Two phases and the neutral of a 22-kV three-phase distributionline serve a remote rural road. A farmer along the road has a 455-V feeder supplying 225 kW at 0.4 PF lagging of three-phase loads,plus a total of 55 kW at 0.9 PF lagging of single-phase loads. Thesingle-phase loads are distributed evenly among the three phases.For economic reasons, the utility used two single phase transform-ers, X and Y, in an open Y (primary) and open delta (secondary)to feed the farm, as in the figure. Find the voltages and currentsin each of the four coils of the two transformers. Also find theactive and reactive powers supplied by each transformer. Assumethe transformers are ideal.A Yd5 open wye/open delta, feeding two three phase loads.x1Yd5(a) V₁1(e) L1(i) P, :— kW (j) Q :kVAr-A (f)— kV (b) V2V (c) Vy1kV (d) V₁2:Vy₁kV _Vx2L₂:MA (g) Iy: A (h) Iy2: _A_kVAr (k) Py:kW (1) Qy:

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Answered: 22-kV three-phase distribution

Engineering

Electrical Engineering

22-kV three-phase distribution

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 3.43P: Three single-phase transformers, each rated 10MVA,66.4/12.5kV,60Hz, with an equivalent series...

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