Three 2.5 kVA single phase 415 V / 1000 V, 50 Hz transformer are connected in Delta-Star con- figuration to form a three-phase transformer bank. Each transformer has the following equivalent circuit parameters referred to the primary: Req=0.7 N, Xeq = 0.8 , Ro= 4200 , Xo = 5350 N The transformer secondary line current is measured to be 2 A when a star connected load with a lagging power factor of 0.8 is connected. The transformer primary is supplied at its rated voltage. Calculate the total copper losses in the transformer under this operating condition: (a) 48.77 W (b) 59.6 W (c) 67.1 W (d) 26.4 W (e) 70.4 W

Three 2.5 kVA single phase 415 V / 1000 V, 50 Hz transformer are connected in Delta-Star con- figuration to form a three-phase transformer bank. Each transformer has the following equivalent circuit parameters referred to the primary: Req=0.7 N, Xeq = 0.8 , Ro= 4200 , Xo = 5350 N The transformer secondary line current is measured to be 2 A when a star connected load with a lagging power factor of 0.8 is connected. The transformer primary is supplied at its rated voltage. Calculate the total copper losses in the transformer under this operating condition: (a) 48.77 W (b) 59.6 W (c) 67.1 W (d) 26.4 W (e) 70.4 W

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 3.9P

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