Three 11 kV; 20 MVA 3 plase synchronous generators are connected to common set of bus bars. Each machine has a reactance to positive sequence currents of 20%. The reactances to negative and zero sequence currents are 15% and 30% respectively. If an earth fault occurs on one busbar determine the fault current. (a) If all the generator neutrals are solidly earthed. (b) If only one of the generator neutral is solidly earthed and the others are isolated. (c) If one of the generator neutrals is earthed through a resistance of 05 N and the others are isolated.

Three 11 kV; 20 MVA 3 plase synchronous generators are connected to common set of bus bars. Each machine has a reactance to positive sequence currents of 20%. The reactances to negative and zero sequence currents are 15% and 30% respectively. If an earth fault occurs on one busbar determine the fault current. (a) If all the generator neutrals are solidly earthed. (b) If only one of the generator neutral is solidly earthed and the others are isolated. (c) If one of the generator neutrals is earthed through a resistance of 05 N and the others are isolated.

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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