Q1.A 480V, 50HZ,A-connected, 6-pole synchronous generator has a per-phase synchronous reactance of 2 Q Its full-load armature current is 60A at 0.8PF lagging. This generator has friction and windage losses of 1.5kW and core losses of 1 kW at 60HZ at full load. Since the armature resistance is being ignored, assume that the l'R losses are negligible. The field current has been adjusted so that the terminal voltage is 480V at no load. (a) What is the speed of rotation of this generator? (b) What is the terminal voltage of this generator if the following are true? 1. It is loaded with the rated current at 0.8 PF lagging. 2. It is loaded with the rated current at 1.0 PF. 3. It is loaded with the rated current at 0.8 PF leading.

Q1.A 480V, 50HZ,A-connected, 6-pole synchronous generator has a per-phase synchronous reactance of 2 Q Its full-load armature current is 60A at 0.8PF lagging. This generator has friction and windage losses of 1.5kW and core losses of 1 kW at 60HZ at full load. Since the armature resistance is being ignored, assume that the l'R losses are negligible. The field current has been adjusted so that the terminal voltage is 480V at no load. (a) What is the speed of rotation of this generator? (b) What is the terminal voltage of this generator if the following are true? 1. It is loaded with the rated current at 0.8 PF lagging. 2. It is loaded with the rated current at 1.0 PF. 3. It is loaded with the rated current at 0.8 PF 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

Chapter11: Transient Stability

Section: Chapter Questions

Problem 11.3P

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