A Single-phase transformer rated 1000-VA, 240/120 Volts has been tested to determine its equivalent circuit. The results of the tests are: Voltage - Volts Current-Amps Power - Watts Open Circuit Test 120 1.9 82 Short Circuit Test 22 4.2 20.8 a) Find the equivalent circuit of the transformer b) Find the transformer's voltage regulation at rated conditions and (1000 VA and 240 Volts at the high-voltage side terminals): i) 0.8 pf lagging, ii) 1.0 pf and iii) 0.8 pf leading. Determine the percentage of efficiency at 50% of load, pf=0.8 lagging and 240 Volts terminal voltage. c)

A Single-phase transformer rated 1000-VA, 240/120 Volts has been tested to determine its equivalent circuit. The results of the tests are: Voltage - Volts Current-Amps Power - Watts Open Circuit Test 120 1.9 82 Short Circuit Test 22 4.2 20.8 a) Find the equivalent circuit of the transformer b) Find the transformer's voltage regulation at rated conditions and (1000 VA and 240 Volts at the high-voltage side terminals): i) 0.8 pf lagging, ii) 1.0 pf and iii) 0.8 pf leading. Determine the percentage of efficiency at 50% of load, pf=0.8 lagging and 240 Volts terminal voltage. c)

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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