A 39.6 kV, 6 MVA star connected alternator has a reactance of 1.5 ohm per phase and negligible resistance. Merz-Price protection scheme is used which operates when the out of balance current exceeds 35% of the full load current. The neutral of the generator is grounded through a resistance of 16 ohms. Determine the proportion of the winding which remains unprotected against earth fault. Show that the effects of the alternator reactance can be ignored.

A 39.6 kV, 6 MVA star connected alternator has a reactance of 1.5 ohm per phase and negligible resistance. Merz-Price protection scheme is used which operates when the out of balance current exceeds 35% of the full load current. The neutral of the generator is grounded through a resistance of 16 ohms. Determine the proportion of the winding which remains unprotected against earth fault. Show that the effects of the alternator reactance can be ignored.

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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