A 120 KVA three -phase transformer (three -phase power), 13200/480 V (line a line) in delta-strella connection has a resistance of 1.3% and a reactance of 8.2% per unit. a) Calculate the phase impedance of the transformer referred to the bass side voltage. b) Calculate the phase impedance of the transformer referred to the high side voltage. c) Calculate the efficiency of the transformer into nominal conditions and with F.P. 0.8 in delay. Three -phase loss in the nucleus is 1500 W.

A 120 KVA three -phase transformer (three -phase power), 13200/480 V (line a line) in delta-strella connection has a resistance of 1.3% and a reactance of 8.2% per unit. a) Calculate the phase impedance of the transformer referred to the bass side voltage. b) Calculate the phase impedance of the transformer referred to the high side voltage. c) Calculate the efficiency of the transformer into nominal conditions and with F.P. 0.8 in delay. Three -phase loss in the nucleus is 1500 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 3.27P: A three-phase transformer is rated 1000MVA,220Y/22kV. The Y-equivalent short-circuit impedance,...

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