A 440 V, 74.6 kW, 50 Hz, 0.8 pf leading, 3-phase, A-connected synchronous motor has an armature resistance of 0.22 Q and a synchronous reactance of 3.0 . Its efficiency at rated conditions is 85%. Evaluate the performance of the motor at rated conditions by determining the following: Motor input power. Motor line current I, and phase current lA. The internal generated voltage EA. Sketch the phasor diagram. If the motor's flux is increased by 20%, calculate the new values of EA and IA, and the motor power factor. Sketch the new phasor diagram on the same diagram as in 1.1.3 (use dotted lines).

A 440 V, 74.6 kW, 50 Hz, 0.8 pf leading, 3-phase, A-connected synchronous motor has an armature resistance of 0.22 Q and a synchronous reactance of 3.0 . Its efficiency at rated conditions is 85%. Evaluate the performance of the motor at rated conditions by determining the following: Motor input power. Motor line current I, and phase current lA. The internal generated voltage EA. Sketch the phasor diagram. If the motor's flux is increased by 20%, calculate the new values of EA and IA, and the motor power factor. Sketch the new phasor diagram on the same diagram as in 1.1.3 (use dotted lines).

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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