The 240 kV transmission line is intended to be connected to a 220 kV transmission system through an autotransformer. The single-phase transformer that is available to make the connection is 120 MVA and 240kV/20kV Draw the connection of this autotransformer and show on the same diagram: The magnitude of the input and output voltages of the autotransformer (Magnitude and polarity) Currents and in the windings (magnitude and direction) The voltages in the windings (magnitude and polarity) The input and output currents of the autotransformer (magnitude and direction) Calculate the power capacity of this autotransformer

The 240 kV transmission line is intended to be connected to a 220 kV transmission system through an autotransformer. The single-phase transformer that is available to make the connection is 120 MVA and 240kV/20kV Draw the connection of this autotransformer and show on the same diagram: The magnitude of the input and output voltages of the autotransformer (Magnitude and polarity) Currents and in the windings (magnitude and direction) The voltages in the windings (magnitude and polarity) The input and output currents of the autotransformer (magnitude and direction) Calculate the power capacity of this autotransformer

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 3.55P: A single-phase l0-kVA,2300/230-volt,60-Hz two-winding distribution transformer is connected as an...

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The ratings of a three-phase three-winding transformer are Primary(1): Y connected 66kV,15MVA Secondary (2): Y connected, 13.2kV,10MVA Tertiary (3): A connected, 2.3kV,5MVA Neglecting winding resistances and exciting current, the per-unit leakage reactances are X12=0.08 on a 15-MVA,66-kV base X13=0.10 on a 15-MVA,66-kV base X23=0.09 on a 10-MVA,13.2-kV base (a) Determine the per-unit reactances X1,X2,X3 of the equivalent circuit on a 15-MVA,66-kV base at the primary terminals. (b) Purely resistive loads of 7.5 MW at 13.2 kV and 5 MW at 2.3kV are connected to the secondary and tertiary sides of the transformer, respectively. Draw the per- unit impedance diagram, showing the per-unit impedances on a 15-MVA,66-kV base at the primary terminals.
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A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters: Resistance of the 2400-V winding: R1=0.75 Resistance of the 240-V winding: R2=0.0075 Leakage reactance of the 2400-V winding: X1=1.0 Leakage reactance of the 240-V winding: X2=0.01 Exciting admittance on the 240-V side =0.003j0.02S (a) Draw the equivalent circuit referred to the high-voltage side of the transformer. (b) Draw the equivalent circuit referred to the low-voltage side of the transformer. Show the numerical values of impedances on the equivalent circuits.
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