A single-phase step-down transformer of 83 kVA, nominal voltages 24kV/230 V, frequency 60 Hz is available.The following test parameters are available:Pfe = 216W, Io = 2%, Pcc = 1083W, Vcc = 4% Determine: If the transformer is connected to 24 kV, a load Zc, fp = 0.866 in arrears, is installed in the secondary transformer, which consumes the nominal current. Calculate:• Transformer voltage regulation (perform calculations by PU's)• Maximum efficiency.

A single-phase step-down transformer of 83 kVA, nominal voltages 24kV/230 V, frequency 60 Hz is available.The following test parameters are available:Pfe = 216W, Io = 2%, Pcc = 1083W, Vcc = 4% Determine: If the transformer is connected to 24 kV, a load Zc, fp = 0.866 in arrears, is installed in the secondary transformer, which consumes the nominal current. Calculate:• Transformer voltage regulation (perform calculations by PU's)• Maximum 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 3.11MCQ: For a short-circuit test on a 2-winding transformer, with one winding shorted, can you apply the...

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A single-phase step-down transformer is rated 13MVA,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. Determine Req1andXeq1 in ohms referred to the high-voltage winding.
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