Q3. In a % differential scheme, figure shown below, the two CTs have nominal ration of 100:1. The CT errors for a through fault current of 5000 A are as following: CT1 CT2 Ratio error: 10% 10% Phase angle error: 5% -5% Compute following: i) The spill current of the OC relay in the spill path. ii) If the relay is 50% biased, examine whether relay will trip or remain stable / CT, CB CT C.B. Egu inder ieclion No

Q3. In a % differential scheme, figure shown below, the two CTs have nominal ration of 100:1. The CT errors for a through fault current of 5000 A are as following: CT1 CT2 Ratio error: 10% 10% Phase angle error: 5% -5% Compute following: i) The spill current of the OC relay in the spill path. ii) If the relay is 50% biased, examine whether relay will trip or remain stable / CT, CB CT C.B. Egu inder ieclion No

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

Chapter7: Symmetrical Faults

Section: Chapter Questions

Problem 7.1MCQ

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