A 3_phase, 10 MVA/11KV Y connected, alterneter is protected by merz_ price circulating current system. The star point is earthed throug at risistance of 5 ohm. If CTs have rations of 1000/5 and The Realy is set to operate when their is overload with 30%. Determine 1) Determine The Percentage of each phase of stator winding which is protected if the reactance of the stator winding is 10% Per phase 2) Determine the minimum value of earthing risistine to Protect 85% of the winding negleet of The reactance of the stator winding in this case

A 3_phase, 10 MVA/11KV Y connected, alterneter is protected by merz_ price circulating current system. The star point is earthed throug at risistance of 5 ohm. If CTs have rations of 1000/5 and The Realy is set to operate when their is overload with 30%. Determine 1) Determine The Percentage of each phase of stator winding which is protected if the reactance of the stator winding is 10% Per phase 2) Determine the minimum value of earthing risistine to Protect 85% of the winding negleet of The reactance of the stator winding in this case

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 3.30MCQ

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