Q1- A single phase transformer consumes 2 A on no load at p.f. 0.208 lagging. The turns ratio is 2/1(step down). If the loads on the secondary is 25 A at a p.f. 0.866 lagging. Find the primary currentand power factor.

Given Data:No-load current (I₀): 2 ANo-load power factor (cosφ₀): 0.208 laggingTurns ratio (N₁/N₂):…

Answered: Q1- A single phase transformer consumes…

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 3.28MCQ

See similar textbooks

Similar questions

An ideal transformer has no real or reactive power loss. (a) True (b) False
A 23/230-kV step-up transformer feeds a three-phase transmission line, which in turn supplies a 150-MVA,0.8 lagging power factor load through a step-down 230/23-kV transformer. The impedance of the line and transformers at 230kVis18+j60. Determine the tap setting for each transformer to maintain the voltage at the load at 23 kV.
Consider an ideal transformer with N1=3000andN2=1000 turns. Let winding 1 be connected to a source whose voltage is e1(t)=100(1| t |)volts for 1t1ande1(t)=0 for | t |1 second. A2- farad capacitor is connected across winding 2. Sketch e1(t),e2(t),i1(t),andi2(t) versus time t.
For a short-circuit test on a 2-winding transformer, with one winding shorted, can you apply the rated voltage on the other winding? (a) Yes (b) No
For an ideal transformer, the efficiency is (a) 0 (b) 100 (c) 50
For an ideal 2-winding transformer, an impedance Z2 connected across winding 2 (secondary) is referred to winding 1 (primary) by multiplying Z2 by (a) The turns ratio (N1/N2) (b) The square of the turns ratio (N1/N2)2 (c) The cubed turns ratio (N1/N2)3
(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 ?
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.
The efficiency of a transformer at load 0.8 p.f. Lag is -- at load 0.8 p.f. Lead * equal less than more than none of these
primary of a certain transformer takes 1 a at a power factor of 0.4 when it is connected acrossa 200-v, 50-hz supply and the secondary is on open circuit. the number of turns on the primary istwice that on the secondary. a load taking 50 a at a lagging power factor of 0.8 is now connectedacross the secondary. what is now the value of primary current ?
In a transformer that has 10 times more turns on the secondary side (side 2) than on the primary side (side 1), the magnitude of the voltage/EMF across the windings on the secondary side, E₂ will be... O a.... 10 times lower than the voltage/emf on the primary side, E₁. O b.... the same as the voltage/emf on the primary side. O c.... always zero regardless of the voltage on the primary side, E₁. O d.... 10 times higher than the voltage/emf on the primary side, E₁.
The full-load efficiency of transformer at 0.85 lagging p.f. is 97%. Its efficiency at full load 0.85 leading power factor will be *

SEE MORE QUESTIONS

Recommended textbooks for you

Power System Analysis and Design (MindTap Course …

Electrical Engineering

ISBN:

9781305632134

Author:

J. Duncan Glover, Thomas Overbye, Mulukutla S. Sarma

Publisher:

Cengage Learning