Three zones of a single-phase circuit are identified shown in Figure below. The zones are connected by transformers T1 and T2, whose ratings are also shown. Using base values of 33 kVA and 232 volts in zone 1, Find: 1- Draw the per-unit circuit including the per-unit impedances and the per-unit source voltage. 2- Calculate the load current both in per-unit and in amperes (actual or original value). Zone 1 V₂ = 232.940° Vs "HG T₁ 30 KVA 240/480 volts Хост = 0.10 p.u. Zone 2 Xine = 4 Zload T₂ 20 kVA 460/115 volts Xeg = 0.10 p.u. = Zone 3 +1₁ 1+j2.2 Ω

Three zones of a single-phase circuit are identified shown in Figure below. The zones are connected by transformers T1 and T2, whose ratings are also shown. Using base values of 33 kVA and 232 volts in zone 1, Find: 1- Draw the per-unit circuit including the per-unit impedances and the per-unit source voltage. 2- Calculate the load current both in per-unit and in amperes (actual or original value). Zone 1 V₂ = 232.940° Vs "HG T₁ 30 KVA 240/480 volts Хост = 0.10 p.u. Zone 2 Xine = 4 Zload T₂ 20 kVA 460/115 volts Xeg = 0.10 p.u. = Zone 3 +1₁ 1+j2.2 Ω

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 3.37P: Three single-phase two-winding transformers, each rated 25MVA,54.2/5.42kV, are connected to form a...

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