4. A 6.6 kV, 3-phase, star-connected turbo-alternator of synchronous reactance 0.5 ohm/phase is ap-plying 40 MVA at 0.8 lagging p.f. to a large system. If the steam supply is suddenly cut off, explainwhat takes place and determine the current the machine will then cary. Neglect losses.12100 A] (Elect. Machines (E-3) AMIE Sec. B Summer 1990)5. A3-phase 400 kVA, 6.6 kV, 1500 rpm., 50 Hz alternator is running in parallel with infinite bus bars.Its synchronous reactance is 25%. Calculate (f) for no load (i) full load 0.8 p.f. lagging the synchro-nizing power and torque per unit mechanical angle of displacement.[Rajive Gandhi Technical University, 2000) () 55.82 kW, 355 Nw-m () 64.2 kW, 409 Nw-m]

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A 6.6 kV, 3-phase, star-connected turbo-alternator of synchronous reactance 0.5 ohm/phase is ap- plying 40 MVA at 0.8 lagging p.f. to a large system. If the steam supply is suddenly cut off, explain what takes place and determine the current the machine will then carry. Neglect losses. 12100 A] (Elect. Machines (E-3) AMIE Sec. B Summer 1990)

A 6.6 kV, 3-phase, star-connected turbo-alternator of synchronous reactance 0.5 ohm/phase is ap- plying 40 MVA at 0.8 lagging p.f. to a large system. If the steam supply is suddenly cut off, explain what takes place and determine the current the machine will then carry. Neglect losses. 12100 A] (Elect. Machines (E-3) AMIE Sec. B Summer 1990)

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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