Three zones of a single-phase circuit are identified in the figure. The zones are connected by transformers T₁ and T2, whose ratings are also shown. Using base values of 100 kVA and 240 volts in zone 1, draw the per-unit circuit and determine the per-unit impedances and the per-unit source voltage. Then calculate the load current both in per-unit and in amperes. Transformer winding resistances and shunt admittance branches are neglected. Zone 1 Zone 2 T T2₂ 20 KVA 460/115 volts Vs = 220/0° volts 3---38 T, 30 KVA 240/480 volts = 0.10 p.u. Xoa Xune = 2 fl Xeg Zone 3 ww Zload = 0.9 - 10.20 = 0.10 p.u.

Three zones of a single-phase circuit are identified in the figure. The zones are connected by transformers T₁ and T2, whose ratings are also shown. Using base values of 100 kVA and 240 volts in zone 1, draw the per-unit circuit and determine the per-unit impedances and the per-unit source voltage. Then calculate the load current both in per-unit and in amperes. Transformer winding resistances and shunt admittance branches are neglected. Zone 1 Zone 2 T T2₂ 20 KVA 460/115 volts Vs = 220/0° volts 3---38 T, 30 KVA 240/480 volts = 0.10 p.u. Xoa Xune = 2 fl Xeg Zone 3 ww Zload = 0.9 - 10.20 = 0.10 p.u.

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 3.26P: A bank of three single-phase transformers, each rated 30MVA,38.1/3.81kV, are connected in Y- with a...

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