The rotational losses for a 1000 hp synchronous motor are found to be 18 kW. The motor operates from a 2300 V three-phase supply. The machine's synchronous reactance is 1.9 2 and that the armature resistance is negligible. Establish the following points (11l and E) on the V curve corresponding to full-load power output: 1. Stability limit, 8 = -90°. 2. Power factor of 0.8 lagging. 3. Unity power factor. 4. Power factor of 0.8 leading.

The rotational losses for a 1000 hp synchronous motor are found to be 18 kW. The motor operates from a 2300 V three-phase supply. The machine's synchronous reactance is 1.9 2 and that the armature resistance is negligible. Establish the following points (11l and E) on the V curve corresponding to full-load power output: 1. Stability limit, 8 = -90°. 2. Power factor of 0.8 lagging. 3. Unity power factor. 4. Power factor of 0.8 leading.

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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