1. Let a 5-kVA, 400/200 V transformer be approximately represented by a 2 Q reactance referred to a lowvoltage side. Considering the rated values as base quantities, (a) express the transformer reactance as aper-unit quantity. (b) express the reactance in per-unit quantity for the high voltage side.2. The voltage v(t) = 141.4 cos (@t) is applied to a load consisting of a 10 W resistor in parallel with aninductive X1. = »L = 3.77 W. Calculate the real and reactive power absorbed by the load, and the powerfactor.3. Table list a 4/0 copper conductor with 12 strands. Strand diameter is 0.3373 cm (0.1328 in. ). For thisconductor(a) verify the total copper cross-sectional area of 107.2 mm² (211,600 c.mil) in the table.(b) verify the d.c. resistance at 50° C of 0.1876 W/ km or 0.302 W/ mi. Assume a 2% increase inresistance due to spiraling. (r@20°c = 1.77 x 10* W.m)(c) determine the percent increase in resistance at 60 hz versus d.c. (Reohz, so° c = 0. 1883 W / km)4. a single-phase, 10-kVA, 200-V, generator has an internal impedance Z, of 2 Q. Using the ratings of thegenerator as base values, determine the generated per-unit voltage that is required to produce full-loadcurrent under the short-circuit condition.

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1. Let a 5-kVA, 400/200 V transformer be approximately represented by a 2 Q reactance referred to a low voltage side. Considering the rated values as base quantities, (a) express the transformer reactance as a per-unit quantity. (b) express the reactance in per-unit quantity for the high voltage side.

1. Let a 5-kVA, 400/200 V transformer be approximately represented by a 2 Q reactance referred to a low voltage side. Considering the rated values as base quantities, (a) express the transformer reactance as a per-unit quantity. (b) express the reactance in per-unit quantity for the high voltage side.

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 3.44P: A 130-MVA,13.2-kV three-phase generator, which has a positive-sequence reactance of 1.5 per unit on...

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