(b) A 100 kVA, 2300:230 V, 50 Hz, single-phase transformer has the following parameters: Resistance of the primary (high-voltage) winding: Resistance of the secondary (low-voltage) winding: Leakage reactance of the primary (high-voltage) winding: Leakage reactance of the secondary (low-voltage) winding: Core loss resistance (referred to the primary): Magnetising reactance (referred to the primary): R₁ = 0.25 Ω R₂ = 0.0025 2 X₁ = 0.52 X2 = 0.0052 Ω Rc = 10 k = 2.2 ΚΩ Xm The transformer is delivering full (rated) load at a rated secondary voltage of 230 V and 0.82 power factor lagging. (i) Draw the cantilever equivalent circuit of the transformer (including component values) referred to the primary (high-voltage) side and in which the shunt branch has been moved to the secondary. (ii) Calculate the phasor load current Ĭ2, referred to the primary. (iii) If the transformer is being used as a step-down transformer at the load end of a feeder with impedance Zƒ = (0.4 + j) ₁, calculate the magnitude of the voltage at the sending end of the feeder (Hint: You may ignore the exciting current, and drawing an appropriate phasor diagram may assist your answer.)

(b) A 100 kVA, 2300:230 V, 50 Hz, single-phase transformer has the following parameters: Resistance of the primary (high-voltage) winding: Resistance of the secondary (low-voltage) winding: Leakage reactance of the primary (high-voltage) winding: Leakage reactance of the secondary (low-voltage) winding: Core loss resistance (referred to the primary): Magnetising reactance (referred to the primary): R₁ = 0.25 Ω R₂ = 0.0025 2 X₁ = 0.52 X2 = 0.0052 Ω Rc = 10 k = 2.2 ΚΩ Xm The transformer is delivering full (rated) load at a rated secondary voltage of 230 V and 0.82 power factor lagging. (i) Draw the cantilever equivalent circuit of the transformer (including component values) referred to the primary (high-voltage) side and in which the shunt branch has been moved to the secondary. (ii) Calculate the phasor load current Ĭ2, referred to the primary. (iii) If the transformer is being used as a step-down transformer at the load end of a feeder with impedance Zƒ = (0.4 + j) ₁, calculate the magnitude of the voltage at the sending end of the feeder (Hint: You may ignore the exciting current, and drawing an appropriate phasor diagram may assist your answer.)

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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Similar questions

For a short-circuit test on a 2-winding transformer, with one winding shorted, can you apply the rated voltage on the other winding? (a) Yes (b) No
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