第02章变压器

1、2IAX1U1E1E1I1mxa2E20U2I22E1U&1I&2I1E&2E&m&m&1I&2U&2I2E1E12绪论部分绪论部分AX1U1E1E10I1mxa2E20U1N2N1U10I01 10FN Im1E2E11E20U1011UI R与m1(0.1%0.2%)mm101 10fN i1sinmt 111sin(90 )mdeNNtdt 11114.4422mmmENEfN224.44mEjfN 114.44mEjfN 11101110101102NIEjj L IjI XI 111114.442NEjjfN 11111sin(90 )deNNtdt 111011110111ddUI

2、 REEI RNNdtdt2022dUENdt 11011110110111UI REEI RjI XEE 202UE1112220ENUkENU10miiiFeimimFeiiiiFeiFeI1EmFeIII11dieLdt 11Ej L IjI X X1FeFeEI R FeR2FeFeFepI R1UmI1E1R1jXIFeIFeRX1UmI1E1R1jXmRmjXmZ1()mmmmmEI ZIRjX mmmZRjXmRmjX()FemmmFeRjXZRjXRjX1U10()mII1E1R1jXmRmjXmmI1E2EFeII1E1U1mI R1mjI X1N2IAX1U1E1E11()

3、mLIII1mxa2E20U2I22E2NLZ1U1I11 1FN Im1E2E11E222UI R与平衡111UI R与平衡2I222FN ImF22ELZ12mFFF1 1221 mN IN IN I1 1220LN IN I11mLIII1LI1 1LN I2I22N I2222222222NIEjj L IjI XI 222224.442NEjjfN 22222sin(90 )deNNtdt 11111111()UI RjXEI ZE22222222()EI RjXUI ZU1111UI ZE ，2222EI ZU ，12EkE1 1221mN IN IN I ，1mmEI Z 22N

4、 I221 2N IN I221 2N IN I222211NIIINk22214.444.44mEEjfNjfN12222NEEkEN222222I RI R22222222IRRk RI22222222IXXk XI22222LLLIZZk ZI2222()kUk EI Z=2222222221kUkEI k ZEI ZUkk1111UI ZE ，2222EI ZU,12mIII ，12mmEEI Z 1U1I2I1E1R1jXmRmjX2R2jXmI2U2U2E1U1I1R1jX2jX2R2I1E1EmRmjXmILZ1U1I2U2I1N2N12m1U1I2U2I1N2Nm2E1E1R1

5、jXmRmjX2R2jX1LI1U1I2U2I1N1N2E1E1R1jXmRmjX2R2jX2ImI1U1I2U2I2E1E1R1jXmRmjX2R2jXmI1U1I2U2I12kRRRmRmjXmI12kjXjXjX1U12II 2UkRkjXkkkZRjXkjXkR2U2I222I R22jI X12EEmI1I2I1E11I R11jI X1m1U1111UEI Z 2222EUI Z 22LUI Z 1214.44 NmEEjf 1/mmIEZ 12mIII 2U2I2coskmZkFepkFepmZ11NUU10I0P1011(0.002 0.01)NmIIZZ110NmUZI221

6、01100mFeI RI RPp0210mPRI22mmmXZRkmZFep110020UIPU、 、120NUkUkNpkNpkZkZkU1kNIIkkNPp1kNmUUp Fe比正常运行小很多很小1kkNUZI21kNkNPRI22kkkXZR75234.575234.5KkCRR7522575225KkCRR227575kkCkCZRX kCuPp1212kRRR1212kXXXkU1kNII112kEU1R1jX2R2jXkru*kZku*kRkau*kXkkNkkkkkNNNNNZZI ZUZUuUZUUIAiBiABC0ABC 13t0018003600003A3B3C1A1B1C

7、01800360ttt0333cos3(120 )cos3BBtt 0333cos3(240 )cos3CCtt 333cos3cos3AAtt ABC1A3A1B3B3C1C0Ai0Bi0Ci3A3B3CABCXYZyzabCxabCxyzABCXYZm0itt0i00( )i t( ) t05i07i0i03i01i0it01i03i0i00103050103iiiiii030300303030030303sin3sin3(120 )sin3sin3(240 )sin3AmBmmCmmiItiItItiItItt0i0t0i13绕组接法决定绕组接法决定磁路饱和决定磁路饱和决定数学分解数学分

8、解0i133e1eett00ee1e133e由于由于 很弱，很弱， 也很小也很小 接近正弦。接近正弦。33e13eee1800KVA1800KVA及以下容量的变压器可采用此接法。及以下容量的变压器可采用此接法。一次一次23e23i23e0()i 正弦波()平顶波1()正弦波3()正弦波绕组绕组1()e正弦波13()e正弦波23()e正弦波23i23相互削弱相互削弱励磁电流励磁电流三次谐波三次谐波主磁通主磁通三次谐波三次谐波相电动势相电动势应用应用YyYy心式心式无无弱弱( (走漏磁路走漏磁路) )正弦正弦1800KVA1800KVA以上不用以上不用YyYy组式组式无无 强强( (走主磁路走主磁

9、路) )尖峰尖峰不用不用YNyYNy有有( (经中线经中线) )无无正弦正弦可用可用YynYyn有有( (经中线经中线) )无无正弦正弦可用可用Yd (Dy)Yd (Dy)有有( (中有中有) )可略去可略去接近正弦接近正弦可用可用=该物理量的实际值标幺值该物理量的基准值1U*1U1111NbNNUZZI2222NbNNUZZI有功、无功或容量线电压相电压线电流相电流电阻、电抗或阻抗NSNS1NU2NU1NU2NU1NI2NI1NI2NI111NNNUZI222NNNUZI2*22222211122NNNNRk RRRRRZZZZk*33llNNNUUUUUUUU*cos33cos3llNNN

10、U IU IPPPSSS*kkNkkkNNNZZ IUZUZUU*0.040.14kZ *00.0020.01I *111NIII*11I *11I *11I *1I2*11NkNkkNkNkNNNNIRIRPPRSUIU21*2* 2*1111()()kkNCuCukNNNNNI RIR IPPIRSUIIU*N*4.44()4.44NmNmNNmmmfNUEEUUfN 取*0I*mZ*10*11101011mNmNNNNZUIZZUIIII*kZ*kI*1*11111NkkkNNkNUZIZ IIZU20000NSkVA50Hz1212711NNUUkVkV015 C试验名称电压电流功率备

11、注开路试验短路试验11kV9.24kV45.5A157.5A47kW129kW电压加在低压侧电压加在高压侧12XX01(75)3.9CR1120000157.5127NNNSIAU22200001818.211NNNSIAU1212711.54511NNUkU32222()20322220()22202222311221111 1011.5453222345.547 1011.545302645.5322233026320819240129 1058.675.2157.5157.5mmmmmmmkkkkkkUZk ZkIPRk RkIXZRUPZRIIX低压低压222258.675.258.4

12、4kkkZR075 C000(75)2222(75)(75)234.5755.26.451234.5156.45158.4458.79kCkkCkCRZRX00001(75)2(75)(75)1(75)123.92.551129.223026320812CCkCCkmmRRRRXXXRX1U1I2U2I01(75)3.9CR129.22jXj3026mR 32081mjXj229.22jXjmI02(75)2.551CR33333311112()*22()*2112()*21818.2 241.7639.9611 1018157.5 32223127 10157.5 3026127 10157

13、.5 3218.2 22.73.75211 101818.2 240.081127 10711 10NmmNNmmNNmmNNmNNmNNmNIZUIRUIZZUIIXRRUIXXUU低压低压低压39.7900300331(75)*(75)11(75)*(75)1*11157.5 58.790.0729127 10157.5 6.4510.008127 10157.5 58.440.0725127 10NkCkCNNkCkCNNkkNIZZUIRRUIXXU*11I *kZ3333*22*2229.24 100.0727127 10129 100.0064520000 100.07270.00

14、6450.0725kkkkkkkkkkkUZUIPRPIXZR*kR0*(75)kCR00*(75)(75)0.0080.0729kCkCRZ1000NSkVA12106.3NNUUkVkV04.9PkW15kPkW075 C11100057.73533 10NNNSIAU03111013022102222311111132(75)110 10200035%35%57.7354.9 1019633(5%57.735)200019619905.5%5.5% 10 105.53357.73515 1033 57NNmNmmmmkkNkkNNkkCNUUZIIPRIXZRUUUZIIIPRI0222

15、22(75)1.5.7355.51.55.29kkkCXZR311110 1010033 57.735NbNUZI00*1*11*1(75)*(75)1120002010019619901.9619.91001005.50.0551001.55.290.0150.0529100100mmbmmmmbbkkbkCkkkCbbZZZRXRXZZZZZRXRXZZ00*001*2*22101010*2*222*1*2(75)11*2*222(75)14.9201.960.051000 0.05201.9619.90.055150.0550.0151110000.0550.0150.0529Nmmmm

16、mkkkNkkkCkkNkkkCPP SUZRIIIXZRUPP SPZRIISXZR1.000.750500.25*2U*2I2cos0.8()超前2cos12cos0.8()滞后0.250500.751.00011222,cos,()NUUUf I常数2022212221100%100%100%NNNNNUUUUUUuUUU *2211uUU u1NU2NU2NU2U22()NUU2NU2U*121NkUUI Z *1221NUUABABU uAB 12*12II K*2U*11NU*1kI R*1kjI X2ABCD*1NU*2U*LZ*12II *kR*kjXuAB 12*12II K

17、*2U*11NU*1kI R*1kjI X2ABCD12cos()kkUABI Z12222(coscossinsin)(cossin)kkkkkI ZRX22(cossin)kkURX 时， 称为额定电压调整率，标志着变压器的输出电压的稳定程度。1U20202 变压器的短路阻抗 越小， 也越小，供电电压越稳定。KZUk2N0i1u1N01U1102sinUUtak2N0i1N1u101102sintdNi RUtadt101tNiL1111012sinttdRNNUtadtL1L0i解常系数非齐次微分方程得：解常系数非齐次微分方程得：110rtLtmSintace 101190Ltgr磁通与

18、电源电压的相位差磁通与电源电压的相位差 110rtLtmCostace 00t设合闸时（设合闸时（t=0t=0），铁心中没有剩磁（），铁心中没有剩磁（ ）：）：1.1.当电源电压初相位角当电源电压初相位角 时合闸：时合闸： 00900cos90sintmmtt 合闸后就进入稳定状态，不发生瞬整过程合闸后就进入稳定状态，不发生瞬整过程 t1u02.2.当电源电压初相位角当电源电压初相位角 时合闸：时合闸：00011cosrtLtmmte 自由分量是直流指数衰减量，自由分量是直流指数衰减量， 时时最大，当最大，当 时，稳态分量与暂态分量时，稳态分量与暂态分量相加可达相加可达2m0t m0180tt0pht1ut0pht1u 当已知变压器空载接通电源其磁通随时当已知变压器空载接通电源其磁通随时间变化