A star connected 3 phase, 15 MVA. 12kV alternator has a phase reactance of 10 % it is protected by Merz-Price circulating current scheme which is set to operate for fault current not less than 200 A. Calculate the value of earthing resistance to be provided in order to ensure that only 15 % of the alternator winding remains unprotected.

A star connected 3 phase, 15 MVA. 12kV alternator has a phase reactance of 10 % it is protected by Merz-Price circulating current scheme which is set to operate for fault current not less than 200 A. Calculate the value of earthing resistance to be provided in order to ensure that only 15 % of the alternator winding remains unprotected.

Power System Analysis and Design (MindTap Course List)

6th Edition

ISBN:9781305632134

Author:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Chapter3: Power Transformers

Section: Chapter Questions

Problem 3.10P: A single-phase step-down transformer is rated 13MVA,66kV/11.5kV. With the 11.5 kV winding...

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