1: A conductor moves with a velocity of 22 ms-1 at an angle of 500 to a magnetic field of length 5 cm. If the magnitude of the induced emf is 105 V, determine the flux leaving the pole face. 2: A 400 kVA, 4000 V/200 V, 50 Hz single-phase transformer has 80 primary turns. Calculate (a) the primary and the secondary currents, (b) the number of secondary turns, and (c) the value of the mutual flux. 3: A 100 KVA transformer has primary and secondary winding resistances of 0.7 0 and 0.0280 respectively. The primary and secondary voltages are 1200 V and 840 V respectively. If the power factor of the load is 0.85, determine the core loss if the efficiency of the transformer is 89%. Draw the power diagram for the transformer.

1: A conductor moves with a velocity of 22 ms-1 at an angle of 500 to a magnetic field of length 5 cm. If the magnitude of the induced emf is 105 V, determine the flux leaving the pole face. 2: A 400 kVA, 4000 V/200 V, 50 Hz single-phase transformer has 80 primary turns. Calculate (a) the primary and the secondary currents, (b) the number of secondary turns, and (c) the value of the mutual flux. 3: A 100 KVA transformer has primary and secondary winding resistances of 0.7 0 and 0.0280 respectively. The primary and secondary voltages are 1200 V and 840 V respectively. If the power factor of the load is 0.85, determine the core loss if the efficiency of the transformer is 89%. Draw the power diagram for the transformer.

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...

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