3. A single-phase 100-kVA, 7200-V/120-V, 60HZ distribution transformer is used as a step down transformer at the load end of a 7200-V feeder whose series impedance is (2.5 + j3.5) ohms. The equivalent series impedance of the transformer is (0.9 + j2.0) ohms referred to the high voltage (primary) side. The transformer is delivering rated load at 0.8 power factor lagging and at rated secondary voltage. Neglect the transformer exciting current and determine: the voltage at the transformer primary terminals. a. b. the voltage at sending end of the feeder. c. the active and reactive power delivered to the sending end of the feeder.

3. A single-phase 100-kVA, 7200-V/120-V, 60HZ distribution transformer is used as a step down transformer at the load end of a 7200-V feeder whose series impedance is (2.5 + j3.5) ohms. The equivalent series impedance of the transformer is (0.9 + j2.0) ohms referred to the high voltage (primary) side. The transformer is delivering rated load at 0.8 power factor lagging and at rated secondary voltage. Neglect the transformer exciting current and determine: the voltage at the transformer primary terminals. a. b. the voltage at sending end of the feeder. c. the active and reactive power delivered to the sending end of the feeder.

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 3.14P: A single-phase 50-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down...

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