Three identical steam-turbine generators G1, G2, and G3 are operating in parallel. Each generator is: 7.2 KV, 21 MVA, 50 Hz, 0.85 PF lagging, 4-poles, Y-connected, with synchronous reactance of 2 Q and an armature resistance of 0.05 Q. Each of generators G1, G2, and G3 has a characteristic power-frequency slope of 5.2 MW/Hz , 4.5 MW/Hz, and 4.9 MW/Hz, respectively The no-load frequency of each generator is set to 52.4 Hz. The load increases with no changes in the settings of the no-load frequencies, until a generator reaches its maximum rated power first. At what system frequency does this limit occur? Select one: O a. fays = 48.97 Hz O b. fsys = 48.25 Hz c. fsys = 49.22 Hz O d. None

Three identical steam-turbine generators G1, G2, and G3 are operating in parallel. Each generator is: 7.2 KV, 21 MVA, 50 Hz, 0.85 PF lagging, 4-poles, Y-connected, with synchronous reactance of 2 Q and an armature resistance of 0.05 Q. Each of generators G1, G2, and G3 has a characteristic power-frequency slope of 5.2 MW/Hz , 4.5 MW/Hz, and 4.9 MW/Hz, respectively The no-load frequency of each generator is set to 52.4 Hz. The load increases with no changes in the settings of the no-load frequencies, until a generator reaches its maximum rated power first. At what system frequency does this limit occur? Select one: O a. fays = 48.97 Hz O b. fsys = 48.25 Hz c. fsys = 49.22 Hz O d. None

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

Chapter7: Symmetrical Faults

Section: Chapter Questions

Problem 7.3MCQ: The amplitude of the sinusoidal symmetrical ac component of the three-phase short-circuit current of...

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