Exercise 4.4 ▸ A 2.4 KVA, 2400/240 V 50 Hz step down transformer has the following parameters ▸ R₁ = 1.50, X₁ = 2.50, R₂ = 0.0292, X₂ =0.032, 6k, Xml = 8kΩ Rc1 = ▸ It is operating at 80% of its rated load at 0.8 power factor lagging. Using the approximate equivalent circuit of the transformer referred to the secondary side, determine its efficiency (61.4%), the voltage regulation (0.205%) and sketch its phasor diagram.

Exercise 4.4 ▸ A 2.4 KVA, 2400/240 V 50 Hz step down transformer has the following parameters ▸ R₁ = 1.50, X₁ = 2.50, R₂ = 0.0292, X₂ =0.032, 6k, Xml = 8kΩ Rc1 = ▸ It is operating at 80% of its rated load at 0.8 power factor lagging. Using the approximate equivalent circuit of the transformer referred to the secondary side, determine its efficiency (61.4%), the voltage regulation (0.205%) and sketch its phasor diagram.

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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Consider Figure 3.25 of the text for a transformer with off-nominal turns ratio. (i) The per-unit equivalent circuit shown in part (c) contains an ideal transformer which cannot be accommodated by some computer programs. (a) True (b) False (ii) In the - circuit representation for real c in part (d), the admittance parameters Y11 and Y12 would be unequal. (a) True (b) False (iii) For complex c, can the admittance parameters be synthesized with a passive RLC circuit? (a) Yes (b) No
All values of a transformer are proportional to its __________________ ___________________.
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A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when operated at rated load, 0.8 power factor lagging. This transformer is to be utilized as a 1440/1200-V step-down autotransformer in a power distribution system. (a) Find the permissible kVA rating of the autotransformer if the winding currents and voltages are not to exceed the ratings as a two-winding transformer. Assume an ideal transformer. (b) Determine the efficiency of the autotransformer with the kVA loading of part (a) and 0.8 power factor leading.
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