The single-phase step-down transformer is rated 13 MVA, 66kV/11.5kV. With the 11.5 kV winding short-circuited, rated current flows when the voltage applied to the primary is 5.5 kV. The power input is read as 100 kW. (a) Determine Reg and Xeg in N referred to the secondary side. (b) Neglect the magnitizing branch. If a load of 10 MW at 0.8 power factor lagging is connected to the secondary side at the rated voltage, compute the transformer efficiency.

The single-phase step-down transformer is rated 13 MVA, 66kV/11.5kV. With the 11.5 kV winding short-circuited, rated current flows when the voltage applied to the primary is 5.5 kV. The power input is read as 100 kW. (a) Determine Reg and Xeg in N referred to the secondary side. (b) Neglect the magnitizing branch. If a load of 10 MW at 0.8 power factor lagging is connected to the secondary side at the rated voltage, compute the transformer 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 3.14P: A single-phase 50-kVA,2400/240-volt,60-Hz distribution transformer is used as a step-down...

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