(a) A 450V, 50 Hz, Y-connected, six poles synchronous generator has a per-phase synchronous reactance of 2.002. Its full-load armature current is 55A at 0.7 PF lagging. This generator has friction and windage losses of 1.8kW and core losses of 1.5kW at 60 Hz at full load. Since the armature resistance is being ignored, assume that 12R losses are neglible. The field current has been adjusted so that the terminal voltage is 450V at no load. Determine the speed of rotation of this generator. Calculate the efficiency of this generator (ignoring the unknown electrically losses) when it is operating at the rated current and 0.8 PF lagging. Assume that the phase voltage at the rated load and 0.8PF lagging is 236.8V. Analyze the shaft torque required by the prime mover at full load. (iii) (iv) Determine the induced countertorque required by the system.

(a) A 450V, 50 Hz, Y-connected, six poles synchronous generator has a per-phase synchronous reactance of 2.002. Its full-load armature current is 55A at 0.7 PF lagging. This generator has friction and windage losses of 1.8kW and core losses of 1.5kW at 60 Hz at full load. Since the armature resistance is being ignored, assume that 12R losses are neglible. The field current has been adjusted so that the terminal voltage is 450V at no load. Determine the speed of rotation of this generator. Calculate the efficiency of this generator (ignoring the unknown electrically losses) when it is operating at the rated current and 0.8 PF lagging. Assume that the phase voltage at the rated load and 0.8PF lagging is 236.8V. Analyze the shaft torque required by the prime mover at full load. (iii) (iv) Determine the induced countertorque required by the system.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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