南华大学电气工程及其自动化专业课程设计
If(2)*=1.732E/4Xff1=1.732×1.05/4×0.31865=1.429 流过断路器1、2、3、4、5和6的二相短路电流为： If(2)=If(2)*IB=1.429×0.502=0.7163KA (3)最大运行方式两相短路零序短路电流
图3.2.6短路等值电路
X2(0) =(XL4(0)+XT8)×XTC/(XL4(0)+XT8+XTC)=0.2061 X1(0) =(XL1(0)+XT)×XTB/(XL1(0)+XT+XTB) =0.1654 Xff5(0) =(XL2(0)+X1(0))×X2(0)/(XL2(0)+X1(0))+X2(0))=0.1483 Iff6(0)*=E(0)/Xff5(0)=1.05/0.1483=7.082 Iff6(0)=Iff5(0)*IB=7.082×0.502=3.555KA
3.2.7 d6点发生短路时流过断路器1
(1)最大运行方式正序短路电流
其中：Xff7=XdT+XL1+XL2+XL4=0.18255+0.1512+0.121+0.0756=0.53035
Id6·max*=E/Xff7=1.05/0.53035≈1.9798 Id7·max=Id7·max*IB=1.9798×0.502≈0.994KA (2)最小运行方式两相短路正序短路电流
X2 =(XL1+XL2)×XL3/( XL1+XL2+ XL3)= XL3/2=0.1361 Xff2=Xd1+X2+XL4=0.18255+0.1361+0.0756=0.39425 If(2)*=1.732E/4Xff1=1.732×1.05/4×0.39425=1.1532 流过断路器1、2、3、4、5、6和7的短路电流为： If(2)=If(2)*IB=1.1532×0.502=0.5789KA If(2)=If(2)*IB=1.1532×0.502=0.5789KA (3)最大运行方式两相短路零序短路电流
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南华大学电气工程及其自动化专业课程设计
图3.2.7短路等值电路
X1(0) =(XL1(0)+XT)×XTB/(XL1(0)+XT+XTB)
=(0.4536+0.0781)×0.2401/(0.4536+0.0781+0.2401) =0.1654
X3(0) =(XL2(0)+X2(0))×XTC/(XL2(0)+X2(0)+XTC)
=(0.363+0.1654)×0.2401/(0.363+1654+0.2401) =0.1651
Xff7(0) =(XL4(0)+X3(0))×XT8/(XL4(0)+X3(0)+XT8)
=(0.8166+0.1651)×0.6405/(0.8166+0.1651+0.6405) =0.3876
Iff7(0)*=E(0)/Xff7(0)=1.05/0.3876=2.709 Iff7(0)=Iff7(0)*IB=2.709×0.502=1.36KA
3.2.8 d6点发生短路时流过断路器2
(1)最大运行方式正序短路电流
其中：Xff8=XdT+XL3+XL4=0.18255+0.2722+0.0756=0.53035
Id8·max*=E/Xff8=1.05/0.53035≈1.9798 Id8·max=Id8·max*IB=1.9798×0.502≈0.994KA (2)最小运行方式两相短路正序短路电流
X2 =(XL1+XL2)×XL3/( XL1+XL2+ XL3)= XL3/2=0.1361 Xff2=Xd1+X2+XL4=0.18255+0.1361+0.0756=0.39425 If(2)*=1.732E/4Xff1=1.732×1.05/4×0.39425=1.1532 流过断路器1、2、3、4、5、6和7的短路电流为：
If(2)=If(2)*IB=1.1532×0.502=0.5789KA
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南华大学电气工程及其自动化专业课程设计
(3)最大运行方式两相短路零序短路电流
图3.2.8短路等值电路
X4(0)=(XL2(0) +XTB)×(XL3(0) +XT)/(XL2(0) +XTB+XL3(0) +XT)
=(0.363+0.2401)×(0.8166+0.0781)/(0.363+0.2401+0.8166+0.0781) =0.3603
X5(0) =X4(0)×XTC/(X4(0)+XTC)=0.3603×0.2401/(0.3603+0.2401)=0.1441 Xff8(0) =(XL4(0)+X5(0))×XT8/(XL4(0)+X5(0)+XT8)
=(0.2268+0.1441)×0.6405/(0.2268+0.1441+0.6405) =0.2349
Iff8(0)*=E(0)/Xff8(0)=1.05/0.3882=4.4703 Iff8(0)=Iff8(0)*IB=4.4703×0.502=2.244KA
3.2.9 d8点发生短路时流过断路器1
(1)最大运行方式正序短路电流 短路电路等效图为：
图3.2.9(a)正序短路电路图
图3.2.9(b)正序短路电路图
其中：XT45=XT4×XT5/(XT4+XT5)=XT4/2=0.4802/2=0.2401
Xff9=XdT+XL1+XT45=0.18255+0.1512+0.2401=0.57385
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南华大学电气工程及其自动化专业课程设计
Id9·max*=E/Xff9=1.05/0.57385≈1.8297 Id9·max=Id9·max*IB=1.8297×0.502≈0.919KA (2)最小运行方式两相短路正序短路电流
图3.2.9(c)短路等值电路
X3 =(XL3+XL2)×XL1/( XL1+XL2+ XL3)
=(0.2722+0.121)×0.1512/(0.2722+0.121+ 0.1512) =0.1156
Xff2=Xd1+X3+XTB=0.18255+0.1156+0.2401=0.5382 If(2)*=1.732E/2Xff1=1.732×1.05/2×0.5382=1.690 If(2)=If(2)*IB=1.690×0.502=0.8481KA
If(2)1*= If(2)*×XL1/( XL1+XL2+ XL3)=1.690×0.1512/(0.2722+0.121+ 0.1512)
=0.2356
流过断路器1、4、5、6的的短路电流为： If1(2)=If(2)*IB=0.847×0.502=0.425KA 流过断路器2、3的的短路电流为：
If2(2)=If(2)*－If1(2)= 0.8481KA-0.2356KA=0.6125KA (3)最大运行方式两相短路零序短路电流
图3.2.9(d)短路等值电路
X6(0) =(XL4(0)+XT8)×XTC/(XL4(0)+XT8+XTC)
=(0.2268+0.6405)×0.2401/(0.2268+0.6405+0.2401) =0.188
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南华大学电气工程及其自动化专业课程设计
X7(0 )=(XL2(0) +X6(0))×(XL1(0) +XT)/(XL2(0) +X6(0)+XL1(0) +XT)
=(0.363+0.188)×(0.8166+0.0781)/(0.363+0.188+0.8166+0.0781) =0.3410
Xff9(0) =XTB+X7(0)=0.2401+0.341=0.5811 Iff9(0)*=E(0)/Xff9(0)=1.05/0.5811=1.8069 Iff9(0)=Iff9(0)*IB=1.8069×0.502=0.907KA
3.2.10 d8点发生短路时流过断路器2
(1)最大运行方式正序短路电流 短路电路等效图为：
图3.2.10(a)短路电路图
其中：Xff10=XdT+XL1+XT45=0.18255+0.2722+0.121+0.2401=0.81585
Id10·max*=E/Xff10=1.05/0.81585≈1.287 Id10·max=Id10·max*IB=1.287×0.502≈0.646KA (2)最小运行方式两相短路正序短路电流
图3.2.10(b)短路电路图
X3 =(XL3+XL2)×XL1/( XL1+XL2+ XL3)
=(0.2722+0.121)×0.1512/(0.2722+0.121+ 0.1512) =0.1156
Xff2=Xd1+X3+XTB=0.18255+0.1156+0.2401=0.5382 If(2)*=1.732E/2Xff1=1.732×1.05/2×0.5382=1.690 If(2)=If(2)*IB=1.690×0.502=0.8481KA If(2)1*= If(2)*×XL1/( XL1+XL2+ XL3)
=1.690×0.1512/(0.2722+0.121+ 0.1512) =0.2356
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110kv继电保护课程设计(1) - 图文
