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(1): The percentage regulation at (0.75) of full load at (0.6) p.f 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(1): The percentage regulation at (0.75) of full load at (0.6) p.f 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 3.28MCQ

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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(1): The percentage regulation at (0.75) of full load at (0.6) p.f lagging.(2):The range of p.f which gives negative regulation.