The following test results were obtained from a 75 kVA, single-phase transformer with a no-load voltage ratio of 8 kV – 240 V. Open-circuit test results Short-circuit test results Voc = 240V, loc = 7.2 A, Poc = 400 W Vsc = 489.5 V, Isc = 2.5 A, Psc = 240 W (a) Draw a schematic diagram of the transformer, calculate the HV and LV coil ratings (S, V, I) and show these ratings on the schematic diagram. (b) Draw the simplified equivalent circuit of the transformer under open circuit conditions. Calculate the magnetizing impedances referred to the HV side of the transformer. (c) Draw the simplified equivalent circuit of the transformer under short circuit conditions. Calculate the series equivalent impedances referred to the HV side of the transformer.

The following test results were obtained from a 75 kVA, single-phase transformer with a no-load voltage ratio of 8 kV – 240 V. Open-circuit test results Short-circuit test results Voc = 240V, loc = 7.2 A, Poc = 400 W Vsc = 489.5 V, Isc = 2.5 A, Psc = 240 W (a) Draw a schematic diagram of the transformer, calculate the HV and LV coil ratings (S, V, I) and show these ratings on the schematic diagram. (b) Draw the simplified equivalent circuit of the transformer under open circuit conditions. Calculate the magnetizing impedances referred to the HV side of the transformer. (c) Draw the simplified equivalent circuit of the transformer under short circuit conditions. Calculate the series equivalent impedances referred to the HV side of the transformer.

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

Chapter14: Power Distribution

Section: Chapter Questions

Problem 14.8P

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