3 d3发生短路时流过断路2Р(1)最大运行方式正序短路电流РXff3=XdT+XL=0.18255+0.5444=0.72695РId3·max*=E/Xff3=1.05/0.72695≈1.4444РId3·max=Id3·max*IB=1.4444×0.502≈0.725KAР(2)最小运行方式两相短路正序短路电流РXff3=Xd1+XT1+XL=0.4224+0.3050+0.5444=0.9996РIf(2)*=1.732E/2Xff1=1.732×1.05/2×0.9996=0.9097РIf(2)=If(2)*IB=0.9097×0.502=0.4567KAР(3)最大运行方式两相短路零序短路电流,如图3.2.3示Р图3.2.3短路等值电路РXTL4(0)=(XL4(0) +XT8)×(XL3(0) +XT)/(XL4(0) +XT8+XL3(0) +XT)Р =(0.2268+0.6405)×(0.8166+0.0781)/(0.2268+0.6405+0.8166+0.0781)Р =0.4404РXTL2(0) =(XL2(0)+XTC)×XTB/(XL2(0)+XTC+XTB)Р =(0.363+0.2401)×0.2401/(0.363+0.2401+0.2401)Р =0.1717РXBL(0) =XTL4(0)×XTL2(0)/(XTL4(0)+XTL2(0))=0.4404×0.1717/(0.4404+0.1717)Р =0.1235РXff3(0)=XL1(0)+XBL(0)=0.4536+0.1235=0.5771РIff3(0)*=E(0)/Xff3(0)=1.05/0.5771=1.819РIff3(0)=Iff3(0)*IB=1.89×0.502=0.913KAР4.2.4 d4点发生短路时流过断路1Р(1)最大运行方式正序短路电流
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