86变压器

第三章变压器3.7三相变压器three-phasetransformer3.7.1磁路系统magneticpasssystem一、组式磁路变压器group-typemagneticpasstransformer二、心式磁路变压器core-typemagneticpasstransformer特点是：三相磁路彼此无关联。Characteristic,norelationshipamongthree-phasemagneticpasses特点是：三相磁路彼此有关联。Characteristic,three-phasemagneticpassesarerelating.1W2Ww1V2Vv1U2Uu1U2U1u2u1V2V1v2v1W2W1w2wuvw第三章变压器3.7.2电路系统circuitsystem一、变压器的端头标号endtapsoftransformer绕组名称nameofwindings单相变压器single-phasetransformer三相变压器three-phasetransformer中性点neutralpoint首端headend末端bottomend首端headend末端bottomend高压绕组HVwindingU1U2U1、V2、W1U2、V2、W2N低压绕组LVwindingu1u2u1、v1、w1u2、v2、w2n中压绕组IVwindingU1mU2mU1m、V1m、W1mU2m、V2m、W2mNm第三章变压器二、单相变压器的极性polarityofsingle-phasetransformer*1U2U1u2u*1U2U1u2u1U2U1u2u)I,I(I/I012连接组别为)I,I(I/I66连接组别为一、二次绕组的同极性端同标志时，一、二次绕组的电动势同相位。Whenthesamepolarityendsofprimaryandsecondarywindingsareinthesamesigns,theelectromotiveforceofprimaryandsecondarywindingsareinthesamephases.**1u2u1U2U1u2u**1U2U**1U2U1u2u一、二次绕组的同极性端异标志时，一、二次绕组的电动势反相位。Whenthesamepolarityendsofprimaryandsecondarywindingsareindifferentsigns,theelectromotiveforceofprimaryandsecondarywindingsareinoppositephases.VectorgroupisI/I-12(I,IO)VectorgroupisI/I-6(I,I6)第三章变压器三、三相变压器的连接组别vectorgroupofthree-phasetransformer连接组别：反映三相变压器连接方式及一、二次线电动势（或线电压）的相位关系。Vectorgroup,reflectsconnectingmodeofthree-phasetransformerandphaserelationshipbetweenprimarylineelectromotiveforceandsecondarylineelectromotiveforce(linevoltage).三相变压器的连接组别不仅与绕组的绕向和首末端标志有关，而且还与三相绕组的连接方式有关。Vectorgroupofthree-phasetransformerisnotonlyrelatedtothedirectionofwindingsandthesignsofheadandbottomends,butalsotheconnectingmodeofthree-phasewindings.理论和实践证明，无论采用怎样的连接方式，一、二次侧线电动势（可电压）的相位差总是300的整数倍。因此可以采用时钟表示法——作为时钟的分针，指向12点，作为时钟的时针，其指向的数字就是三相变压器的组别号。组别号的数字乘以300，就是二次绕组的线电动势滞后于一次侧电动势的相位角。Itisprovedbytheoryandpractice,nomatterwhatconnectingmodeisadopted,thephasedifferenceoftheelectromotiveforce(voltage)atthesidesofprimaryandsecondarylinesisalwaysintegraltimesof300.So,clockrepresentationcanbeadopted.Whentheminutehandpointsto12,thenumberwhichthehourhandpointstoisthegroupnumberofthree-phasetransformer.Thenumberofgroupnumbermultiplying300isthephaseanglewhichlineelectromotiveforceofsecondarywindinglagstheelectromotiveforceatthefirstside.UVEuvE第三章变压器连接组别可以用相量图来判断：vectorgroupcanbejudgedbyvectordiagram若高压绕组三相标志不变，低压绕组三相标志依次后移，可以得到Y,y4、Y,y8连接组别。Ifthree-phasesignsofHVwindingarenotchanging,three-phasesignsofLVwindingmovebehindinturns,itcangetY,y4,andY,y8vectorgroup.1、Y，y连接UVEuvE同名端在对应端，对应的相电动势同相位，线电动势和也同相位，连接组别为Y，y0。endswiththesamenameareinthecorrespondingends,thephasesofthecorrespondingelectromotiveforcesarethesame,thesumoflineelectromotiveforcesareinthesamephase,vectorgroupisY,Y0.同理，若异名端在对应端，可得到Y，y6、Y,y10和Y,y2连接组别。Asthesame,ifendswithdifferentnamesareinthecorrespondingends,itcangetY,y6,andY,y10,andY,y2vectorgroup.第三章变压器若高压绕组三相标志不变，低压绕组三相标志依次后移，可以得到Y,d3、Y,d7连接组别。Ifthree-phasesignsofHVwindingarenotchanging,three-phasesignsofLVwindingmovebehindinturns,itcangetY,d3,andY,d7vectorgroup.2、Y，d连接-11Y,dconnecting-11UVEuvE同名端在对应端，对应的相电动势同相位，线电动势和相差3300，连接组别为Y，d11。Endswiththesamenameareinthecorrespondingends,thecorrespondingphaseelectromotiveforcesareinthesamephase,thesumoflineelectromotiveforcesdiffer3300,thevectorgroupisY，d11.同理，若异名端在对应端，可得到Y，d5、Y,d9和Y,d1连接组别。Asthesame,ifendswithdifferentnamesareinthecorrespondingends,itcangetY，d5,andY,d9,andY,d1vectorgroup.第三章变压器若高压绕组三相标志不变，低压绕组三相标志依次后移，可以得到Y,d5、Y,d9连接组别。Ifthree-phasesignsofHVwindingarenotchanging,three-phasesignsofLVwindingmovebehindinturns,itcangetY,d5andY,d9vectorgroup.3、Y，d连接-1Y，dconnecting-1UVEuvE同名端在对应端，对应的相电动势同相位，线电动势和相差300，连接组别为Y，d1。endswiththesamenameareinthecorrespondingends,thecorrespondingelectromotiveforcesareinthesamephase,thesumoflineelectromotiveforcesdiffer300,vectorgroupisY，d1.同理，若异名端在对应端，可得到Y，d7、Y,d11和Y,d3连接组别。Asthesame,ifendswithdifferentnamesareinthecorrespondingends,itcangetd7,Y,d11andY,d3vectorgroup.第三章变压器总之，对于Y，y（或D，d）连接，可以得到0、2、4、6、8、10等六个偶数组别；而Y，d（或D，y）连接，可以得到1、3、5、7、9、11等六个奇数组别。Inall,fortheconnectionofY,Y(orD,d),itcanget0,2,4,6,8,10andetcsixevennumbergroup;whiletheconnectionofY,d(orD,y),itcanget1,3,5,7,9,11andetcsixoddnumbergroup.变压器的连接组别很多，为了便于制造和并联运行，国家标准规定，Y，yn0、Y，d11、YN，d11、YN，y0和Y，y0连接组为三相双绕组电力变压器的标准连接组别。Vectorgroupsoftransformerareplenty,forconvenientmanufactureandparalleloperation,nationalstandardregulates,Y，yn0;Y，d11;YN，d11;YN，y0andY，y0vectorgroupsarethestandardvectorgroupsofthree-phasedoublewindingselectricpowertransformer.其中前三种最为常用：Y,yn0连接的二次绕组可以引出中线，成为三相四线制，用作配电变压器时可兼供动力和照明负载。Y,d11连接用于低压侧电压超过400V的线路中。YN,d11连接主要用于高压输电线路中，使电力系统的高压侧可以接地。Thereinto,theformerthreekindsaremostcommonlyused.ThesecondarywindingofY,yn0connectingcanleadoutmid-wire,formthree-phaseandfour-wiresystem,andbeusedforpowerdistributiontransformertosupplydynamicandlightingload.Y,d11connectingisusedinthewireswhichthevoltageatlowsideishigherthan400v.YN,d11connectingismainlyusedinHVpowertransmissionlines,andtomaketheHVsideofelectricpowersystembegrounding.第三章变压器3.7.3磁路系统和绕组连接方式对电动势波形的影响theinfluencetoelectricpotentialwavefromexcitationpasssystemandwindingc