Problem 3 a- A 50-Hz transformer is operated from a 60 Hz supply. Assume that the load does not change. Discuss the corresponding effects on its flux, reactive power requirements, losses, and efficiency. A 50-kVA, 2400/240 V, 60-Hz, single-phase distribution transformer has the following equivalent- circuit parameters referred to the high-voltage side. Xeg = 3.0 2 Reg= 0.5 2 Xm = 4,500 2 Use the equivalent Cantilever model circuit shown in Figure (1). Assume that the load on the secondary of the transformer is 40 kVA at 0.8 p.f. lagging with the receiving end voltage maintained at 240 V. b- Determine the following: i- voltage at the primary side, ii- current at the primary side, iii- active power input at the primary side, iv- reactive power input at the primary side, v- power factor at the primary side, and vi- efficiency of the transformer at this loading. R=30,000 2 Rea Xeg 12 V, Re Xm Figure (1) Equivalent Circuit of Transformer for Problem 3 ll

Problem 3 a- A 50-Hz transformer is operated from a 60 Hz supply. Assume that the load does not change. Discuss the corresponding effects on its flux, reactive power requirements, losses, and efficiency. A 50-kVA, 2400/240 V, 60-Hz, single-phase distribution transformer has the following equivalent- circuit parameters referred to the high-voltage side. Xeg = 3.0 2 Reg= 0.5 2 Xm = 4,500 2 Use the equivalent Cantilever model circuit shown in Figure (1). Assume that the load on the secondary of the transformer is 40 kVA at 0.8 p.f. lagging with the receiving end voltage maintained at 240 V. b- Determine the following: i- voltage at the primary side, ii- current at the primary side, iii- active power input at the primary side, iv- reactive power input at the primary side, v- power factor at the primary side, and vi- efficiency of the transformer at this loading. R=30,000 2 Rea Xeg 12 V, Re Xm Figure (1) Equivalent Circuit of Transformer for Problem 3 ll

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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