1. A 10 kVA, single-phase, 2400-V:120-V, 60 Hz transformer has an equivalent impedance referred to LV side of 0.01 + j0.09 Q. This transformer has a core loss of 100 W at rated voltage. When rated current is applied to the 2400-V winding, the exciting current in that winding is found to be 0.2 A. a. Find the full-load regulation of this transformer at a power factor of 0.8 lagging. b. Find the efficiency of this transformer at full load, 0.8 power factor lagging. c. If standard open-circuit and tests were performed on this transformer, what would be the measured values of these tests?

1. A 10 kVA, single-phase, 2400-V:120-V, 60 Hz transformer has an equivalent impedance referred to LV side of 0.01 + j0.09 Q. This transformer has a core loss of 100 W at rated voltage. When rated current is applied to the 2400-V winding, the exciting current in that winding is found to be 0.2 A. a. Find the full-load regulation of this transformer at a power factor of 0.8 lagging. b. Find the efficiency of this transformer at full load, 0.8 power factor lagging. c. If standard open-circuit and tests were performed on this transformer, what would be the measured values of these tests?

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 3.9P

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QUESTIONS: 1. A 10 kVA, single-phase, 2400-V:120-V, 60 Hz transformer has an equivalent impedance referred to LV side of 0.01 + j0.09 Q. This transformer has a core loss of 100 W at rated voltage. When rated current is applied to the 2400-V winding, the exciting current in that winding is found to be 0.2 A. a. Find the full-load regulation of this transformer at a power factor of 0.8 lagging. b. Find the efficiency of this transformer at full load, 0.8 power factor lagging. c. Ifstandard open-circuit and tests were performed on this transformer, what would be the measured values of these tests? 2. The following data were obtained on a 2.5 MVA, 50-Hz, 19.1-kV:3.81-kV single-phase transformer tested at 50 Hz: Voltage (V) Current (A) Power (kW) LV winding with HV terminals open-circuited: 3810 9.86 8.14 HV winding with LV terminals short-circuited: 920 141 10.3 a. Calculate the cantilever equivalent-circuit parameters as referred to the transformer high-voltage winding. b. Calculate the…
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A 20 kVA, 2000/200-V, 50-Hz transformer has a high voltage winding resistance of 0.2 and a leakage reactance of 0.240. The low voltage winding resistance is 0.052 and the leakage reactance is 0.02 2. Find the equivalent winding resistance, reactance and impedance referred to the (i) high voltage side and (ii) the low-voltage side. (Draw the related equivalent-circuits) @