The secondary winding of a transformer has a terminal voltage of Vsec (t) = 234 sin (377t) V. The turns ratio of the transformer (N1/N2) is 72:201. If the secondary current of the transformer isec (t) = 12 sin(377t + [25°]), (a) What is the RMS value of the primary current of this transformer? (b) What are its voltage reg- ulation and (c) efficiency? The impedances of this transformer referred to the primary side are Rsc = 0.292, Xsc=0.752 and Re=30092, Xm= 7092. N.B. To compute the regulation, neglect the excitation current of the transformer, io = ic+im. Single phase transformer with a load. R₂ JX wwm (~) v, (1) N₁ N₂ Hi jX R₂ (a) RMS of primary current: A (b) Voltage regulation: % (c) Efficiency: -%

The secondary winding of a transformer has a terminal voltage of Vsec (t) = 234 sin (377t) V. The turns ratio of the transformer (N1/N2) is 72:201. If the secondary current of the transformer isec (t) = 12 sin(377t + [25°]), (a) What is the RMS value of the primary current of this transformer? (b) What are its voltage reg- ulation and (c) efficiency? The impedances of this transformer referred to the primary side are Rsc = 0.292, Xsc=0.752 and Re=30092, Xm= 7092. N.B. To compute the regulation, neglect the excitation current of the transformer, io = ic+im. Single phase transformer with a load. R₂ JX wwm (~) v, (1) N₁ N₂ Hi jX R₂ (a) RMS of primary current: A (b) Voltage regulation: % (c) Efficiency: -%

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 3.17P: The transformer of Problem 3.16 is supplying a rated load of 50 kVA at a rated secondary voltage of...

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