Example 8.3A 25 MVA, 11 kV generator with X4" = 20% is connected through a transformer to abus that supplies three identical motors as shown in the following figure. Each motorhas Xa" = 25% and X4' = 30% on a base of 5 MVA, 6.6 kV. The three-phase rating ofthe step up transformer is 25 MVA 11/66 kV with a leakage reactance of 10% and thatof the step down transformer is 25 MVA, 66/6.6 kV with a leakage reactance of 10%.The bus voltage of the motors is 6.6 kV when a three-phase fault occurs at the point F.For the specified fault, calculate the subtransient current at the fault point. Given thereactance of transmission line is 15% on a base 25 MVA, 66 kV. Choose a system baseof 25 MVA and 11 kV at generator side and assume that the system is operating on noload.MIT2Xiine = 15%M225 MVA25 MVA11/66 kV66/6.6 kVM3X=10%X= 10%5 MVA6.6 kVX"= 25%; X' = 30%

Answered: Image /qna-images/answer/d27e0ad8-fcbb-4063-a337-fe71288da818.jpg

Example 8.3 A 25 MVA, 11 kV generator with X4" = 20% is connected through a transforme bus that supplies three identical motors as shown in the following figure. Each has Xa" = 25% and X4' = 30% on a base of 5 MVA, 6.6 kV. The three-phase rat the step up transformer is 25 MVA 11/66 kV with a leakage reactance of 10% of the step down transformer is 25 MVA, 66/6.6 kV with a leakage reactance o The bus voltage of the motors is 6.6 kV when a three-phase fault occurs at the For the specified fault, calculate the subtransient current at the fault point. Give reactance of transmission line is 15% on a base 25 MVA, 66 kV. Choose a syst of 25 MVA and 11 kV at generator side and assume that the system is operatin load. MI T2 Xiine = 15% M2 25 MVA 25 MVA 11/66 kV 66/6.6 kV M3 X=10% X= 10% 5 MVA 6.6 kV X"= 25%; X' = 30%

Example 8.3 A 25 MVA, 11 kV generator with X4" = 20% is connected through a transforme bus that supplies three identical motors as shown in the following figure. Each has Xa" = 25% and X4' = 30% on a base of 5 MVA, 6.6 kV. The three-phase rat the step up transformer is 25 MVA 11/66 kV with a leakage reactance of 10% of the step down transformer is 25 MVA, 66/6.6 kV with a leakage reactance o The bus voltage of the motors is 6.6 kV when a three-phase fault occurs at the For the specified fault, calculate the subtransient current at the fault point. Give reactance of transmission line is 15% on a base 25 MVA, 66 kV. Choose a syst of 25 MVA and 11 kV at generator side and assume that the system is operatin load. MI T2 Xiine = 15% M2 25 MVA 25 MVA 11/66 kV 66/6.6 kV M3 X=10% X= 10% 5 MVA 6.6 kV X"= 25%; X' = 30%

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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