundingtomeettheEMCrequirements.Keywords:groundingtechnology;EMC;EFT/B:20110303;:20110406::(1966),,,,1EMCEMC(),50%EMC[1],[2],,,2,1MHz,,,;10MHz,,,[35];1~10MHz,1/20,,[6]21,(20MHz),2kV1kV(EFT/B),P1,P2,P3,;P1,P2,P3,1EFT/B,2;P1,P3,P2,2EFT/B,1;P2,P3,P1,12,[7],EFT/B图1产品结构Fig.1Productstructure3EFT/B,,tr5ns,T50ns,1/(tr),60MHz[8]EUT()EFT/B[9],EFT/B,2图2试验原理图Fig.2Testschematic2,EFT,12;C1,C2EUTY;C3,C4;P1,P2,P33;PCB()PCBZ1-Zn;Zg1;Zg2P2,P3EFT/B,,[10]EFT/BEUT[10],EUTEFT/B2,,EFT/BEFT/BEUT,,,,EUT,[11],PCB,(PCB,520H;24,4~18H)3PCB,EFT/B41),2P2,P3,,P1EUT2)P1,P2,P3,,23(25[9],3),,,,EFT/B,5EMC,EFT/B,,,,2,EMC:[1].[J].,2010,27(1):4648.[2].[J].,2009(2):4344.[3].[J].,2010,33(3):912.[4].[J].,2010(6):8184.(274)2714EMC44.1ASPWeb,WebServer.aspASP,ASP,ASP.DLLASP,HTML,HTML4.2ASP+MicrosoftAccessplay.asp:OBJECTID=ActiveXname=playerCLASSID=CLSID:C3D8F2C7A5084724BC3AC247058D17EBwidth=100%height=100%VIEWASTEXTparamname=urlvalue=%=replace(http:&request.ServerVariables(SERVER_NAME)&request.QueryString(id),,%20)%paramname=uimodevalue=1paramname=playmodevalue=1paramname=autostartvalue=1/OBJECTActiveX,,,,Web,,,,5,Browser/ServerClient/Server,,:[1].[J].,2004(5):3741.[2].[J].,2005(5):6771.[3].[J].,2003(4):287289.[4].[J].,2001(4):4647.[5],.Web[J].,2002,22(1):7275.[6],.ASP[M].:,2003.(262)[4],,.:[J].,1986,11(6):463467.[5],,.:[J].,1991,16(1):2528.[6],,.[J].,2003,28(7):397398.[7],.[J].,2004,12(6):6566.(271)[5],,.[J].,2007,31(16):7982.[6],.[J].,2009(3):5759.[7],,.[J].,2010,17(5):7375.[8].[J].,2009(3):6567.[9].[M].:,2008.[10],,.[J].(),2009,27(3):229234.[11].[J].,2010,28(4):5255.27428