Problem-2 A star-connected, 3-phase, 10 MVA, 6.6 kV alternator is protected by a differential current protection scheme using 1000/5 A current transformer. The star point of the alternator is earthed through a resistance of 7.5 Q. If the minimum operating current for the relay is 0.5 A, Calculate the(% of each phase of the stator winding which is unprotected against earth- fault when the machine is operating at normal voltage.

Problem-2 A star-connected, 3-phase, 10 MVA, 6.6 kV alternator is protected by a differential current protection scheme using 1000/5 A current transformer. The star point of the alternator is earthed through a resistance of 7.5 Q. If the minimum operating current for the relay is 0.5 A, Calculate the(% of each phase of the stator winding which is unprotected against earth- fault when the machine is operating at normal voltage.

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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