A 500 kVA, 6.6 kV star connected alternator has a synchronous reactance of 1.0 2 per phase and negligible resistance. The differential relay operates if the out of balance current through it exceeds 30% of the normal full load current of the alternator. The star point of the alternator is earthed through a resistance of 5 2. What percent of the stator winding is left unprotected? Show that the effect of the alternator reactance can be neglected.

A 500 kVA, 6.6 kV star connected alternator has a synchronous reactance of 1.0 2 per phase and negligible resistance. The differential relay operates if the out of balance current through it exceeds 30% of the normal full load current of the alternator. The star point of the alternator is earthed through a resistance of 5 2. What percent of the stator winding is left unprotected? Show that the effect of the alternator reactance can be neglected.

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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