1. An ideal transformer is shown in Figure 6.12. Use this model for a distribution transformer from VH = 24 kV to Vx = 240 V (RMS). This is, of course, a single phase transformer and is of the type commonly used to provide the 240 V service commonly used in the United States. It is center-tapped to provide 120 V for branch circuits. Assume this transformer is rated at 24 kVA. (a) What are the current ratings Ix and IH? (b) If the secondary ('X') side has 26 turns, how many turns does the primary ('H') side have? (c) If this transformer is loaded by a resistor of value R, what value of R results in the transformer being loaded to its rating? (d) If the secondary is loaded by a resistor of value R, what is the impedance looking into the primary side? 'H ¹x Vx Figure 6.12 Ideal transformer

1. An ideal transformer is shown in Figure 6.12. Use this model for a distribution transformer from VH = 24 kV to Vx = 240 V (RMS). This is, of course, a single phase transformer and is of the type commonly used to provide the 240 V service commonly used in the United States. It is center-tapped to provide 120 V for branch circuits. Assume this transformer is rated at 24 kVA. (a) What are the current ratings Ix and IH? (b) If the secondary ('X') side has 26 turns, how many turns does the primary ('H') side have? (c) If this transformer is loaded by a resistor of value R, what value of R results in the transformer being loaded to its rating? (d) If the secondary is loaded by a resistor of value R, what is the impedance looking into the primary side? 'H ¹x Vx Figure 6.12 Ideal transformer

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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