Q18/ A 4-poles, 3-phase, 50 Hz induction motor is running at full-load at 1400 r.p.m. the star- connected rotor has a resistance and standstill reactance of 0.32 per phase respectively. The e.m.f. between slip rings at standstill is 240V. Find for full-load condition (i) e.m.f. induced in each rotor phase (ii) rotor impedance/phase (iii) rotor current and p.f. assuming the slip rings are short circuited. Ans [5.54V , 0.332, 17.84A , 0.97 lag]

Q18/ A 4-poles, 3-phase, 50 Hz induction motor is running at full-load at 1400 r.p.m. the star- connected rotor has a resistance and standstill reactance of 0.32 per phase respectively. The e.m.f. between slip rings at standstill is 240V. Find for full-load condition (i) e.m.f. induced in each rotor phase (ii) rotor impedance/phase (iii) rotor current and p.f. assuming the slip rings are short circuited. Ans [5.54V , 0.332, 17.84A , 0.97 lag]

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

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