3.4 A single-phase 100-kVA, 2400/240-volt, 60-Hz distribution transformeris used as a step-down transformer. The load, which is connected to the240-volt secondary winding, absorbs 60 kVA at 0.8 power factor laggingand is at 230 volts. Assuming an ideal transformer, calculate the follow-ing: (a) primary voltage, (b) load impedance, (c) load impedance referredto the primary, and (d) the real and reactive power supplied to the pri-mary winding.3.12 The following data are obtained when open-circuit and short-circuit testsare performed on a single-phase, 50-k VA, 2400/240-volt, 60-Hz distribu-tion transformer.VOLTAGECURRENTPOWER(volts)(amperes)(watts)Measurements on low-voltage sidewith high-voltage winding openMeasurements on high-voltage sidewith low-voltage winding shorted2404.8517352.020.8650(a) Neglecting the series impedance, determine the exciting admittancereferred to the high-voltage side. (b) Neglecting the exciting admittance,determine the equivalent series impedance referred to the high-voltageside. (c) Assuming equal series impedances for the primary and referredsecondary, obtain an equivalent T-circuit referred to the high-voltage side.3.16 A single-phase, 50-kVA, 2400/240-V, 60-Hz distribution transformer hasthe following parameters:Resistance of the 2400-V winding: R, = 0.75 NResistance of the 240-V winding: R, = 0.0075 NLeakage reactance of the 2400-V winding: X, = 1.0 0Leakage reactance of the 240-V winding: X, = 0.01 NExciting admittance on the 240-V side = 0.003 – j0.02 S(a) Draw the equivalent circuit referred to the high-voltage side of thetransformer.(b) Draw the equivalent circuit referred to the low-voltage side of thetransformer. Show the numerical values of impedances on the equiv-alent circuits.

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3.4 A single-phase 100-kVA, 2400/240-volt, 60-Hz distribution transformer is used as a step-down transformer. The load, which is connected to the 240-volt secondary winding, absorbs 60 kVA at 0.8 power factor lagging and is at 230 volts. Assuming an ideal transformer, calculate the follow- ing: (a) primary voltage, (b) load impedance, (c) load impedance referred to the primary, and (d) the real and reactive power supplied to the pri- mary winding.

3.4 A single-phase 100-kVA, 2400/240-volt, 60-Hz distribution transformer is used as a step-down transformer. The load, which is connected to the 240-volt secondary winding, absorbs 60 kVA at 0.8 power factor lagging and is at 230 volts. Assuming an ideal transformer, calculate the follow- ing: (a) primary voltage, (b) load impedance, (c) load impedance referred to the primary, and (d) the real and reactive power supplied to the pri- mary winding.

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 3.4P: A single-phase 100-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down...

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