Question-7 A 3 0, eight-pole, 50 Hz, 6600 V, star-connected synchronous motor has a synchronous impedance of 0.66 + j6.6 O per phase. When excited to give a generated e.m.f. of 4500 V per phase, it takes an input of 2500 kW. a. Calculate the electromagnetic torque, the input current, power factor and load angle If the motor were to be operating at an input current of 180 A at unity power-factor, b. What would then be the value of (EA)? Under these conditions. c. Calculate also the mechanical output and efficiency if mechanical, excitation and iron losses total 50 kW.

Question-7 A 3 0, eight-pole, 50 Hz, 6600 V, star-connected synchronous motor has a synchronous impedance of 0.66 + j6.6 O per phase. When excited to give a generated e.m.f. of 4500 V per phase, it takes an input of 2500 kW. a. Calculate the electromagnetic torque, the input current, power factor and load angle If the motor were to be operating at an input current of 180 A at unity power-factor, b. What would then be the value of (EA)? Under these conditions. c. Calculate also the mechanical output and efficiency if mechanical, excitation and iron losses total 50 kW.

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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