3kVA, 230/115V transformer is tested with the following results: Open circuit test: Vac = 230V ; Ica = 1.6A ; Pca = 50W Short circuit test: Vcc = 4.5V ; Icc =13.04A; Pcc = 50W Find Rep (Equivalent resistance referred to the primary winding), Xep(Equivalent reactance referred to the primary winding), Res (Equivalent resistance referred to the secondary winding), Xes (Equivalent reactance referred to the secondary winding) and the efficiency when feeding a 2kVA load with a power factor of 0.85 lagging. ..

3kVA, 230/115V transformer is tested with the following results: Open circuit test: Vac = 230V ; Ica = 1.6A ; Pca = 50W Short circuit test: Vcc = 4.5V ; Icc =13.04A; Pcc = 50W Find Rep (Equivalent resistance referred to the primary winding), Xep(Equivalent reactance referred to the primary winding), Res (Equivalent resistance referred to the secondary winding), Xes (Equivalent reactance referred to the secondary winding) and the efficiency when feeding a 2kVA load with a power factor of 0.85 lagging. ..

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 3.57P: A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when...

See similar textbooks

Similar questions

A two-winding single-phase transformer rated 60kVA,240/1200V,60Hz, has an efficiency of 0.96 when operated at rated load, 0.8 power factor lagging. This transformer is to be utilized as a 1440/1200-V step-down autotransformer in a power distribution system. (a) Find the permissible kVA rating of the autotransformer if the winding currents and voltages are not to exceed the ratings as a two-winding transformer. Assume an ideal transformer. (b) Determine the efficiency of the autotransformer with the kVA loading of part (a) and 0.8 power factor leading.
An infinite bus, which is a constant voltage source, is connected to the primary of the three-winding transformer of Problem 3.53. A 7.5-MVA,13.2-kV synchronous motor with a sub transient reactance of 0.2 per unit is connected to the transformer secondary. A5-MW,2.3-kV three-phase resistive load is connected to the tertiary Choosing a base of 66 kV and 15 MVA in the primary, draw the impedance diagram of the system showing per-unit impedances. Neglect transformer exciting current, phase shifts, and all resistances except the resistive load.
(a) An ideal single-phase two-winding transformer with turns ratio at=N1/N2 is connected with a series impedance Z2 across winding 2. If one wants to replace Z2, with a series impedance Z1 across winding 1 and keep the terminal behavior of the two circuits to be identical, find Z1 in terms of Z2. (b) Would the above result be true if instead of a series impedance there is a shunt impedance? (c) Can one refer a ladder network on the secondary (2) side to the primary (1) side simply by multiplying every impedance byat2 ?
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.
A short-circuit test was performed on a 10kVA, 2000/400 V single phase transformer. The instruments indicated 100V, 5A and 100 W. Determine the secondary voltage when operating at rated load at 80% pf lagging at rated primary voltage. Provide values in order the space provided below: Re, Xe, I1, I2, and E1, E2
Primary side-reduced equivalent circuit parameters of a 25 KVA, 50 Hz, 4000/400 Volt transformer R1 = 32 Ω, X1 = 45 Ω, Rc = 250000 Ω, R2 '= 66.14 Ω, X2' = 79.34 Ω, Xm It is given as = 30000 Ω. Since the secondary of the transformer is fed at a full load rated voltage with an advanced power factor of 0.9, for these operating conditions; a) Calculate the primary voltage using the T equivalent circuit. (Only the amplitude of the voltage and the phase value will not be entered.) b) Calculate the efficiency of the transformer. c )Calculate the voltage regulation of the transformer.
A 1000-VA, 230/115-V traformer has been tested to determine its equivalent circuit. The results are shown below: Open-Circuit Test results from the low voltage side: VOC = 115 V, IOC = 0.1 A, POC = 5 W; Short-Circuit Test results from the high voltage side: VSC = 20 V, ISC = 10 A, PSC = 50 W; Find the transformer’s voltage regulation, in percent, at 50% loading conditions and 0.8 PF lagging. Note: (If %1, the you should write as '1', not as '0,01')
1.The equivalent parameters of a 150kVA, 2400V/240V transformer, are R1=0.2Ω, R2=2mΩ, X1=0.45Ω, X2=4.5mΩ, Rc=10kΩ, and Xm=1.55kΩ. The transformer is operating at rated load and rated voltage with 0.8 lagging power factor. Using the approximate equivalent circuit referred to the primary side, determine: (i) (i) the voltage regulation (ii) (ii) the transformer power loss and efficiency 2.Nanoscale drives occur in the living world for example in the bacterial flagellum or ATP synthase. For one of these drives describe with the aid of diagrams how it operates and discuss the features which the drive has in common with large scale, man-made counterparts. 3.A 15 kW, 250V shunt motor with Ra=0.22 Ω, Rf=170 Ω. At no-load and rated voltage, the speed is 1200 rpm and the armature current is 3 A. At full-load and rated voltage, the line current is 55A. What is the full-load speed?
The equivalent parameters of a 150kVA, 2400V/240V transformer, are R1=0.2Ω, R2=2mΩ, X1=0.45Ω, X2=4.5mΩ, Rc=10kΩ, and Xm=1.55kΩ. The transformer is operating at rated load and rated voltage with 0.8 lagging power factor. Using the approximate equivalent circuit referred to the primary side, determine: (i) the voltage regulation (ii) the transformer power loss and efficiency Please refer to the answer
Q3:(a) A 500/100 V potential transformer has the following constants: Primary winding resistance =40.25Ω ,Secondary winding resistance =0.45Ω, Primary winding reactance =32.12Ω.Secondary winding reactance is negligible; no load primary current= 0.1A at 0.5 p.f. Calculate : No load angle between primary winding and reversed secondary winding voltages, The value of secondary winding current at unity p.f. when the phase angle is zero.
3) The results of an open circuit test and a short circuit test In a 450 kVA transformer, 42000/2400 V, 60 Hz are the following: Open circuit test (low voltage side) VCA = 2400 V ICA = 18,1 A PCA = 3785 in Short circuit test (High voltage side) Vcc = 1910 V Icc = 11,9 A PCC3850 W a) Find the equivalent circuit of the transformer referred to the bass side voltage. b) Calculate the efficiency of the transformer at full load with a factor of Power of 0.85 in delay.
2) A 20 KVA, 2400/240 V, 60 Hz transformer, to Determine the equivalent circuit impedances. The data obtained from The open circuit and short circuit tests carried out on the primary side of the transformer are the following: Open circuit test VCA = 2400 V ICA = 0.20 A PCA = 50 W Short circuit test Vcc = 50 V Icc = 8.33 A PCC = 230 W a) Determine the equivalent circuit parameters of the transformer referred to the high voltage side. b) Find the transformer voltage regulation for conditions Nominal and F.P. 0.9 in delay.