(b) A single-phase transformer, with primary turns of 500, is delivering full-load of 80 kW at a lagging power factor of 0.8 from a 220 V, 50 Hz supply. The current delivered to the load is 227 A. i. Estimate the peak magnetizing flux, Pmaz in the transformer. ii. What is the turns ratio of the transformer? ii. Determine the load impedance. iv. Determine the current drawn from the supply. v. Assume the core and copper losses are 800 W and 3200 W respectively. Detemine the input power and efficiency of the transformer. vi. If the load impedance on the transformer is doubled, what will be effect on the core and copper losses? What is the efficiency at this operating condition?

(b) A single-phase transformer, with primary turns of 500, is delivering full-load of 80 kW at a lagging power factor of 0.8 from a 220 V, 50 Hz supply. The current delivered to the load is 227 A. i. Estimate the peak magnetizing flux, Pmaz in the transformer. ii. What is the turns ratio of the transformer? ii. Determine the load impedance. iv. Determine the current drawn from the supply. v. Assume the core and copper losses are 800 W and 3200 W respectively. Detemine the input power and efficiency of the transformer. vi. If the load impedance on the transformer is doubled, what will be effect on the core and copper losses? What is the efficiency at this operating condition?

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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