An AC alternator is used to convert mechanical power to electrical power. Energy in mechanical form originating from motor, turbine rotation and others are converted to electrical power via alternators. a. Describe the operation of an alternator in detail. b. Explain in detail the zero-power factor method? c. A 5000 kVA, high voltage, 3 phase, star connected alternator has a resistance of 0.75 Q per phase. Estimate by the zero-power factor method, the regulation for a load of 400A at power factor (i) unity (ii) 0.93 leading, (ii) 0.75 lagging From the following open circuit and full load, zero power factor curves: Open circuit terminal voltage, V 3100 4900 Field Current, A Saturation curve zero power factor, V 32 50 1850 75 4250 100 140 6600 7500 8300 5800 7000

An AC alternator is used to convert mechanical power to electrical power. Energy in mechanical form originating from motor, turbine rotation and others are converted to electrical power via alternators. a. Describe the operation of an alternator in detail. b. Explain in detail the zero-power factor method? c. A 5000 kVA, high voltage, 3 phase, star connected alternator has a resistance of 0.75 Q per phase. Estimate by the zero-power factor method, the regulation for a load of 400A at power factor (i) unity (ii) 0.93 leading, (ii) 0.75 lagging From the following open circuit and full load, zero power factor curves: Open circuit terminal voltage, V 3100 4900 Field Current, A Saturation curve zero power factor, V 32 50 1850 75 4250 100 140 6600 7500 8300 5800 7000

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 3.38P: Consider a three-phase generator rated 300MVA,23kV, supplying a system load of 240 MA and 0.9 power...

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