A 3 phase, star-connected, cylindrical rotor, 10 MVA, 11kV synchronous generator is supplying rated power to a unity power factor load. The terminal voltage and real power input to the machine are kept constant. A purely inductive load is now switched in parallel to the unity power factor load, so that the load draws power at 0.85 power factor lagging. What is the percentage increase in the field excitation current under the new operating condition, if the synchronous rcactance of the machine is 52/ phase? Assume lincar flux- current relationship for the ficld.

A 3 phase, star-connected, cylindrical rotor, 10 MVA, 11kV synchronous generator is supplying rated power to a unity power factor load. The terminal voltage and real power input to the machine are kept constant. A purely inductive load is now switched in parallel to the unity power factor load, so that the load draws power at 0.85 power factor lagging. What is the percentage increase in the field excitation current under the new operating condition, if the synchronous rcactance of the machine is 52/ phase? Assume lincar flux- current relationship for the ficld.

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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