A three-phase synchronous generator is connected to a step-up 3¢ transformer T1, which isconnected to a 60 km transmission line. At the far end of the line, a step-down transformerbank T2 is connected. The secondary of T2 supplies two synchronous motor loads M1 andM2. The ratings of the equipment are as follows:10 MVA,12 MVA, 13.8/138 kV,12 MVA,4 MVA,3 MVA,X = 30%,X = 10%,X = 9%,X = 25%,X = 30%,X = 0.3 2/kmGen:13.8 kV,wyedelta-wyewye-deltaT1:138/12 kV,12 kV,12 kV,138 kV,T2:M1:wyeM2:wye%3|T-line:(a) Draw the per-phase equivalent circuit of the system showing all reactances inand the base voltages used at various parts of the network. Choose the generator ratingsas bases in the generator circuit.perunit(b) For a three-phase fault on the low-voltage terminals of transformer T2, calculate thesteady-state short-circuit current magnitude in amperes supplied by the generator as-suming that all internal voltages are 1.020° pu. Ignore the motor contributions to thefault current for now.

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A three-phase synchronous generator is connected to a step-up 3¢ transformer T1, which is connected to a 60 km transmission line. At the far end of the line, a step-down transformer bank T2 is connected. The secondary of T2 supplies two synchronous motor loads M1 and M2. The ratings of the equipment are as follows: 10 MVA, 13.8 kV, 12 MVA, 13.8/138 kV, 138/12 kV, 12 kV, 12 kV, 138 kV, X = 30%, X = 10%, X = 9%, X = 25%, X = 30%, X = 0.3 N/km Gen: wye T1: T2: M1: 12 MVA, 4 MVA, 3 MVA, delta-wye wye-delta wye M2: wye T-line: %3| (a) Draw the per-phase equivalent circuit of the system showing all reactances in and the base voltages used at various parts of the network. Choose the generator ratings as bases in the generator circuit. per unit (b) For a three-phase fault on the low-voltage terminals of transformer T2, calculate the steady-state short-circuit current magnitude in amperes supplied by the generator as- suming that all internal voltages are 1.0° pu. Ignore the motor contributions to the fault current for now.

A three-phase synchronous generator is connected to a step-up 3¢ transformer T1, which is connected to a 60 km transmission line. At the far end of the line, a step-down transformer bank T2 is connected. The secondary of T2 supplies two synchronous motor loads M1 and M2. The ratings of the equipment are as follows: 10 MVA, 13.8 kV, 12 MVA, 13.8/138 kV, 138/12 kV, 12 kV, 12 kV, 138 kV, X = 30%, X = 10%, X = 9%, X = 25%, X = 30%, X = 0.3 N/km Gen: wye T1: T2: M1: 12 MVA, 4 MVA, 3 MVA, delta-wye wye-delta wye M2: wye T-line: %3| (a) Draw the per-phase equivalent circuit of the system showing all reactances in and the base voltages used at various parts of the network. Choose the generator ratings as bases in the generator circuit. per unit (b) For a three-phase fault on the low-voltage terminals of transformer T2, calculate the steady-state short-circuit current magnitude in amperes supplied by the generator as- suming that all internal voltages are 1.0° pu. Ignore the motor contributions to the fault current for now.

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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