480V, 375 kVA, 0.8 lagging power factor Y - connected synchronous generator has synchronous reactance of 0.4 ohm and negligible armature resistance. This generator is supplying power to 480V 80KW 0.8 P.F leading , Y - connected S.M with synchronous reactance of 1.1 ohm and negligible armature resistance . The S.G is adjusted to have a terminal voltage of 480V when the motor is drawing the rated power at unity power factor . Calculate 1) the magnitudes and angles of emf for both machines. 2) if the flux of motors is increased by 10 percent, what happens to the terminal voltage of power system? What is its new value ? 3) what is the power factor of the motor at the new case.

480V, 375 kVA, 0.8 lagging power factor Y - connected synchronous generator has synchronous reactance of 0.4 ohm and negligible armature resistance. This generator is supplying power to 480V 80KW 0.8 P.F leading , Y - connected S.M with synchronous reactance of 1.1 ohm and negligible armature resistance . The S.G is adjusted to have a terminal voltage of 480V when the motor is drawing the rated power at unity power factor . Calculate 1) the magnitudes and angles of emf for both machines. 2) if the flux of motors is increased by 10 percent, what happens to the terminal voltage of power system? What is its new value ? 3) what is the power factor of the motor at the new case.

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 11.19P

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