二表法测量三相电路有功功率

29820078武汉理工大学学报JOURNALOFWUHANUNIVERSITYOFTECHNOLOGYVol.29No.8Aug.2007谢榕(,430074):依据二表法测量三相电路有功功率的原理,分析和讨论了在采用二表法测量三相三线制有功功率时,电路中各线电压和线电流之间的关系围绕有功功率表的读数等于该功率表电压线圈所接电压的有效值电流线圈所通过的电流的有效值以及电压与电流相位差余弦的乘积这一重要的概念,用实例说明在不同的接线情况下如何利用各电量的相量关系来确定所测的线电压线电流之间的相位差角方法简单实用:三相功率测量;二表法;相位差;相量图:TM131.4:A:16714431(2007)08014703ThreephaseCircuitPowerMeasuringwithTwowattmeterXIERong(CollegeofElectricalandElectronicEngineering,HuazhongUniversityofScienceandTechnology,Wuhan430074,China)Abstract:Accordingtotheprincipleofthreephasecircuitpowermeasuringwithtwowattmeter,therelationbetweenlinevoltageandlinecurrentwasanalysedinthispaperinadopttwowattmetermethodstomeasurethepowerofThreephaseThreewirecircuit.Withthisimportantconceptwhichthereadsofwattmeterwasequaltotheproductoftheeffectivevalueofthevoltageacrossthepotentialcoil,theeffectivevalueofthecurrentflowinginthecurrentcoil,andthecosineofthephaseanglebetweenthecurrentandthevoltage.Itwasspeciledwithsomeexamplestodeterminethephaseanglemeasuredbetweenlinevoltage,linecurrentindifferentconnection.Themethodwassimpleandpractical.Keywords:powermeasurementinthreephasesystems;twowattmetermethod;phasedifference;phasordiagram:20070510.:(1960),,.Email:[e-mail]:,,,,,,1,,,3:iA+iB+iC=0(iAiBiC),[1,2]11,AB,**,*C(3),(),()[1],1pp=pA+pB+pC=uAiA+uBiB+uCiCiA+iB+iC=0iC=-(iA+iB)p=iA(uA-uC)+iB(uB-uC)=iAuAC+iBuBC=p1+p2PP=1TT0pdt=1TT0[iAuAC+iBuBC]dt=UACIAcos1+UBCIBcos2=P1+P2,1uACiA,2uBCuBUACAC,IAA,UBCIB1,P1P2W1W2:,,,,,12,3:IAUAC-30IBUBC+30,P1+P2=UIcos(-30)+UIcos(+30)=3UIcos=P2,[2],,,21)()4,,,Rf[3],5,=KUIcos(u-i)[4]:K,U,I,(u-i),,,2)()C(6(a)),,,iA=-(iB+ic)iB=-(iA+ic),14820078AB,6(b)6(c),B,,,7,:2.5kW,cos=0.866380V,W1W2P1P2(1)IlP=3UlIlcosIl=P/3Ulcos=4.386A(2)IlUlUAN=220!0V,8,UAB=380!30VUBC=380!-90VUCB=380!90V=cos-10.866=30IA=4.386!-30A(3)9IAUAB:=60,P1=UABIAcos1=833.3,W1833.3W,,IC=4.3886!90A,ICUCB2=0,P2=UCBICcos2=1666.7,W21666.7W:2.5kW,,,,,,,3,P=UIcos,,,,,(下转第153页)149298:9,3,,5,,4,,,,,,[1],,,.[J].,2001,37(6):9498.[2],,.[J].,1999,(6):126132.[3],,.[J].,2000,14(1):811.[4],,,.[J].,2005,18(1):124128.[5].[D].:,2006.(上接第149页)[1].[M].4.:,1999.[2].[M].:,2000.[3]WilliamHHaytJr,KemmerlyJackE,DurbinStevenM.EngineeringCircuitAnalysis[M].SixthEdition,:,2002.[4],,,.[M].2.:,2006.153298,: