华北电力大学电机学课件(全3) - 图文

变比：主磁通在三个绕组感应主磁电势之比等于变比，总共三个变比。?U1N1N1U1k12??N2U2k13N1U1??N3U3?U2N2?U3N3k23N2U2??N3U3参数归算（归算到一次侧）：11'???,I???III233k12k13'2''????U2?k12U2,U3?k13U3X'22'2?k12X22,2'32X?k13X332'332R?k12R2,R?k13R3?X21??Ms21,?N1N1?s21X??X21?N1N2?s21'12N1?s21Ms21??N1N2?s21i2?X?k12X12'31'12X?k13X13?X,'13X?k12k13X23?X'23'32归算后的四个基本方程：''''??????U1?I1R1?jI1X11+jI2X21+jI3X31?E01'''''''''???????U2?I2R2?jI2X22+jI1X12+jI3X32?E02…①…②…③…④'''''''''???????U3?I3R3?jI3X33+jI1X13+jI2X23?E03''???I1?I2?I3?0''???①式减去②式，再用④式中I3??I1?I2，可得：''''????U1?(?U2)?I1R1?jI1(X11+X23-X12-X31)'''''''???I2R2?jI2(X22+X31-X23-X12)''???①式减去③式，再用④式中I2??I1?I3，可得：''''????U1?(?U3)?I1R1?jI1(X11+X23-X12-X31)'''''''???I3R3?jI3(X33+X12-X31-X23)最后可简写为：?U???U??I?Z+I?Z1'3'3'3'''????U1??U2?I2Z2+I1Z111