4. 100 kVA, 6800-240 V, 50 Hz single phase step down transformer has the following parameters: RIs=0.0082 Rus=2.62 Rf-HS=5000n XLs=0.0152 Xus=5.22 Xm.Hs=88002 Transformer is delivering 80% of rated load at rated voltage and 0.95 lagging power factor. Determine the following: a) The equivalent impedance of the transformer referred to primary. b) Input impedance of the combined transformer and load. c) Actual input voltage at HV side. d) Input impedance if load is disconnected. e) Exciting current at no load.

4. 100 kVA, 6800-240 V, 50 Hz single phase step down transformer has the following parameters: RIs=0.0082 Rus=2.62 Rf-HS=5000n XLs=0.0152 Xus=5.22 Xm.Hs=88002 Transformer is delivering 80% of rated load at rated voltage and 0.95 lagging power factor. Determine the following: a) The equivalent impedance of the transformer referred to primary. b) Input impedance of the combined transformer and load. c) Actual input voltage at HV side. d) Input impedance if load is disconnected. e) Exciting current at no load.

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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