A 4 MVA, 66/13.2 Kv, 50 Hz. Delta star connected Three phase transformer has a primary resistance of (20 ohm) per phase and secondary resistance of (0.4 ohm) per phase. If the percentage impedance drop is (4%), find(): The percentage regulation at (0.75) of full load at (0.6) pif lagging (2) The range of p.f which gives negative regulation.

A 4 MVA, 66/13.2 Kv, 50 Hz. Delta star connected Three phase transformer has a primary resistance of (20 ohm) per phase and secondary resistance of (0.4 ohm) per phase. If the percentage impedance drop is (4%), find(): The percentage regulation at (0.75) of full load at (0.6) pif lagging (2) The range of p.f which gives negative regulation.

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 3.31P

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