A 1500KVA, 11KV, 50Hz, Star connected synchronous generator is tested by operating it as a synchronous motor on no-load. The results are as follows: When operated as a synchronous motor on load the power input to the motor is 55.8KW and the armature line current is 70A. The excitation of 38.6A at 250V dc gives the normal open-circuit voltage. DC resistance test: dc line voltage 17.5V and dc line current 70A. Take the effective resistance as 1.6 times the dc resistance. Calculate the efficiency of the machine on 80% of the full-load and 0.75 power factor lagging

A 1500KVA, 11KV, 50Hz, Star connected synchronous generator is tested by operating it as a synchronous motor on no-load. The results are as follows: When operated as a synchronous motor on load the power input to the motor is 55.8KW and the armature line current is 70A. The excitation of 38.6A at 250V dc gives the normal open-circuit voltage. DC resistance test: dc line voltage 17.5V and dc line current 70A. Take the effective resistance as 1.6 times the dc resistance. Calculate the efficiency of the machine on 80% of the full-load and 0.75 power factor lagging

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

Chapter11: Transient Stability

Section: Chapter Questions

Problem 11.1P

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