A three-phase, 13.8 kV, 10 MVA, 0.8 PF-lagging, 60 Hz two-pole, Y-connected steam-turbine generator has a synchronous reactance of 12 Ω per phase and an armature resistance of 1.5 Ω per phase. This generator is operating in parallel with a large power system (infinite bus). a) What is the magnitude of internal voltage Ea at rated conditions ? b) What is power angle δ of the generator at rated conditions ? c) If the field current is constant, what is the maximum active power possible out of this generator (taking into account Ra)? How much reserve power does this generator have at full load ? d) At the absolute maximum active power possible, how much reactive power will this generator be supplying or consuming? Sketch the corresponding phasor diagram assuming If is still unchanged.

A three-phase, 13.8 kV, 10 MVA, 0.8 PF-lagging, 60 Hz two-pole, Y-connected steam-turbine generator has a synchronous reactance of 12 Ω per phase and an armature resistance of 1.5 Ω per phase. This generator is operating in parallel with a large power system (infinite bus). a) What is the magnitude of internal voltage Ea at rated conditions ? b) What is power angle δ of the generator at rated conditions ? c) If the field current is constant, what is the maximum active power possible out of this generator (taking into account Ra)? How much reserve power does this generator have at full load ? d) At the absolute maximum active power possible, how much reactive power will this generator be supplying or consuming? Sketch the corresponding phasor diagram assuming If is still unchanged.

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

Chapter6: Power Flows

Section: Chapter Questions

Problem 6.48P

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