Q3. Three identical single phase transformer, each rated 1.2kV/120V, 7.2kVA and having a leakage reactance of 0.05 p.u, are connected together to gorm a 3-phase transformer bank. A balanced Y- connected load of 5 ohms per phase is connected across the secondary bank. Determine the Y-equivalent per phase impedance i) in ohms and ii) in p.u seen from the primary side when the transformer bank is connected as a) delta-wye and b) delta – delta

Q3. Three identical single phase transformer, each rated 1.2kV/120V, 7.2kVA and having a leakage reactance of 0.05 p.u, are connected together to gorm a 3-phase transformer bank. A balanced Y- connected load of 5 ohms per phase is connected across the secondary bank. Determine the Y-equivalent per phase impedance i) in ohms and ii) in p.u seen from the primary side when the transformer bank is connected as a) delta-wye and b) delta – delta

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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In per-unit equivalent circuits of practical three-phase transformers, under balanced thr-phase operation, in which of the following connect ions would a phase-shifting transformer come up? (a) Y-Y (b) Y- (c) -
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