1. Consider a single-phase 11 KV/0.11 kV 1.1 MVA transformer protected by percentage differential protection. CTs with 5 A secondaries are used. It is known that the magnetizing currents of the two CTs, for maximum external fault current, differ by 0.5 A. Assuming no other source of error and a minimum pick-up of 0.01 A, find the minimum percentage bias setting so that the scheme remains stable on maximum external fault current.

1. Consider a single-phase 11 KV/0.11 kV 1.1 MVA transformer protected by percentage differential protection. CTs with 5 A secondaries are used. It is known that the magnetizing currents of the two CTs, for maximum external fault current, differ by 0.5 A. Assuming no other source of error and a minimum pick-up of 0.01 A, find the minimum percentage bias setting so that the scheme remains stable on maximum external fault current.

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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