A 30 hp, three-phase, wye connected, 60 Hz, 360 VLL, synchronous motor is operating at 50% full load, rated voltage and 0.8 pf leading (over-excited). The motor has negligible armature resistance and a synchronous reactance of 2.5 2/phase. Stator core loss is 1kW and friction and windage loss is 1.5 kW. a. Draw a phasor diagram to illustrate the leading power factor operating condition. Show symbols only b. Calculate the motor line-to-neutral excitation voltage and load angle when it is operating at 50% full load, rated voltage and 0.8 pf leading (over-excited). C. Draw a phasor diagram to illustrate the lagging power factor operating condition. Show symbols only

A 30 hp, three-phase, wye connected, 60 Hz, 360 VLL, synchronous motor is operating at 50% full load, rated voltage and 0.8 pf leading (over-excited). The motor has negligible armature resistance and a synchronous reactance of 2.5 2/phase. Stator core loss is 1kW and friction and windage loss is 1.5 kW. a. Draw a phasor diagram to illustrate the leading power factor operating condition. Show symbols only b. Calculate the motor line-to-neutral excitation voltage and load angle when it is operating at 50% full load, rated voltage and 0.8 pf leading (over-excited). C. Draw a phasor diagram to illustrate the lagging power factor operating condition. Show symbols only

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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