In an open-circuit test of a 10KVA 2400/240V 60-cycle distribution transformer, the low side volts, amperes, and watts are found to be 240V, 0.75A and 72W. The low side, or secondary is short-circuited when 67V is applied to the high side, rated current of 4.17A flow in the power is 146W. Determine (i) equivalent impedance, referred to high and to low side; (ii) equivalent resistances; (iii) equivalent leakage reactance at rated load and unity power factor and at 0.80 power factor, lagging current, (iv) efficiency at rated kVA load; (v ) efficiency at 1/8, ½, 4, 5/4 kVA load. Plot efficiency as a function of kVA.

In an open-circuit test of a 10KVA 2400/240V 60-cycle distribution transformer, the low side volts, amperes, and watts are found to be 240V, 0.75A and 72W. The low side, or secondary is short-circuited when 67V is applied to the high side, rated current of 4.17A flow in the power is 146W. Determine (i) equivalent impedance, referred to high and to low side; (ii) equivalent resistances; (iii) equivalent leakage reactance at rated load and unity power factor and at 0.80 power factor, lagging current, (iv) efficiency at rated kVA load; (v ) efficiency at 1/8, ½, 4, 5/4 kVA load. Plot efficiency as a function of kVA.

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 3.16P: A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters:...

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