Q1-A 3-phase step down transformer 1200 KVA , 11000/2200 V, 50 Hz .The resistance /phase and leakage reactance/phase of the primary winding are 1.2Ω and 4.8Ω and the corresponding values for the secondary winding are 0.01Ω and 0.06Ω respectively if the primary winding is connected in delta and secondary in star. calculate: i)The voltage to be applied at normal frequency to the primary to circulate full-load current through it when the secondary is short-circuited ii) The full load copper loss

Q1-A 3-phase step down transformer 1200 KVA , 11000/2200 V, 50 Hz .The resistance /phase and leakage reactance/phase of the primary winding are 1.2Ω and 4.8Ω and the corresponding values for the secondary winding are 0.01Ω and 0.06Ω respectively if the primary winding is connected in delta and secondary in star. calculate: i)The voltage to be applied at normal frequency to the primary to circulate full-load current through it when the secondary is short-circuited ii) The full load copper loss

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 3.9P

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A single-phase, 50-kVA,2400/240-V,60-Hz distribution transformer has the following parameters: Resistance of the 2400-V winding: R1=0.75 Resistance of the 240-V winding: R2=0.0075 Leakage reactance of the 2400-V winding: X1=1.0 Leakage reactance of the 240-V winding: X2=0.01 Exciting admittance on the 240-V side =0.003j0.02S (a) Draw the equivalent circuit referred to the high-voltage side of the transformer. (b) Draw the equivalent circuit referred to the low-voltage side of the transformer. Show the numerical values of impedances on the equivalent circuits.
Consider the three single-phase two-winding transformers shown in Figure 3.37. The high-voltage windings are connected in Y. (a) For the low-voltage side, connect the windings in , place the polarity marks, and label the terminals a, b, and c in accordance with the American standard. (b) Relabel the terminals a, b, and c such that VAN is 90 out of phase with Va for positive sequence.
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