"A star-connected, 3-phase, 10 MVA, 6.6 kV alternator has a per phase reactance of 15%. It is protected by differential current protection scheme which is set to operate for fault currents not less than 250 A. Calculate the value of following to be provided in order to ensure that only 12% of the alternator winding remains unprotected. (i) Full load current (in Amp) (ii) Reactance (in Ohm) offered by the unprotected part of the alternator winding (iii) Impedance (in Ohm) offered to fault by 12 percent winding (iv) What change will occur to earthing resistance if the fault current decreases to 200 A while all conditions remain same?"

"A star-connected, 3-phase, 10 MVA, 6.6 kV alternator has a per phase reactance of 15%. It is protected by differential current protection scheme which is set to operate for fault currents not less than 250 A. Calculate the value of following to be provided in order to ensure that only 12% of the alternator winding remains unprotected. (i) Full load current (in Amp) (ii) Reactance (in Ohm) offered by the unprotected part of the alternator winding (iii) Impedance (in Ohm) offered to fault by 12 percent winding (iv) What change will occur to earthing resistance if the fault current decreases to 200 A while all conditions remain same?"

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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